Version 1.1.7

enhanced support for full buffered, non-paged use, for processors with enough RAM

README.md

@@ -67,7 +67,14 @@
 #### other supported panels
 - ED060SCT        6" grey levels, on Waveshare e-Paper IT8951 Driver HAT
 
-### Version 1.1.6
+### Version 1.1.7
+- enhanced support for full buffered, non-paged use, for processors with enough RAM
+- use void display(bool partial_update_mode = false); corresponds to update() in  GxEPD
+- use added void displayWindow(uint16_t x, uint16_t y, uint16_t w, uint16_t h);
+- use added writeImagePart(...), drawImagePart(...), used by displayWindow()
+- added example GxEPD2_NotPagedExample.ino
+- several fixes, e.g. parameter range check in setPartialWindow()
+#### Version 1.1.6
 - added support for GDEH0213B72 2.13" b/w, replacement for GDE0213B1
 - changed SPI speed for IT8951 Driver HAT to 24MHz for write, 10MHz for read
 - minor fixes, e.g. centering of text bounding box in GxEPD2_Example

examples/GxEPD2_Example/GxEPD2_Example.ino

@@ -111,6 +111,7 @@
 //GxEPD2_BW<GxEPD2_290_T5, GxEPD2_290_T5::HEIGHT> display(GxEPD2_290_T5(/*CS=5*/ SS, /*DC=*/ 17, /*RST=*/ 16, /*BUSY=*/ 4)); // GDEW029T5
 //GxEPD2_BW<GxEPD2_270, GxEPD2_270::HEIGHT> display(GxEPD2_270(/*CS=5*/ SS, /*DC=*/ 17, /*RST=*/ 16, /*BUSY=*/ 4));
 //GxEPD2_BW<GxEPD2_420, GxEPD2_420::HEIGHT> display(GxEPD2_420(/*CS=5*/ SS, /*DC=*/ 17, /*RST=*/ 16, /*BUSY=*/ 4));
+//GxEPD2_BW<GxEPD2_583, GxEPD2_583::HEIGHT> display(GxEPD2_583(/*CS=5*/ SS, /*DC=*/ 17, /*RST=*/ 16, /*BUSY=*/ 4));
 //GxEPD2_BW<GxEPD2_750, GxEPD2_750::HEIGHT> display(GxEPD2_750(/*CS=5*/ SS, /*DC=*/ 17, /*RST=*/ 16, /*BUSY=*/ 4));
 // 3-color e-papers
 //GxEPD2_3C<GxEPD2_154c, GxEPD2_154c::HEIGHT> display(GxEPD2_154c(/*CS=5*/ SS, /*DC=*/ 17, /*RST=*/ 16, /*BUSY=*/ 4));
@@ -118,6 +119,7 @@
 //GxEPD2_3C<GxEPD2_290c, GxEPD2_290c::HEIGHT> display(GxEPD2_290c(/*CS=5*/ SS, /*DC=*/ 17, /*RST=*/ 16, /*BUSY=*/ 4));
 //GxEPD2_3C<GxEPD2_270c, GxEPD2_270c::HEIGHT> display(GxEPD2_270c(/*CS=5*/ SS, /*DC=*/ 17, /*RST=*/ 16, /*BUSY=*/ 4));
 //GxEPD2_3C<GxEPD2_420c, GxEPD2_420c::HEIGHT> display(GxEPD2_420c(/*CS=5*/ SS, /*DC=*/ 17, /*RST=*/ 16, /*BUSY=*/ 4));
+//GxEPD2_3C<GxEPD2_583c, GxEPD2_583c::HEIGHT> display(GxEPD2_583c(/*CS=5*/ SS, /*DC=*/ 17, /*RST=*/ 16, /*BUSY=*/ 4));
 //GxEPD2_3C<GxEPD2_750c, GxEPD2_750c::HEIGHT> display(GxEPD2_750c(/*CS=5*/ SS, /*DC=*/ 17, /*RST=*/ 16, /*BUSY=*/ 4));
 // grey levels parallel IF e-papers on Waveshare e-Paper IT8951 Driver HAT
 // HRDY -> 4, RST -> 16, CS -> SS(5), SCK -> SCK(18), MOSI -> MOSI(23), MISO -> MISO(19), GND -> GND, 5V -> 5V
@@ -259,6 +261,8 @@ void setup()
   delay(1000);
   helloEpaper();
   delay(1000);
+  //helloValue(123.9, 1);
+  //delay(1000);
   showFont("FreeMonoBold9pt7b", &FreeMonoBold9pt7b);
   delay(1000);
   drawBitmaps();
@@ -468,6 +472,68 @@ void helloEpaper()
   //Serial.println("helloEpaper done");
 }
 
+#if defined(ESP8266) || defined(ESP32)
+#include <StreamString.h>
+#define PrintString StreamString
+#else
+class PrintString : public Print, public String
+{
+public:
+    size_t write(uint8_t data) override
+    {
+      return concat(char(data));
+    };
+};
+#endif
+
+void helloValue(double v, int digits)
+{
+  //Serial.println("helloValue");
+  display.setRotation(1);
+  display.setFont(&FreeMonoBold9pt7b);
+  display.setTextColor(display.epd2.hasColor ? GxEPD_RED : GxEPD_BLACK);
+  PrintString valueString;
+  valueString.print(v, digits);
+  int16_t tbx, tby; uint16_t tbw, tbh;
+  display.getTextBounds(valueString, 0, 0, &tbx, &tby, &tbw, &tbh);
+  uint16_t x = ((display.width() - tbw) / 2) - tbx;
+  uint16_t y = (display.height() * 3 / 4) + tbh / 2; // y is base line!
+  // show what happens, if we use the bounding box for partial window
+  uint16_t wx = (display.width() - tbw) / 2;
+  uint16_t wy = (display.height() * 3 / 4) - tbh / 2;
+  display.setPartialWindow(wx, wy, tbw, tbh);
+  display.firstPage();
+  do
+  {
+    display.fillScreen(GxEPD_WHITE);
+    display.setCursor(x, y);
+    display.print(valueString);
+  }
+  while (display.nextPage());
+  delay(2000);
+  // make the partial window big enough to cover the previous text
+  uint16_t ww = tbw; // remember window width
+  display.getTextBounds(HelloEpaper, 0, 0, &tbx, &tby, &tbw, &tbh);
+  // adjust, because HelloEpaper was aligned, not centered (could calculate this to be precise)
+  ww = max(ww, uint16_t(tbw + 12)); // 12 seems ok 
+  wx = (display.width() - tbw) / 2;
+  // make the window big enough to cover (overwrite) descenders of previous text
+  uint16_t wh = FreeMonoBold9pt7b.yAdvance;
+  wy = (display.height() * 3 / 4) - wh / 2;
+  display.setPartialWindow(wx, wy, ww, wh);
+  // alternately use the whole width for partial window
+  //display.setPartialWindow(0, wy, display.width(), wh);
+  display.firstPage();
+  do
+  {
+    display.fillScreen(GxEPD_WHITE);
+    display.setCursor(x, y);
+    display.print(valueString);
+  }
+  while (display.nextPage());
+  //Serial.println("helloValue done");
+}
+
 void deepSleepTest()
 {
   //Serial.println("deepSleepTest");

examples/GxEPD2_NotPagedExample/GxEPD2_NotPagedExample.ino

@@ -0,0 +1,1135 @@
+// Display Library example for SPI e-paper panels from Dalian Good Display and boards from Waveshare.
+// Requires HW SPI and Adafruit_GFX. Caution: these e-papers require 3.3V supply AND data lines!
+//
+// Display Library based on Demo Example from Good Display: http://www.e-paper-display.com/download_list/downloadcategoryid=34&isMode=false.html
+//
+// Author: Jean-Marc Zingg
+//
+// Version: see library.properties
+//
+// Library: https://github.com/ZinggJM/GxEPD2
+
+// Supporting Arduino Forum Topics:
+// Waveshare e-paper displays with SPI: http://forum.arduino.cc/index.php?topic=487007.0
+// Good Dispay ePaper for Arduino: https://forum.arduino.cc/index.php?topic=436411.0
+
+// mapping suggestion from Waveshare SPI e-Paper to Wemos D1 mini
+// BUSY -> D2, RST -> D4, DC -> D3, CS -> D8, CLK -> D5, DIN -> D7, GND -> GND, 3.3V -> 3.3V
+
+// mapping suggestion from Waveshare SPI e-Paper to generic ESP8266
+// BUSY -> GPIO4, RST -> GPIO2, DC -> GPIO0, CS -> GPIO15, CLK -> GPIO14, DIN -> GPIO13, GND -> GND, 3.3V -> 3.3V
+
+// mapping of Waveshare e-Paper ESP8266 Driver Board
+// BUSY -> GPIO16, RST -> GPIO5, DC -> GPIO4, CS -> GPIO15, CLK -> GPIO14, DIN -> GPIO13, GND -> GND, 3.3V -> 3.3V
+
+// NOTE for ESP8266: using SS (GPIO15) for CS may cause boot mode problems, use different pin in case
+
+// mapping suggestion for ESP32, e.g. LOLIN32, see .../variants/.../pins_arduino.h for your board
+// NOTE: there are variants with different pins for SPI ! CHECK SPI PINS OF YOUR BOARD
+// BUSY -> 4, RST -> 16, DC -> 17, CS -> SS(5), CLK -> SCK(18), DIN -> MOSI(23), GND -> GND, 3.3V -> 3.3V
+
+// new mapping suggestion for STM32F1, e.g. STM32F103C8T6 "BluePill"
+// BUSY -> A1, RST -> A2, DC -> A3, CS-> A4, CLK -> A5, DIN -> A7
+
+// mapping suggestion for AVR, UNO, NANO etc.
+// BUSY -> 7, RST -> 9, DC -> 8, CS-> 10, CLK -> 13, DIN -> 11
+
+// mapping of Waveshare Universal e-Paper Raw Panel Driver Shield for Arduino / NUCLEO
+// BUSY -> 7, RST -> 8, DC -> 9, CS-> 10, CLK -> 13, DIN -> 11
+
+// mapping suggestion for Arduino MEGA
+// BUSY -> 7, RST -> 9, DC -> 8, CS-> 53, CLK -> 52, DIN -> 51
+
+// base class GxEPD2_GFX can be used to pass references or pointers to the display instance as parameter, uses ~1.2k more code
+// enable or disable GxEPD2_GFX base class
+#define ENABLE_GxEPD2_GFX 0
+
+#include <GxEPD2_BW.h>
+#include <GxEPD2_3C.h>
+#include <Fonts/FreeMonoBold9pt7b.h>
+
+#if defined (ESP8266)
+// select one and adapt to your mapping, can use full buffer size (full HEIGHT)
+//GxEPD2_BW<GxEPD2_154, GxEPD2_154::HEIGHT> display(GxEPD2_154(/*CS=D8*/ SS, /*DC=D3*/ 0, /*RST=D4*/ 2, /*BUSY=D2*/ 4));
+//GxEPD2_BW<GxEPD2_213, GxEPD2_213::HEIGHT> display(GxEPD2_213(/*CS=D8*/ SS, /*DC=D3*/ 0, /*RST=D4*/ 2, /*BUSY=D2*/ 4)); // GDE0213B1, phased out
+//GxEPD2_BW<GxEPD2_213_B72, GxEPD2_213_B72::HEIGHT> display(GxEPD2_213_B72(/*CS=D8*/ SS, /*DC=D3*/ 0, /*RST=D4*/ 2, /*BUSY=D2*/ 4)); // GDEH0213B72
+//GxEPD2_BW<GxEPD2_213_flex, GxEPD2_213_flex::HEIGHT> display(GxEPD2_213_flex(/*CS=D8*/ SS, /*DC=D3*/ 0, /*RST=D4*/ 2, /*BUSY=D2*/ 4)); // GDEW0213I5F
+//GxEPD2_BW<GxEPD2_290, GxEPD2_290::HEIGHT> display(GxEPD2_290(/*CS=D8*/ SS, /*DC=D3*/ 0, /*RST=D4*/ 2, /*BUSY=D2*/ 4));
+//GxEPD2_BW<GxEPD2_290_T5, GxEPD2_290_T5::HEIGHT> display(GxEPD2_290_T5(/*CS=D8*/ SS, /*DC=D3*/ 0, /*RST=D4*/ 2, /*BUSY=D2*/ 4)); // GDEW029T5
+//GxEPD2_BW<GxEPD2_270, GxEPD2_270::HEIGHT> display(GxEPD2_270(/*CS=D8*/ SS, /*DC=D3*/ 0, /*RST=D4*/ 2, /*BUSY=D2*/ 4));
+//GxEPD2_BW<GxEPD2_420, GxEPD2_420::HEIGHT> display(GxEPD2_420(/*CS=D8*/ SS, /*DC=D3*/ 0, /*RST=D4*/ 2, /*BUSY=D2*/ 4));
+// can use only half buffer size
+////GxEPD2_BW < GxEPD2_583, GxEPD2_583::HEIGHT / 2 > display(GxEPD2_583(/*CS=D8*/ SS, /*DC=D3*/ 0, /*RST=D4*/ 2, /*BUSY=D2*/ 4));
+////GxEPD2_BW < GxEPD2_750, GxEPD2_750::HEIGHT / 2 > display(GxEPD2_750(/*CS=D8*/ SS, /*DC=D3*/ 0, /*RST=D4*/ 2, /*BUSY=D2*/ 4));
+// 3-color e-papers
+//GxEPD2_3C<GxEPD2_154c, GxEPD2_154c::HEIGHT> display(GxEPD2_154c(/*CS=D8*/ SS, /*DC=D3*/ 0, /*RST=D4*/ 2, /*BUSY=D2*/ 4));
+//GxEPD2_3C<GxEPD2_213c, GxEPD2_213c::HEIGHT> display(GxEPD2_213c(/*CS=D8*/ SS, /*DC=D3*/ 0, /*RST=D4*/ 2, /*BUSY=D2*/ 4));
+//GxEPD2_3C<GxEPD2_290c, GxEPD2_290c::HEIGHT> display(GxEPD2_290c(/*CS=D8*/ SS, /*DC=D3*/ 0, /*RST=D4*/ 2, /*BUSY=D2*/ 4));
+//GxEPD2_3C<GxEPD2_270c, GxEPD2_270c::HEIGHT> display(GxEPD2_270c(/*CS=D8*/ SS, /*DC=D3*/ 0, /*RST=D4*/ 2, /*BUSY=D2*/ 4));
+// can use only half buffer size
+////GxEPD2_3C<GxEPD2_420c, GxEPD2_420c::HEIGHT / 2> display(GxEPD2_420c(/*CS=D8*/ SS, /*DC=D3*/ 0, /*RST=D4*/ 2, /*BUSY=D2*/ 4));
+// can use only quarter buffer size
+////GxEPD2_3C < GxEPD2_583c, GxEPD2_583c::HEIGHT / 4 > display(GxEPD2_583c(/*CS=D8*/ SS, /*DC=D3*/ 0, /*RST=D4*/ 2, /*BUSY=D2*/ 4));
+////GxEPD2_3C<GxEPD2_750c, GxEPD2_750c::HEIGHT / 4> display(GxEPD2_750c(/*CS=D8*/ SS, /*DC=D3*/ 0, /*RST=D4*/ 2, /*BUSY=D2*/ 4));
+// grey levels parallel IF e-papers on Waveshare e-Paper IT8951 Driver HAT
+// HRDY -> 4, RST -> 2, CS -> SS(15), SCK -> SCK(14), MOSI -> MOSI(D7(13)), MISO -> MISO(D6(12)), GND -> GND, 5V -> 5V
+// note: 5V supply needs to be exact and strong; 5V pin of USB powered Wemos D1 mini doesn't work!
+////GxEPD2_BW<GxEPD2_it60, GxEPD2_it60::HEIGHT / 8> display(GxEPD2_it60(/*CS=5*/ SS, /*DC=*/ 0, /*RST=*/ 2, /*BUSY=*/ 4));
+
+// ***** for mapping of Waveshare e-Paper ESP8266 Driver Board *****
+// select one , can use full buffer size (full HEIGHT)
+//GxEPD2_BW<GxEPD2_154, GxEPD2_154::HEIGHT> display(GxEPD2_154(/*CS=15*/ SS, /*DC=4*/ 4, /*RST=5*/ 5, /*BUSY=16*/ 16));
+//GxEPD2_BW<GxEPD2_213, GxEPD2_213::HEIGHT> display(GxEPD2_213(/*CS=15*/ SS, /*DC=4*/ 4, /*RST=5*/ 5, /*BUSY=16*/ 16)); // GDE0213B1, phased out
+//GxEPD2_BW<GxEPD2_213_B72, GxEPD2_213_B72::HEIGHT> display(GxEPD2_213_B72(/*CS=15*/ SS, /*DC=4*/ 4, /*RST=5*/ 5, /*BUSY=16*/ 16)); // GDEH0213B72
+//GxEPD2_BW<GxEPD2_213_flex, GxEPD2_213_flex::HEIGHT> display(GxEPD2_213_flex(/*CS=15*/ SS, /*DC=4*/ 4, /*RST=5*/ 5, /*BUSY=16*/ 16)); // GDEW0213I5F
+//GxEPD2_BW<GxEPD2_290, GxEPD2_290::HEIGHT> display(GxEPD2_290(/*CS=15*/ SS, /*DC=4*/ 4, /*RST=5*/ 5, /*BUSY=16*/ 16));
+//GxEPD2_BW<GxEPD2_290_T5, GxEPD2_290_T5::HEIGHT> display(GxEPD2_290_T5(/*CS=15*/ SS, /*DC=4*/ 4, /*RST=5*/ 5, /*BUSY=16*/ 16)); // GDEW029T5
+//GxEPD2_BW<GxEPD2_270, GxEPD2_270::HEIGHT> display(GxEPD2_270(/*CS=15*/ SS, /*DC=4*/ 4, /*RST=5*/ 5, /*BUSY=16*/ 16));
+//GxEPD2_BW<GxEPD2_420, GxEPD2_420::HEIGHT> display(GxEPD2_420(/*CS=15*/ SS, /*DC=4*/ 4, /*RST=5*/ 5, /*BUSY=16*/ 16));
+// can use only half buffer size
+////GxEPD2_BW < GxEPD2_583, GxEPD2_583::HEIGHT / 2 > display(GxEPD2_583(/*CS=15*/ SS, /*DC=4*/ 4, /*RST=5*/ 5, /*BUSY=16*/ 16));
+////GxEPD2_BW < GxEPD2_750, GxEPD2_750::HEIGHT / 2 > display(GxEPD2_750(/*CS=15*/ SS, /*DC=4*/ 4, /*RST=5*/ 5, /*BUSY=16*/ 16));
+// 3-color e-papers
+//GxEPD2_3C<GxEPD2_154c, GxEPD2_154c::HEIGHT> display(GxEPD2_154c(/*CS=15*/ SS, /*DC=4*/ 4, /*RST=5*/ 5, /*BUSY=16*/ 16));
+//GxEPD2_3C<GxEPD2_213c, GxEPD2_213c::HEIGHT> display(GxEPD2_213c(/*CS=15*/ SS, /*DC=4*/ 4, /*RST=5*/ 5, /*BUSY=16*/ 16));
+//GxEPD2_3C<GxEPD2_290c, GxEPD2_290c::HEIGHT> display(GxEPD2_290c(/*CS=15*/ SS, /*DC=4*/ 4, /*RST=5*/ 5, /*BUSY=16*/ 16));
+//GxEPD2_3C<GxEPD2_270c, GxEPD2_270c::HEIGHT> display(GxEPD2_270c(/*CS=15*/ SS, /*DC=4*/ 4, /*RST=5*/ 5, /*BUSY=16*/ 16));
+// can use only half buffer size
+////GxEPD2_3C<GxEPD2_420c, GxEPD2_420c::HEIGHT / 2> display(GxEPD2_420c(/*CS=15*/ SS, /*DC=4*/ 4, /*RST=5*/ 5, /*BUSY=16*/ 16));
+// can use only quarter buffer size
+////GxEPD2_3C<GxEPD2_583c, GxEPD2_583c::HEIGHT / 4> display(GxEPD2_583c(/*CS=15*/ SS, /*DC=4*/ 4, /*RST=5*/ 5, /*BUSY=16*/ 16));
+////GxEPD2_3C<GxEPD2_750c, GxEPD2_750c::HEIGHT / 4> display(GxEPD2_750c(/*CS=15*/ SS, /*DC=4*/ 4, /*RST=5*/ 5, /*BUSY=16*/ 16));
+#endif
+
+#if defined(ESP32)
+// select one and adapt to your mapping, can use full buffer size (full HEIGHT)
+//GxEPD2_BW<GxEPD2_154, GxEPD2_154::HEIGHT> display(GxEPD2_154(/*CS=5*/ SS, /*DC=*/ 17, /*RST=*/ 16, /*BUSY=*/ 4));
+//GxEPD2_BW<GxEPD2_213, GxEPD2_213::HEIGHT> display(GxEPD2_213(/*CS=5*/ SS, /*DC=*/ 17, /*RST=*/ 16, /*BUSY=*/ 4)); // GDE0213B1, phased out
+//GxEPD2_BW<GxEPD2_213_B72, GxEPD2_213_B72::HEIGHT> display(GxEPD2_213_B72(/*CS=5*/ SS, /*DC=*/ 17, /*RST=*/ 16, /*BUSY=*/ 4)); // GDEH0213B72
+//GxEPD2_BW<GxEPD2_213_flex, GxEPD2_213_flex::HEIGHT> display(GxEPD2_213_flex(/*CS=5*/ SS, /*DC=*/ 17, /*RST=*/ 16, /*BUSY=*/ 4)); // GDEW0213I5F
+//GxEPD2_BW<GxEPD2_290, GxEPD2_290::HEIGHT> display(GxEPD2_290(/*CS=5*/ SS, /*DC=*/ 17, /*RST=*/ 16, /*BUSY=*/ 4));
+//GxEPD2_BW<GxEPD2_290_T5, GxEPD2_290_T5::HEIGHT> display(GxEPD2_290_T5(/*CS=5*/ SS, /*DC=*/ 17, /*RST=*/ 16, /*BUSY=*/ 4)); // GDEW029T5
+//GxEPD2_BW<GxEPD2_270, GxEPD2_270::HEIGHT> display(GxEPD2_270(/*CS=5*/ SS, /*DC=*/ 17, /*RST=*/ 16, /*BUSY=*/ 4));
+//GxEPD2_BW<GxEPD2_420, GxEPD2_420::HEIGHT> display(GxEPD2_420(/*CS=5*/ SS, /*DC=*/ 17, /*RST=*/ 16, /*BUSY=*/ 4));
+//GxEPD2_BW<GxEPD2_583, GxEPD2_583::HEIGHT> display(GxEPD2_583(/*CS=5*/ SS, /*DC=*/ 17, /*RST=*/ 16, /*BUSY=*/ 4));
+//GxEPD2_BW<GxEPD2_750, GxEPD2_750::HEIGHT> display(GxEPD2_750(/*CS=5*/ SS, /*DC=*/ 17, /*RST=*/ 16, /*BUSY=*/ 4));
+// 3-color e-papers
+//GxEPD2_3C<GxEPD2_154c, GxEPD2_154c::HEIGHT> display(GxEPD2_154c(/*CS=5*/ SS, /*DC=*/ 17, /*RST=*/ 16, /*BUSY=*/ 4));
+//GxEPD2_3C<GxEPD2_213c, GxEPD2_213c::HEIGHT> display(GxEPD2_213c(/*CS=5*/ SS, /*DC=*/ 17, /*RST=*/ 16, /*BUSY=*/ 4));
+//GxEPD2_3C<GxEPD2_290c, GxEPD2_290c::HEIGHT> display(GxEPD2_290c(/*CS=5*/ SS, /*DC=*/ 17, /*RST=*/ 16, /*BUSY=*/ 4));
+//GxEPD2_3C<GxEPD2_270c, GxEPD2_270c::HEIGHT> display(GxEPD2_270c(/*CS=5*/ SS, /*DC=*/ 17, /*RST=*/ 16, /*BUSY=*/ 4));
+//GxEPD2_3C<GxEPD2_420c, GxEPD2_420c::HEIGHT> display(GxEPD2_420c(/*CS=5*/ SS, /*DC=*/ 17, /*RST=*/ 16, /*BUSY=*/ 4));
+//GxEPD2_3C<GxEPD2_583c, GxEPD2_583c::HEIGHT> display(GxEPD2_583c(/*CS=5*/ SS, /*DC=*/ 17, /*RST=*/ 16, /*BUSY=*/ 4));
+//GxEPD2_3C<GxEPD2_750c, GxEPD2_750c::HEIGHT> display(GxEPD2_750c(/*CS=5*/ SS, /*DC=*/ 17, /*RST=*/ 16, /*BUSY=*/ 4));
+// grey levels parallel IF e-papers on Waveshare e-Paper IT8951 Driver HAT
+// HRDY -> 4, RST -> 16, CS -> SS(5), SCK -> SCK(18), MOSI -> MOSI(23), MISO -> MISO(19), GND -> GND, 5V -> 5V
+// note: 5V supply needs to be exact and strong; 5V over diode from USB (e.g. Wemos D1 mini) doesn't work!
+//GxEPD2_BW<GxEPD2_it60, GxEPD2_it60::HEIGHT> display(GxEPD2_it60(/*CS=5*/ SS, /*DC=*/ 17, /*RST=*/ 16, /*BUSY=*/ 4));
+#endif
+
+#if defined(_BOARD_GENERIC_STM32F103C_H_)
+#define MAX_DISPAY_BUFFER_SIZE 15000ul // ~15k is a good compromise
+#define MAX_HEIGHT(EPD) (EPD::HEIGHT <= MAX_DISPAY_BUFFER_SIZE / (EPD::WIDTH / 8) ? EPD::HEIGHT : MAX_DISPAY_BUFFER_SIZE / (EPD::WIDTH / 8))
+// select one and adapt to your mapping
+//GxEPD2_BW<GxEPD2_154, MAX_HEIGHT(GxEPD2_154)> display(GxEPD2_154(/*CS=4*/ SS, /*DC=*/ 3, /*RST=*/ 2, /*BUSY=*/ 1));
+//GxEPD2_BW<GxEPD2_213, MAX_HEIGHT(GxEPD2_213)> display(GxEPD2_213(/*CS=4*/ SS, /*DC=*/ 3, /*RST=*/ 2, /*BUSY=*/ 1)); // GDE0213B1, phased out
+//GxEPD2_BW<GxEPD2_213_B72, MAX_HEIGHT(GxEPD2_213_B72)> display(GxEPD2_213_B72(/*CS=4*/ SS, /*DC=*/ 3, /*RST=*/ 2, /*BUSY=*/ 1)); // GDEH0213B72
+//GxEPD2_BW<GxEPD2_213_flex, MAX_HEIGHT(GxEPD2_213_flex)> display(GxEPD2_213_flex(/*CS=4*/ SS, /*DC=*/ 3, /*RST=*/ 2, /*BUSY=*/ 1)); // GDEW0213I5F
+//GxEPD2_BW<GxEPD2_290, MAX_HEIGHT(GxEPD2_290)> display(GxEPD2_290(/*CS=4*/ SS, /*DC=*/ 3, /*RST=*/ 2, /*BUSY=*/ 1));
+//GxEPD2_BW<GxEPD2_290_T5, MAX_HEIGHT(GxEPD2_290_T5)> display(GxEPD2_290_T5(/*CS=4*/ SS, /*DC=*/ 3, /*RST=*/ 2, /*BUSY=*/ 1)); // GDEW029T5
+//GxEPD2_BW<GxEPD2_270, MAX_HEIGHT(GxEPD2_270)> display(GxEPD2_270(/*CS=4*/ SS, /*DC=*/ 3, /*RST=*/ 2, /*BUSY=*/ 1));
+//GxEPD2_BW<GxEPD2_420, MAX_HEIGHT(GxEPD2_420)> display(GxEPD2_420(/*CS=4*/ SS, /*DC=*/ 3, /*RST=*/ 2, /*BUSY=*/ 1));
+////GxEPD2_BW<GxEPD2_583, MAX_HEIGHT(GxEPD2_583)> display(GxEPD2_583(/*CS=4*/ SS, /*DC=*/ 3, /*RST=*/ 2, /*BUSY=*/ 1));
+////GxEPD2_BW<GxEPD2_750, MAX_HEIGHT(GxEPD2_750)> display(GxEPD2_750(/*CS=4*/ SS, /*DC=*/ 3, /*RST=*/ 2, /*BUSY=*/ 1));
+// 3-color e-papers
+#define MAX_HEIGHT_3C(EPD) (EPD::HEIGHT <= (MAX_DISPAY_BUFFER_SIZE / 2) / (EPD::WIDTH / 8) ? EPD::HEIGHT : (MAX_DISPAY_BUFFER_SIZE / 2) / (EPD::WIDTH / 8))
+//GxEPD2_3C<GxEPD2_154c, MAX_HEIGHT_3C(GxEPD2_154c)> display(GxEPD2_154c(/*CS=4*/ SS, /*DC=*/ 3, /*RST=*/ 2, /*BUSY=*/ 1));
+//GxEPD2_3C<GxEPD2_213c, MAX_HEIGHT_3C(GxEPD2_213c)> display(GxEPD2_213c(/*CS=4*/ SS, /*DC=*/ 3, /*RST=*/ 2, /*BUSY=*/ 1));
+//GxEPD2_3C<GxEPD2_290c, MAX_HEIGHT_3C(GxEPD2_290c)> display(GxEPD2_290c(/*CS=4*/ SS, /*DC=*/ 3, /*RST=*/ 2, /*BUSY=*/ 1));
+//GxEPD2_3C<GxEPD2_270c, MAX_HEIGHT_3C(GxEPD2_270c)> display(GxEPD2_270c(/*CS=4*/ SS, /*DC=*/ 3, /*RST=*/ 2, /*BUSY=*/ 1));
+////GxEPD2_3C<GxEPD2_420c, MAX_HEIGHT_3C(GxEPD2_420c)> display(GxEPD2_420c(/*CS=4*/ SS, /*DC=*/ 3, /*RST=*/ 2, /*BUSY=*/ 1));
+////GxEPD2_3C<GxEPD2_583c, MAX_HEIGHT_3C(GxEPD2_583c)> display(GxEPD2_583c(/*CS=4*/ SS, /*DC=*/ 3, /*RST=*/ 2, /*BUSY=*/ 1));
+////GxEPD2_3C<GxEPD2_750c, MAX_HEIGHT_3C(GxEPD2_750c)> display(GxEPD2_750c(/*CS=4*/ SS, /*DC=*/ 3, /*RST=*/ 2, /*BUSY=*/ 1));
+#endif
+
+#include "GxEPD2_boards_added.h"
+//#include "GxEPD2_more_boards_added.h" // private
+
+#if !defined(__AVR) && !defined(_BOARD_GENERIC_STM32F103C_H_)
+
+// comment out unused bitmaps to reduce code space used
+#include "bitmaps/Bitmaps200x200.h" // 1.54" b/w
+#include "bitmaps/Bitmaps104x212.h" // 2.13" b/w flexible GDEW0213I5F
+#include "bitmaps/Bitmaps128x250.h" // 2.13" b/w
+#include "bitmaps/Bitmaps128x296.h" // 2.9"  b/w
+#include "bitmaps/Bitmaps176x264.h" // 2.7"  b/w
+#include "bitmaps/Bitmaps400x300.h" // 4.2"  b/w
+#include "bitmaps/Bitmaps640x384.h" // 7.5"  b/w
+// 3-color
+#include "bitmaps/Bitmaps3c200x200.h" // 1.54" b/w/r
+#include "bitmaps/Bitmaps3c104x212.h" // 2.13" b/w/r
+#include "bitmaps/Bitmaps3c128x296.h" // 2.9"  b/w/r
+#include "bitmaps/Bitmaps3c176x264.h" // 2.7"  b/w/r
+#include "bitmaps/Bitmaps3c400x300.h" // 4.2"  b/w/r
+#if defined(ESP8266) || defined(ESP32)
+#include "bitmaps/WS_Bitmaps800x600.h" // 6.0"  grey
+#endif
+
+#else
+
+// select only one to fit in code space
+#include "bitmaps/Bitmaps200x200.h" // 1.54" b/w
+//#include "bitmaps/Bitmaps104x212.h" // 2.13" b/w flexible GDEW0213I5F
+//#include "bitmaps/Bitmaps128x250.h" // 2.13" b/w
+//#include "bitmaps/Bitmaps128x296.h" // 2.9"  b/w
+//#include "bitmaps/Bitmaps176x264.h" // 2.7"  b/w
+////#include "bitmaps/Bitmaps400x300.h" // 4.2"  b/w // not enough code space
+////#include "bitmaps/Bitmaps640x384.h" // 7.5"  b/w // not enough code space
+// 3-color
+//#include "bitmaps/Bitmaps3c200x200.h" // 1.54" b/w/r
+//#include "bitmaps/Bitmaps3c104x212.h" // 2.13" b/w/r
+//#include "bitmaps/Bitmaps3c128x296.h" // 2.9"  b/w/r
+//#include "bitmaps/Bitmaps3c176x264.h" // 2.7"  b/w/r
+////#include "bitmaps/Bitmaps3c400x300.h" // 4.2"  b/w/r // not enough code space
+
+#endif
+
+void setup()
+{
+  Serial.begin(115200);
+  Serial.println();
+  Serial.println("setup");
+  delay(100);
+  display.init(115200);
+  // first update should be full refresh
+  helloWorld();
+  delay(1000);
+  // partial refresh mode can be used to full screen,
+  // effective if display panel hasFastPartialUpdate
+  helloFullScreenPartialMode();
+  delay(1000);
+  helloArduino();
+  delay(1000);
+  helloEpaper();
+  delay(1000);
+  //helloValue(123.9, 1);
+  //delay(1000);
+  showFont("FreeMonoBold9pt7b", &FreeMonoBold9pt7b);
+  delay(1000);
+  drawBitmaps();
+  if (display.epd2.hasPartialUpdate)
+  {
+    showPartialUpdate();
+    delay(1000);
+  } // else // on GDEW0154Z04 only full update available, doesn't look nice
+  //drawCornerTest();
+  //showBox(16, 16, 48, 32, false);
+  //showBox(16, 56, 48, 32, true);
+  display.powerOff();
+  deepSleepTest();
+  Serial.println("setup done");
+}
+
+void loop()
+{
+}
+
+// note for partial update window and setPartialWindow() method:
+// partial update window size and position is on byte boundary in physical x direction
+// the size is increased in setPartialWindow() if x or w are not multiple of 8 for even rotation, y or h for odd rotation
+// see also comment in GxEPD2_BW.h, GxEPD2_3C.h or GxEPD2_GFX.h for method setPartialWindow()
+
+const char HelloWorld[] = "Hello World!";
+const char HelloArduino[] = "Hello Arduino!";
+const char HelloEpaper[] = "Hello E-Paper!";
+
+void helloWorld()
+{
+  //Serial.println("helloWorld");
+  display.setRotation(1);
+  display.setFont(&FreeMonoBold9pt7b);
+  display.setTextColor(GxEPD_BLACK);
+  int16_t tbx, tby; uint16_t tbw, tbh;
+  display.getTextBounds(HelloWorld, 0, 0, &tbx, &tby, &tbw, &tbh);
+  // center bounding box by transposition of origin:
+  uint16_t x = ((display.width() - tbw) / 2) - tbx;
+  uint16_t y = ((display.height() - tbh) / 2) - tby;
+  // full window mode is the initial mode, set it anyway
+  display.setFullWindow();
+  display.fillScreen(GxEPD_WHITE);
+  display.setCursor(x, y);
+  display.print(HelloWorld);
+  display.display(false); // full update
+  //Serial.println("helloWorld done");
+}
+
+void helloWorldForDummiesNotPaged()
+{
+  //Serial.println("helloWorld");
+  const char text[] = "Hello World!";
+  // most e-papers have width < height (portrait) as native orientation, especially the small ones
+  // in GxEPD2 rotation 0 is used for native orientation (most TFT libraries use 0 fix for portrait orientation)
+  // set rotation to 1 (rotate right 90 degrees) to have enough space on small displays (landscape)
+  display.setRotation(1);
+  // select a suitable font in Adafruit_GFX
+  display.setFont(&FreeMonoBold9pt7b);
+  // on e-papers black on white is more pleasant to read
+  display.setTextColor(GxEPD_BLACK);
+  // Adafruit_GFX has a handy method getTextBounds() to determine the boundary box for a text for the actual font
+  int16_t tbx, tby; uint16_t tbw, tbh; // boundary box window
+  display.getTextBounds(text, 0, 0, &tbx, &tby, &tbw, &tbh); // it works for origin 0, 0, fortunately (negative tby!)
+  // center bounding box by transposition of origin:
+  uint16_t x = ((display.width() - tbw) / 2) - tbx;
+  uint16_t y = ((display.height() - tbh) / 2) - tby;
+  // full window mode is the initial mode, set it anyway
+  display.setFullWindow();
+  // here we use full buffered drawing
+  // only part of the display is used if page_height is less than HEIGHT
+  display.fillScreen(GxEPD_WHITE); // set the background to white (fill the buffer with value for white)
+  display.setCursor(x, y); // set the postition to start printing text
+  display.print(text); // print some text
+  // tell the graphics class to transfer the buffer content (page) to the controller buffer
+  // and to refresh to the screen
+  display.display(false); // full update
+  //Serial.println("helloWorld done");
+}
+
+void helloFullScreenPartialMode()
+{
+  //Serial.println("helloFullScreenPartialMode");
+  const char fullscreen[] = "full screen update";
+  const char fpm[] = "fast partial mode";
+  const char spm[] = "slow partial mode";
+  const char npm[] = "no partial mode";
+  // full window mode is the initial mode, set it anyway
+  display.setFullWindow();
+  display.setRotation(1);
+  display.setFont(&FreeMonoBold9pt7b);
+  display.setTextColor(GxEPD_BLACK);
+  const char* updatemode;
+  if (display.epd2.hasFastPartialUpdate)
+  {
+    updatemode = fpm;
+  }
+  else if (display.epd2.hasPartialUpdate)
+  {
+    updatemode = spm;
+  }
+  else
+  {
+    updatemode = npm;
+  }
+  // do this outside of the loop
+  int16_t tbx, tby; uint16_t tbw, tbh;
+  // center update text
+  display.getTextBounds(fullscreen, 0, 0, &tbx, &tby, &tbw, &tbh);
+  uint16_t utx = ((display.width() - tbw) / 2) - tbx;
+  uint16_t uty = ((display.height() / 4) - tbh / 2) - tby;
+  // center update mode
+  display.getTextBounds(updatemode, 0, 0, &tbx, &tby, &tbw, &tbh);
+  uint16_t umx = ((display.width() - tbw) / 2) - tbx;
+  uint16_t umy = ((display.height() * 3 / 4) - tbh / 2) - tby;
+  // center HelloWorld
+  display.getTextBounds(HelloWorld, 0, 0, &tbx, &tby, &tbw, &tbh);
+  uint16_t hwx = ((display.width() - tbw) / 2) - tbx;
+  uint16_t hwy = ((display.height() - tbh) / 2) - tby;
+  display.fillScreen(GxEPD_WHITE);
+  display.setCursor(hwx, hwy);
+  display.print(HelloWorld);
+  display.setCursor(utx, uty);
+  display.print(fullscreen);
+  display.setCursor(umx, umy);
+  display.print(updatemode);
+  display.display(true); // partial update
+  //Serial.println("helloFullScreenPartialMode done");
+}
+
+void helloArduino()
+{
+  //Serial.println("helloArduino");
+  display.setRotation(1);
+  display.setFont(&FreeMonoBold9pt7b);
+  display.setTextColor(display.epd2.hasColor ? GxEPD_RED : GxEPD_BLACK);
+  int16_t tbx, tby; uint16_t tbw, tbh;
+  // align with centered HelloWorld
+  display.getTextBounds(HelloWorld, 0, 0, &tbx, &tby, &tbw, &tbh);
+  uint16_t x = ((display.width() - tbw) / 2) - tbx;
+  // height might be different
+  display.getTextBounds(HelloArduino, 0, 0, &tbx, &tby, &tbw, &tbh);
+  uint16_t y = ((display.height() / 4) - tbh / 2) - tby; // y is base line!
+  // make the window big enough to cover (overwrite) descenders of previous text
+  uint16_t wh = FreeMonoBold9pt7b.yAdvance;
+  uint16_t wy = (display.height() / 4) - wh / 2;
+  // full window mode is the initial mode, set it anyway
+  display.setFullWindow();
+  // DO NOT display.fillScreen(GxEPD_WHITE); keep current content!
+  display.fillRect(0, wy, display.width(), wh, GxEPD_WHITE); // clear rect instead
+  display.setCursor(x, y);
+  display.print(HelloArduino);
+  display.displayWindow(0, wy, display.width(), wh);
+  delay(1000);
+  //Serial.println("helloArduino done");
+}
+
+void helloEpaper()
+{
+  //Serial.println("helloEpaper");
+  display.setRotation(1);
+  display.setFont(&FreeMonoBold9pt7b);
+  display.setTextColor(display.epd2.hasColor ? GxEPD_RED : GxEPD_BLACK);
+  int16_t tbx, tby; uint16_t tbw, tbh;
+  // align with centered HelloWorld
+  display.getTextBounds(HelloWorld, 0, 0, &tbx, &tby, &tbw, &tbh);
+  uint16_t x = ((display.width() - tbw) / 2) - tbx;
+  // height might be different
+  display.getTextBounds(HelloEpaper, 0, 0, &tbx, &tby, &tbw, &tbh);
+  uint16_t y = (display.height() * 3 / 4) + tbh / 2; // y is base line!
+  // make the window big enough to cover (overwrite) descenders of previous text
+  uint16_t wh = FreeMonoBold9pt7b.yAdvance;
+  uint16_t wy = (display.height() * 3 / 4) - wh / 2;
+  // full window mode is the initial mode, set it anyway
+  display.setFullWindow();
+  // DO NOT display.fillScreen(GxEPD_WHITE); keep current content!
+  display.fillRect(0, wy, display.width(), wh, GxEPD_WHITE); // clear rect instead
+  display.setCursor(x, y);
+  display.print(HelloEpaper);
+  display.displayWindow(0, wy, display.width(), wh);
+  //Serial.println("helloEpaper done");
+}
+
+#if defined(ESP8266) || defined(ESP32)
+#include <StreamString.h>
+#define PrintString StreamString
+#else
+class PrintString : public Print, public String
+{
+  public:
+    size_t write(uint8_t data) override
+    {
+      return concat(char(data));
+    };
+};
+#endif
+
+void helloValue(double v, int digits)
+{
+  //Serial.println("helloValue");
+  display.setRotation(1);
+  display.setFont(&FreeMonoBold9pt7b);
+  display.setTextColor(display.epd2.hasColor ? GxEPD_RED : GxEPD_BLACK);
+  PrintString valueString;
+  valueString.print(v, digits);
+  int16_t tbx, tby; uint16_t tbw, tbh;
+  display.getTextBounds(valueString, 0, 0, &tbx, &tby, &tbw, &tbh);
+  uint16_t x = ((display.width() - tbw) / 2) - tbx;
+  uint16_t y = (display.height() * 3 / 4) + tbh / 2; // y is base line!
+  // show what happens, if we use the bounding box for partial window
+  uint16_t wx = (display.width() - tbw) / 2;
+  uint16_t wy = (display.height() * 3 / 4) - tbh / 2;
+  // full window mode is the initial mode, set it anyway
+  display.setFullWindow();
+  // DO NOT display.fillScreen(GxEPD_WHITE); keep current content!
+  display.fillRect(wx, wy, tbw, tbh, GxEPD_WHITE); // clear rect instead
+  display.setCursor(x, y);
+  display.print(valueString);
+  display.displayWindow(wx, wy, tbw, tbh);
+  delay(2000);
+  // make the partial window big enough to cover the previous text
+  uint16_t ww = tbw; // remember window width
+  display.getTextBounds(HelloEpaper, 0, 0, &tbx, &tby, &tbw, &tbh);
+  // adjust, because HelloEpaper was aligned, not centered (could calculate this to be precise)
+  ww = max(ww, uint16_t(tbw + 12)); // 12 seems ok
+  wx = (display.width() - tbw) / 2;
+  // make the window big enough to cover (overwrite) descenders of previous text
+  uint16_t wh = FreeMonoBold9pt7b.yAdvance;
+  wy = (display.height() * 3 / 4) - wh / 2;
+  // DO NOT display.fillScreen(GxEPD_WHITE); keep current content!
+  display.fillRect(wx, wy, ww, wh, GxEPD_WHITE); // clear rect instead
+  display.setCursor(x, y);
+  display.print(valueString);
+  display.displayWindow(wx, wy, ww, wh);
+  // alternately use the whole width for partial window
+  //display.displayWindow(wx, wy, display.width(), wh);
+  //Serial.println("helloValue done");
+}
+
+void deepSleepTest()
+{
+  //Serial.println("deepSleepTest");
+  const char hibernating[] = "hibernating ...";
+  const char wokeup[] = "woke up";
+  const char from[] = "from deep sleep";
+  const char again[] = "again";
+  display.setRotation(1);
+  display.setFont(&FreeMonoBold9pt7b);
+  display.setTextColor(GxEPD_BLACK);
+  int16_t tbx, tby; uint16_t tbw, tbh;
+  // center text
+  display.getTextBounds(hibernating, 0, 0, &tbx, &tby, &tbw, &tbh);
+  uint16_t x = ((display.width() - tbw) / 2) - tbx;
+  uint16_t y = ((display.height() - tbh) / 2) - tby;
+  display.setFullWindow();
+  display.fillScreen(GxEPD_WHITE);
+  display.setCursor(x, y);
+  display.print(hibernating);
+  display.display(false); // full update
+  display.hibernate();
+  delay(5000);
+  display.getTextBounds(wokeup, 0, 0, &tbx, &tby, &tbw, &tbh);
+  uint16_t wx = (display.width() - tbw) / 2;
+  uint16_t wy = (display.height() / 3) + tbh / 2; // y is base line!
+  display.getTextBounds(from, 0, 0, &tbx, &tby, &tbw, &tbh);
+  uint16_t fx = (display.width() - tbw) / 2;
+  uint16_t fy = (display.height() * 2 / 3) + tbh / 2; // y is base line!
+  display.fillScreen(GxEPD_WHITE);
+  display.setCursor(wx, wy);
+  display.print(wokeup);
+  display.setCursor(fx, fy);
+  display.print(from);
+  display.display(false); // full update
+  delay(5000);
+  display.getTextBounds(hibernating, 0, 0, &tbx, &tby, &tbw, &tbh);
+  uint16_t hx = (display.width() - tbw) / 2;
+  uint16_t hy = (display.height() / 3) + tbh / 2; // y is base line!
+  display.getTextBounds(again, 0, 0, &tbx, &tby, &tbw, &tbh);
+  uint16_t ax = (display.width() - tbw) / 2;
+  uint16_t ay = (display.height() * 2 / 3) + tbh / 2; // y is base line!
+  display.fillScreen(GxEPD_WHITE);
+  display.setCursor(hx, hy);
+  display.print(hibernating);
+  display.setCursor(ax, ay);
+  display.print(again);
+  display.display(false); // full update
+  display.hibernate();
+  //Serial.println("deepSleepTest done");
+}
+
+void showBox(uint16_t x, uint16_t y, uint16_t w, uint16_t h, bool partial)
+{
+  //Serial.println("showBox");
+  display.setRotation(1);
+  display.setFullWindow();
+  display.fillScreen(GxEPD_WHITE);
+  display.fillRect(x, y, w, h, GxEPD_BLACK);
+  if (partial)
+  {
+    display.displayWindow(x, y, w, h);
+  }
+  else
+  {
+    display.display(false); // full update
+  }
+  //Serial.println("showBox done");
+}
+
+void drawCornerTest()
+{
+  display.setFullWindow();
+  display.setFont(&FreeMonoBold9pt7b);
+  display.setTextColor(GxEPD_BLACK);
+  for (uint16_t r = 0; r <= 4; r++)
+  {
+    display.setRotation(r);
+    display.fillScreen(GxEPD_WHITE);
+    display.fillRect(0, 0, 8, 8, GxEPD_BLACK);
+    display.fillRect(display.width() - 18, 0, 16, 16, GxEPD_BLACK);
+    display.fillRect(display.width() - 25, display.height() - 25, 24, 24, GxEPD_BLACK);
+    display.fillRect(0, display.height() - 33, 32, 32, GxEPD_BLACK);
+    display.setCursor(display.width() / 2, display.height() / 2);
+    display.print(display.getRotation());
+    display.display(false); // full update
+    delay(2000);
+  }
+}
+
+void showFont(const char name[], const GFXfont* f)
+{
+  display.setFullWindow();
+  display.setRotation(0);
+  display.setTextColor(GxEPD_BLACK);
+  drawFont(name, f);
+  display.display(false); // full update
+}
+
+void drawFont(const char name[], const GFXfont* f)
+{
+  //display.setRotation(0);
+  display.fillScreen(GxEPD_WHITE);
+  display.setTextColor(GxEPD_BLACK);
+  display.setFont(f);
+  display.setCursor(0, 0);
+  display.println();
+  display.println(name);
+  display.println(" !\"#$%&'()*+,-./");
+  display.println("0123456789:;<=>?");
+  display.println("@ABCDEFGHIJKLMNO");
+  display.println("PQRSTUVWXYZ[\\]^_");
+  if (display.epd2.hasColor)
+  {
+    display.setTextColor(GxEPD_RED);
+  }
+  display.println("`abcdefghijklmno");
+  display.println("pqrstuvwxyz{|}~ ");
+}
+
+// note for partial update window and setPartialWindow() method:
+// partial update window size and position is on byte boundary in physical x direction
+// the size is increased in setPartialWindow() if x or w are not multiple of 8 for even rotation, y or h for odd rotation
+// see also comment in GxEPD2_BW.h, GxEPD2_3C.h or GxEPD2_GFX.h for method setPartialWindow()
+// showPartialUpdate() purposely uses values that are not multiples of 8 to test this
+
+void showPartialUpdate()
+{
+  // some useful background
+  helloWorld();
+  // use asymmetric values for test
+  uint16_t box_x = 10;
+  uint16_t box_y = 15;
+  uint16_t box_w = 70;
+  uint16_t box_h = 20;
+  uint16_t cursor_y = box_y + box_h - 6;
+  float value = 13.95;
+  uint16_t incr = display.epd2.hasFastPartialUpdate ? 1 : 3;
+  display.setFont(&FreeMonoBold9pt7b);
+  display.setTextColor(GxEPD_BLACK);
+  display.setFullWindow();
+  // show where the update box is
+  for (uint16_t r = 0; r < 4; r++)
+  {
+    display.setRotation(r);
+    display.fillRect(box_x, box_y, box_w, box_h, GxEPD_BLACK);
+    //display.fillScreen(GxEPD_BLACK);
+    display.displayWindow(box_x, box_y, box_w, box_h);
+    delay(2000);
+    display.fillRect(box_x, box_y, box_w, box_h, GxEPD_WHITE);
+    display.displayWindow(box_x, box_y, box_w, box_h);
+    delay(1000);
+  }
+  //return;
+  // show updates in the update box
+  for (uint16_t r = 0; r < 4; r++)
+  {
+    display.setRotation(r);
+    for (uint16_t i = 1; i <= 10; i += incr)
+    {
+      display.fillRect(box_x, box_y, box_w, box_h, GxEPD_WHITE);
+      display.setCursor(box_x, cursor_y);
+      display.print(value * i, 2);
+      display.displayWindow(box_x, box_y, box_w, box_h);
+      delay(500);
+    }
+    delay(1000);
+    display.fillRect(box_x, box_y, box_w, box_h, GxEPD_WHITE);
+    display.displayWindow(box_x, box_y, box_w, box_h);
+    delay(1000);
+  }
+}
+
+
+void drawBitmaps()
+{
+  display.setFullWindow();
+#ifdef _GxBitmaps104x212_H_
+  drawBitmaps104x212();
+#endif
+#ifdef _GxBitmaps128x250_H_
+  drawBitmaps128x250();
+#endif
+#ifdef _GxBitmaps128x296_H_
+  drawBitmaps128x296();
+#endif
+#ifdef _GxBitmaps176x264_H_
+  drawBitmaps176x264();
+#endif
+#ifdef _GxBitmaps400x300_H_
+  drawBitmaps400x300();
+#endif
+#ifdef _GxBitmaps640x384_H_
+  drawBitmaps640x384();
+#endif
+#ifdef _WS_Bitmaps800x600_H_
+  drawBitmaps800x600();
+#endif
+  // 3-color
+#ifdef _GxBitmaps3c104x212_H_
+  drawBitmaps3c104x212();
+#endif
+#ifdef _GxBitmaps3c128x296_H_
+  drawBitmaps3c128x296();
+#endif
+#ifdef _GxBitmaps3c176x264_H_
+  drawBitmaps3c176x264();
+#endif
+#ifdef _GxBitmaps3c400x300_H_
+  drawBitmaps3c400x300();
+#endif
+  // show these after the specific bitmaps
+#ifdef _GxBitmaps200x200_H_
+  drawBitmaps200x200();
+#endif
+  // 3-color
+#ifdef _GxBitmaps3c200x200_H_
+  drawBitmaps3c200x200();
+#endif
+}
+
+#ifdef _GxBitmaps200x200_H_
+void drawBitmaps200x200()
+{
+#if defined(__AVR)
+  const unsigned char* bitmaps[] =
+  {
+    logo200x200, first200x200 //, second200x200, third200x200, fourth200x200, fifth200x200, sixth200x200, senventh200x200, eighth200x200
+  };
+#elif defined(_BOARD_GENERIC_STM32F103C_H_)
+  const unsigned char* bitmaps[] =
+  {
+    logo200x200, first200x200, second200x200, third200x200, fourth200x200, fifth200x200 //, sixth200x200, senventh200x200, eighth200x200
+  };
+#else
+  const unsigned char* bitmaps[] =
+  {
+    logo200x200, first200x200, second200x200, third200x200, fourth200x200, fifth200x200, sixth200x200, senventh200x200, eighth200x200
+  };
+#endif
+  if (display.epd2.panel == GxEPD2::GDEP015OC1)
+  {
+    bool m = display.mirror(true);
+    for (uint16_t i = 0; i < sizeof(bitmaps) / sizeof(char*); i++)
+    {
+      display.fillScreen(GxEPD_WHITE);
+      display.drawInvertedBitmap(0, 0, bitmaps[i], display.epd2.WIDTH, display.epd2.HEIGHT, GxEPD_BLACK);
+      display.display();
+      delay(2000);
+    }
+    display.mirror(m);
+  }
+  //else
+  {
+    bool mirror_y = (display.epd2.panel != GxEPD2::GDE0213B1);
+    display.clearScreen(); // use default for white
+    int16_t x = (int16_t(display.epd2.WIDTH) - 200) / 2;
+    int16_t y = (int16_t(display.epd2.HEIGHT) - 200) / 2;
+    for (uint16_t i = 0; i < sizeof(bitmaps) / sizeof(char*); i++)
+    {
+      display.drawImage(bitmaps[i], x, y, 200, 200, false, mirror_y, true);
+      delay(2000);
+    }
+  }
+  bool mirror_y = (display.epd2.panel != GxEPD2::GDE0213B1);
+  for (uint16_t i = 0; i < sizeof(bitmaps) / sizeof(char*); i++)
+  {
+    int16_t x = -60;
+    int16_t y = -60;
+    for (uint16_t j = 0; j < 10; j++)
+    {
+      display.writeScreenBuffer(); // use default for white
+      display.writeImage(bitmaps[i], x, y, 200, 200, false, mirror_y, true);
+      display.refresh(true);
+      if (display.epd2.hasFastPartialUpdate)
+      {
+        // for differential update: set previous buffer equal to current buffer in controller
+        display.epd2.writeScreenBufferAgain(); // use default for white
+        display.epd2.writeImageAgain(bitmaps[i], x, y, 200, 200, false, mirror_y, true);
+      }
+      delay(2000);
+      x += 40;
+      y += 40;
+      if ((x >= int16_t(display.epd2.WIDTH)) || (y >= int16_t(display.epd2.HEIGHT))) break;
+    }
+    if (!display.epd2.hasFastPartialUpdate) break; // comment out for full show
+    break; // comment out for full show
+  }
+  display.writeScreenBuffer(); // use default for white
+  display.writeImage(bitmaps[0], int16_t(0), 0, 200, 200, false, mirror_y, true);
+  display.writeImage(bitmaps[0], int16_t(int16_t(display.epd2.WIDTH) - 200), int16_t(display.epd2.HEIGHT) - 200, 200, 200, false, mirror_y, true);
+  display.refresh(true);
+  delay(2000);
+}
+#endif
+
+#ifdef _GxBitmaps104x212_H_
+void drawBitmaps104x212()
+{
+#if !defined(__AVR)
+  const unsigned char* bitmaps[] =
+  {
+    WS_Bitmap104x212, Bitmap104x212_1, Bitmap104x212_2, Bitmap104x212_3
+  };
+#else
+  const unsigned char* bitmaps[] =
+  {
+    WS_Bitmap104x212, Bitmap104x212_1, Bitmap104x212_2, Bitmap104x212_3
+  };
+#endif
+  if (display.epd2.panel == GxEPD2::GDEW0213I5F)
+  {
+    for (uint16_t i = 0; i < sizeof(bitmaps) / sizeof(char*); i++)
+    {
+      display.fillScreen(GxEPD_WHITE);
+      display.drawBitmap(0, 0, bitmaps[i], display.epd2.WIDTH, display.epd2.HEIGHT, GxEPD_BLACK);
+      display.display();
+      delay(2000);
+    }
+  }
+}
+#endif
+
+#ifdef _GxBitmaps128x250_H_
+void drawBitmaps128x250()
+{
+#if !defined(__AVR)
+  const unsigned char* bitmaps[] =
+  {
+    Bitmap128x250_1, logo128x250, first128x250, second128x250, third128x250
+  };
+#else
+  const unsigned char* bitmaps[] =
+  {
+    Bitmap128x250_1, logo128x250, first128x250, second128x250, third128x250
+  };
+#endif
+  if ((display.epd2.panel == GxEPD2::GDE0213B1) || (display.epd2.panel == GxEPD2::GDEH0213B72))
+  {
+    bool m = display.mirror(true);
+    for (uint16_t i = 0; i < sizeof(bitmaps) / sizeof(char*); i++)
+    {
+      display.fillScreen(GxEPD_WHITE);
+      display.drawInvertedBitmap(0, 0, bitmaps[i], display.epd2.WIDTH, display.epd2.HEIGHT, GxEPD_BLACK);
+      display.display();
+      delay(2000);
+    }
+    display.mirror(m);
+  }
+}
+#endif
+
+#ifdef _GxBitmaps128x296_H_
+void drawBitmaps128x296()
+{
+#if !defined(__AVR)
+  const unsigned char* bitmaps[] =
+  {
+    Bitmap128x296_1, logo128x296, first128x296, second128x296, third128x296
+  };
+#else
+  const unsigned char* bitmaps[] =
+  {
+    Bitmap128x296_1, logo128x296 //, first128x296, second128x296, third128x296
+  };
+#endif
+  if (display.epd2.panel == GxEPD2::GDEH029A1)
+  {
+    bool m = display.mirror(true);
+    for (uint16_t i = 0; i < sizeof(bitmaps) / sizeof(char*); i++)
+    {
+      display.fillScreen(GxEPD_WHITE);
+      display.drawInvertedBitmap(0, 0, bitmaps[i], display.epd2.WIDTH, display.epd2.HEIGHT, GxEPD_BLACK);
+      display.display();
+      delay(2000);
+    }
+    display.mirror(m);
+  }
+}
+#endif
+
+#ifdef _GxBitmaps176x264_H_
+void drawBitmaps176x264()
+{
+#if !defined(__AVR)
+  const unsigned char* bitmaps[] =
+  {
+    Bitmap176x264_1, Bitmap176x264_2, Bitmap176x264_3, Bitmap176x264_4, Bitmap176x264_5
+  };
+#else
+  const unsigned char* bitmaps[] =
+  {
+    Bitmap176x264_1, Bitmap176x264_2 //, Bitmap176x264_3, Bitmap176x264_4, Bitmap176x264_5
+  };
+#endif
+  if (display.epd2.panel == GxEPD2::GDEW027W3)
+  {
+    for (uint16_t i = 0; i < sizeof(bitmaps) / sizeof(char*); i++)
+    {
+      display.fillScreen(GxEPD_WHITE);
+      display.drawInvertedBitmap(0, 0, bitmaps[i], display.epd2.WIDTH, display.epd2.HEIGHT, GxEPD_BLACK);
+      display.display();
+      delay(2000);
+    }
+  }
+}
+#endif
+
+#ifdef _GxBitmaps400x300_H_
+void drawBitmaps400x300()
+{
+#if !defined(__AVR)
+  const unsigned char* bitmaps[] =
+  {
+    Bitmap400x300_1, Bitmap400x300_2
+  };
+#else
+  const unsigned char* bitmaps[] = {}; // not enough code space
+#endif
+  if (display.epd2.panel == GxEPD2::GDEW042T2)
+  {
+    for (uint16_t i = 0; i < sizeof(bitmaps) / sizeof(char*); i++)
+    {
+      display.fillScreen(GxEPD_WHITE);
+      display.drawInvertedBitmap(0, 0, bitmaps[i], display.epd2.WIDTH, display.epd2.HEIGHT, GxEPD_BLACK);
+      display.display();
+      delay(2000);
+    }
+  }
+}
+#endif
+
+#ifdef _GxBitmaps640x384_H_
+void drawBitmaps640x384()
+{
+#if !defined(__AVR)
+  const unsigned char* bitmaps[] =
+  {
+    Bitmap640x384_1, Bitmap640x384_2
+  };
+#else
+  const unsigned char* bitmaps[] = {}; // not enough code space
+#endif
+  if ((display.epd2.panel == GxEPD2::GDEW075T8) || (display.epd2.panel == GxEPD2::GDEW075Z09))
+  {
+    for (uint16_t i = 0; i < sizeof(bitmaps) / sizeof(char*); i++)
+    {
+      display.fillScreen(GxEPD_WHITE);
+      display.drawInvertedBitmap(0, 0, bitmaps[i], display.epd2.WIDTH, display.epd2.HEIGHT, GxEPD_BLACK);
+      display.display();
+      delay(2000);
+    }
+  }
+}
+#endif
+
+#ifdef _WS_Bitmaps800x600_H_
+void drawBitmaps800x600()
+{
+#if defined(ESP8266) || defined(ESP32)
+  if (display.epd2.panel == GxEPD2::ED060SCT)
+  {
+    //    Serial.print("sizeof(WS_zoo_800x600) is "); Serial.println(sizeof(WS_zoo_800x600));
+    display.drawNative(WS_zoo_800x600, 0, 0, 0, 800, 600, false, false, true);
+    delay(2000);
+    //    Serial.print("sizeof(WS_pic_1200x825) is "); Serial.println(sizeof(WS_pic_1200x825));
+    //    display.drawNative((const uint8_t*)WS_pic_1200x825, 0, 0, 0, 1200, 825, false, false, true);
+    //    delay(2000);
+    //    Serial.print("sizeof(WS_acaa_1024x731) is "); Serial.println(sizeof(WS_acaa_1024x731));
+    //    display.drawNative(WS_acaa_1024x731, 0, 0, 0, 1024, 731, false, false, true);
+    //    delay(2000);
+  }
+#endif
+}
+#endif
+
+struct bitmap_pair
+{
+  const unsigned char* black;
+  const unsigned char* red;
+};
+
+#ifdef _GxBitmaps3c200x200_H_
+void drawBitmaps3c200x200()
+{
+  bitmap_pair bitmap_pairs[] =
+  {
+    //{Bitmap3c200x200_black, Bitmap3c200x200_red},
+    {WS_Bitmap3c200x200_black, WS_Bitmap3c200x200_red}
+  };
+  if (display.epd2.panel == GxEPD2::GDEW0154Z04)
+  {
+    display.fillScreen(GxEPD_WHITE);
+    // Bitmap3c200x200_black has 2 bits per pixel
+    // taken from Adafruit_GFX.cpp, modified
+    int16_t byteWidth = (display.epd2.WIDTH + 7) / 8; // Bitmap scanline pad = whole byte
+    uint8_t byte = 0;
+    for (int16_t j = 0; j < display.epd2.HEIGHT; j++)
+    {
+      for (int16_t i = 0; i < display.epd2.WIDTH; i++)
+      {
+        if (i & 3) byte <<= 2;
+        else
+        {
+#if defined(__AVR) || defined(ESP8266) || defined(ESP32)
+          byte = pgm_read_byte(&Bitmap3c200x200_black[j * byteWidth * 2 + i / 4]);
+#else
+          byte = Bitmap3c200x200_black[j * byteWidth * 2 + i / 4];
+#endif
+        }
+        if (!(byte & 0x80))
+        {
+          display.drawPixel(i, j, GxEPD_BLACK);
+        }
+      }
+    }
+    display.drawInvertedBitmap(0, 0, Bitmap3c200x200_red, display.epd2.WIDTH, display.epd2.HEIGHT, GxEPD_RED);
+    display.display();
+    delay(2000);
+    for (uint16_t i = 0; i < sizeof(bitmap_pairs) / sizeof(bitmap_pair); i++)
+    {
+      display.fillScreen(GxEPD_WHITE);
+      display.drawInvertedBitmap(0, 0, bitmap_pairs[i].black, display.epd2.WIDTH, display.epd2.HEIGHT, GxEPD_BLACK);
+      display.drawInvertedBitmap(0, 0, bitmap_pairs[i].red, display.epd2.WIDTH, display.epd2.HEIGHT, GxEPD_RED);
+      display.display();
+      delay(2000);
+    }
+  }
+  if (display.epd2.hasColor)
+  {
+    display.clearScreen(); // use default for white
+    int16_t x = (int16_t(display.epd2.WIDTH) - 200) / 2;
+    int16_t y = (int16_t(display.epd2.HEIGHT) - 200) / 2;
+    for (uint16_t i = 0; i < sizeof(bitmap_pairs) / sizeof(bitmap_pair); i++)
+    {
+      display.drawImage(bitmap_pairs[i].black, bitmap_pairs[i].red, x, y, 200, 200, false, false, true);
+      delay(2000);
+    }
+    for (uint16_t i = 0; i < sizeof(bitmap_pairs) / sizeof(bitmap_pair); i++)
+    {
+      int16_t x = -60;
+      int16_t y = -60;
+      for (uint16_t j = 0; j < 10; j++)
+      {
+        display.writeScreenBuffer(); // use default for white
+        display.writeImage(bitmap_pairs[i].black, bitmap_pairs[i].red, x, y, 200, 200, false, false, true);
+        display.refresh();
+        delay(1000);
+        x += 40;
+        y += 40;
+        if ((x >= int16_t(display.epd2.WIDTH)) || (y >= int16_t(display.epd2.HEIGHT))) break;
+      }
+    }
+    display.writeScreenBuffer(); // use default for white
+    display.writeImage(bitmap_pairs[0].black, bitmap_pairs[0].red, 0, 0, 200, 200, false, false, true);
+    display.writeImage(bitmap_pairs[0].black, bitmap_pairs[0].red, int16_t(display.epd2.WIDTH) - 200, int16_t(display.epd2.HEIGHT) - 200, 200, 200, false, false, true);
+    display.refresh();
+    delay(2000);
+  }
+}
+#endif
+
+#ifdef _GxBitmaps3c104x212_H_
+void drawBitmaps3c104x212()
+{
+#if !defined(__AVR)
+  bitmap_pair bitmap_pairs[] =
+  {
+    {Bitmap3c104x212_1_black, Bitmap3c104x212_1_red},
+    {Bitmap3c104x212_2_black, Bitmap3c104x212_2_red},
+    {WS_Bitmap3c104x212_black, WS_Bitmap3c104x212_red}
+  };
+#else
+  bitmap_pair bitmap_pairs[] =
+  {
+    {Bitmap3c104x212_1_black, Bitmap3c104x212_1_red},
+    //{Bitmap3c104x212_2_black, Bitmap3c104x212_2_red},
+    {WS_Bitmap3c104x212_black, WS_Bitmap3c104x212_red}
+  };
+#endif
+  if (display.epd2.panel == GxEPD2::GDEW0213Z16)
+  {
+    for (uint16_t i = 0; i < sizeof(bitmap_pairs) / sizeof(bitmap_pair); i++)
+    {
+      display.fillScreen(GxEPD_WHITE);
+      display.drawInvertedBitmap(0, 0, bitmap_pairs[i].black, display.epd2.WIDTH, display.epd2.HEIGHT, GxEPD_BLACK);
+      if (bitmap_pairs[i].red == WS_Bitmap3c104x212_red)
+      {
+        display.drawInvertedBitmap(0, 0, bitmap_pairs[i].red, display.epd2.WIDTH, display.epd2.HEIGHT, GxEPD_RED);
+      }
+      else display.drawBitmap(0, 0, bitmap_pairs[i].red, display.epd2.WIDTH, display.epd2.HEIGHT, GxEPD_RED);
+      display.display();
+      delay(2000);
+    }
+  }
+}
+#endif
+
+#ifdef _GxBitmaps3c128x296_H_
+void drawBitmaps3c128x296()
+{
+#if !defined(__AVR)
+  bitmap_pair bitmap_pairs[] =
+  {
+    {Bitmap3c128x296_1_black, Bitmap3c128x296_1_red},
+    {Bitmap3c128x296_2_black, Bitmap3c128x296_2_red},
+    {WS_Bitmap3c128x296_black, WS_Bitmap3c128x296_red}
+  };
+#else
+  bitmap_pair bitmap_pairs[] =
+  {
+    //{Bitmap3c128x296_1_black, Bitmap3c128x296_1_red},
+    //{Bitmap3c128x296_2_black, Bitmap3c128x296_2_red},
+    {WS_Bitmap3c128x296_black, WS_Bitmap3c128x296_red}
+  };
+#endif
+  if (display.epd2.panel == GxEPD2::GDEW029Z10)
+  {
+    for (uint16_t i = 0; i < sizeof(bitmap_pairs) / sizeof(bitmap_pair); i++)
+    {
+      display.fillScreen(GxEPD_WHITE);
+      display.drawInvertedBitmap(0, 0, bitmap_pairs[i].black, display.epd2.WIDTH, display.epd2.HEIGHT, GxEPD_BLACK);
+      if (bitmap_pairs[i].red == WS_Bitmap3c128x296_red)
+      {
+        display.drawInvertedBitmap(0, 0, bitmap_pairs[i].red, display.epd2.WIDTH, display.epd2.HEIGHT, GxEPD_RED);
+      }
+      else display.drawBitmap(0, 0, bitmap_pairs[i].red, display.epd2.WIDTH, display.epd2.HEIGHT, GxEPD_RED);
+      display.display();
+      delay(2000);
+    }
+  }
+}
+#endif
+
+#ifdef _GxBitmaps3c176x264_H_
+void drawBitmaps3c176x264()
+{
+  bitmap_pair bitmap_pairs[] =
+  {
+    {Bitmap3c176x264_black, Bitmap3c176x264_red}
+  };
+  if (display.epd2.panel == GxEPD2::GDEW027C44)
+  {
+    for (uint16_t i = 0; i < sizeof(bitmap_pairs) / sizeof(bitmap_pair); i++)
+    {
+      display.fillScreen(GxEPD_WHITE);
+      display.drawBitmap(0, 0, bitmap_pairs[i].black, display.epd2.WIDTH, display.epd2.HEIGHT, GxEPD_BLACK);
+      display.drawBitmap(0, 0, bitmap_pairs[i].red, display.epd2.WIDTH, display.epd2.HEIGHT, GxEPD_RED);
+      display.display();
+      delay(2000);
+    }
+  }
+}
+#endif
+
+#ifdef _GxBitmaps3c400x300_H_
+void drawBitmaps3c400x300()
+{
+#if !defined(__AVR)
+  bitmap_pair bitmap_pairs[] =
+  {
+    {Bitmap3c400x300_1_black, Bitmap3c400x300_1_red},
+    {Bitmap3c400x300_2_black, Bitmap3c400x300_2_red},
+    {WS_Bitmap3c400x300_black, WS_Bitmap3c400x300_red}
+  };
+#else
+  bitmap_pair bitmap_pairs[] = {}; // not enough code space
+#endif
+  if (display.epd2.panel == GxEPD2::GDEW042Z15)
+  {
+    for (uint16_t i = 0; i < sizeof(bitmap_pairs) / sizeof(bitmap_pair); i++)
+    {
+      display.fillScreen(GxEPD_WHITE);
+      display.drawInvertedBitmap(0, 0, bitmap_pairs[i].black, display.epd2.WIDTH, display.epd2.HEIGHT, GxEPD_BLACK);
+      display.drawInvertedBitmap(0, 0, bitmap_pairs[i].red, display.epd2.WIDTH, display.epd2.HEIGHT, GxEPD_RED);
+      display.display();
+      delay(2000);
+    }
+  }
+}
+#endif

examples/GxEPD2_NotPagedExample/GxEPD2_boards_added.h

@@ -0,0 +1,129 @@
+// Display Library example for SPI e-paper panels from Dalian Good Display and boards from Waveshare.
+// Requires HW SPI and Adafruit_GFX. Caution: these e-papers require 3.3V supply AND data lines!
+//
+// Display Library based on Demo Example from Good Display: http://www.e-paper-display.com/download_list/downloadcategoryid=34&isMode=false.html
+//
+// Author: Jean-Marc Zingg
+//
+// Version: see library.properties
+//
+// Library: https://github.com/ZinggJM/GxEPD2
+
+#ifndef _GxEPD2_boards_added_H_
+#define _GxEPD2_boards_added_H_
+
+// Arduino DUE
+
+// mapping suggestion for Arduino DUE
+// BUSY -> 7, RST -> 9, DC -> 8, CS-> 77, CLK -> 76, DIN -> 75
+// SPI pins are on 6 pin 2x3 SPI header
+
+#if defined(ARDUINO_ARCH_SAM)
+#define MAX_DISPAY_BUFFER_SIZE 15000ul // ~15k is a good compromise
+#define MAX_HEIGHT(EPD) (EPD::HEIGHT <= MAX_DISPAY_BUFFER_SIZE / (EPD::WIDTH / 8) ? EPD::HEIGHT : MAX_DISPAY_BUFFER_SIZE / (EPD::WIDTH / 8))
+// select one and adapt to your mapping
+//GxEPD2_BW<GxEPD2_154, MAX_HEIGHT(GxEPD2_154)> display(GxEPD2_154(/*CS=77*/ SS, /*DC=*/ 8, /*RST=*/ 9, /*BUSY=*/ 7));
+//GxEPD2_BW<GxEPD2_213, MAX_HEIGHT(GxEPD2_213)> display(GxEPD2_213(/*CS=77*/ SS, /*DC=*/ 8, /*RST=*/ 9, /*BUSY=*/ 7));
+//GxEPD2_BW<GxEPD2_213_flex, MAX_HEIGHT(GxEPD2_213_flex)> display(GxEPD2_213_flex(/*CS=77*/ SS, /*DC=*/ 8, /*RST=*/ 9, /*BUSY=*/ 7)); // GDEW0213I5F
+//GxEPD2_BW<GxEPD2_290, MAX_HEIGHT(GxEPD2_290)> display(GxEPD2_290(/*CS=77*/ SS, /*DC=*/ 8, /*RST=*/ 9, /*BUSY=*/ 7));
+//GxEPD2_BW<GxEPD2_290_T5, MAX_HEIGHT(GxEPD2_290_T5)> display(GxEPD2_290_T5(/*CS=77*/ SS, /*DC=*/ 8, /*RST=*/ 9, /*BUSY=*/ 7)); // GDEW029T5
+//GxEPD2_BW<GxEPD2_270, MAX_HEIGHT(GxEPD2_270)> display(GxEPD2_270(/*CS=77*/ SS, /*DC=*/ 8, /*RST=*/ 9, /*BUSY=*/ 7));
+//GxEPD2_BW<GxEPD2_420, MAX_HEIGHT(GxEPD2_420)> display(GxEPD2_420(/*CS=77*/ SS, /*DC=*/ 8, /*RST=*/ 9, /*BUSY=*/ 7));
+//GxEPD2_BW<GxEPD2_583, MAX_HEIGHT(GxEPD2_583)> display(GxEPD2_583(/*CS=77*/ SS, /*DC=*/ 8, /*RST=*/ 9, /*BUSY=*/ 7));
+//GxEPD2_BW<GxEPD2_750, MAX_HEIGHT(GxEPD2_750)> display(GxEPD2_750(/*CS=77*/ SS, /*DC=*/ 8, /*RST=*/ 9, /*BUSY=*/ 7));
+// 3-color e-papers
+#define MAX_HEIGHT_3C(EPD) (EPD::HEIGHT <= (MAX_DISPAY_BUFFER_SIZE / 2) / (EPD::WIDTH / 8) ? EPD::HEIGHT : (MAX_DISPAY_BUFFER_SIZE / 2) / (EPD::WIDTH / 8))
+//GxEPD2_3C<GxEPD2_154c, MAX_HEIGHT_3C(GxEPD2_154c)> display(GxEPD2_154c(/*CS=77*/ SS, /*DC=*/ 8, /*RST=*/ 9, /*BUSY=*/ 7));
+//GxEPD2_3C<GxEPD2_213c, MAX_HEIGHT_3C(GxEPD2_213c)> display(GxEPD2_213c(/*CS=77*/ SS, /*DC=*/ 8, /*RST=*/ 9, /*BUSY=*/ 7));
+//GxEPD2_3C<GxEPD2_290c, MAX_HEIGHT_3C(GxEPD2_290c)> display(GxEPD2_290c(/*CS=77*/ SS, /*DC=*/ 8, /*RST=*/ 9, /*BUSY=*/ 7));
+//GxEPD2_3C<GxEPD2_270c, MAX_HEIGHT_3C(GxEPD2_270c)> display(GxEPD2_270c(/*CS=77*/ SS, /*DC=*/ 8, /*RST=*/ 9, /*BUSY=*/ 7));
+//GxEPD2_3C<GxEPD2_420c, MAX_HEIGHT_3C(GxEPD2_420c)> display(GxEPD2_420c(/*CS=77*/ SS, /*DC=*/ 8, /*RST=*/ 9, /*BUSY=*/ 7));
+//GxEPD2_3C<GxEPD2_583c, MAX_HEIGHT_3C(GxEPD2_583c)> display(GxEPD2_583c(/*CS=77*/ SS, /*DC=*/ 8, /*RST=*/ 9, /*BUSY=*/ 7));
+//GxEPD2_3C<GxEPD2_750c, MAX_HEIGHT_3C(GxEPD2_750c)> display(GxEPD2_750c(/*CS=77*/ SS, /*DC=*/ 8, /*RST=*/ 9, /*BUSY=*/ 7));
+#endif
+
+// Arduino MKR1000 or MKRZERO
+
+// mapping suggestion for Arduino MKR1000 or MKRZERO
+// note: can't use SS on MKR1000: is defined as 24, should be 4
+// BUSY -> 5, RST -> 6, DC -> 7, CS-> 4, CLK -> 9, DIN -> 8
+
+#if defined(ARDUINO_ARCH_SAMD)
+#define MAX_DISPAY_BUFFER_SIZE 15000ul // ~15k is a good compromise
+#define MAX_HEIGHT(EPD) (EPD::HEIGHT <= MAX_DISPAY_BUFFER_SIZE / (EPD::WIDTH / 8) ? EPD::HEIGHT : MAX_DISPAY_BUFFER_SIZE / (EPD::WIDTH / 8))
+// select one and adapt to your mapping
+//GxEPD2_BW<GxEPD2_154, MAX_HEIGHT(GxEPD2_154)> display(GxEPD2_154(/*CS=4*/ 4, /*DC=*/ 7, /*RST=*/ 6, /*BUSY=*/ 5));
+//GxEPD2_BW<GxEPD2_213, MAX_HEIGHT(GxEPD2_213)> display(GxEPD2_213(/*CS=4*/ 4, /*DC=*/ 7, /*RST=*/ 6, /*BUSY=*/ 5));
+//GxEPD2_BW<GxEPD2_213_flex, MAX_HEIGHT(GxEPD2_213_flex)> display(GxEPD2_213_flex(/*CS=4*/ 4, /*DC=*/ 7, /*RST=*/ 6, /*BUSY=*/ 5)); // GDEW0213I5F
+//GxEPD2_BW<GxEPD2_290, MAX_HEIGHT(GxEPD2_290)> display(GxEPD2_290(/*CS=4*/ 4, /*DC=*/ 7, /*RST=*/ 6, /*BUSY=*/ 5));
+//GxEPD2_BW<GxEPD2_290_T5, MAX_HEIGHT(GxEPD2_290_T5)> display(GxEPD2_290_T5(/*CS=4*/ 4, /*DC=*/ 7, /*RST=*/ 6, /*BUSY=*/ 5)); // GDEW029T5
+//GxEPD2_BW<GxEPD2_270, MAX_HEIGHT(GxEPD2_270)> display(GxEPD2_270(/*CS=4*/ 4, /*DC=*/ 7, /*RST=*/ 6, /*BUSY=*/ 5));
+//GxEPD2_BW<GxEPD2_420, MAX_HEIGHT(GxEPD2_420)> display(GxEPD2_420(/*CS=4*/ 4, /*DC=*/ 7, /*RST=*/ 6, /*BUSY=*/ 5));
+//GxEPD2_BW<GxEPD2_583, MAX_HEIGHT(GxEPD2_583)> display(GxEPD2_583(/*CS=4*/ 4, /*DC=*/ 7, /*RST=*/ 6, /*BUSY=*/ 5));
+//GxEPD2_BW<GxEPD2_750, MAX_HEIGHT(GxEPD2_750)> display(GxEPD2_750(/*CS=4*/ 4, /*DC=*/ 7, /*RST=*/ 6, /*BUSY=*/ 5));
+// 3-color e-papers
+#define MAX_HEIGHT_3C(EPD) (EPD::HEIGHT <= (MAX_DISPAY_BUFFER_SIZE / 2) / (EPD::WIDTH / 8) ? EPD::HEIGHT : (MAX_DISPAY_BUFFER_SIZE / 2) / (EPD::WIDTH / 8))
+//GxEPD2_3C<GxEPD2_154c, MAX_HEIGHT_3C(GxEPD2_154c)> display(GxEPD2_154c(/*CS=4*/ 4, /*DC=*/ 7, /*RST=*/ 6, /*BUSY=*/ 5));
+//GxEPD2_3C<GxEPD2_213c, MAX_HEIGHT_3C(GxEPD2_213c)> display(GxEPD2_213c(/*CS=4*/ 4, /*DC=*/ 7, /*RST=*/ 6, /*BUSY=*/ 5));
+//GxEPD2_3C<GxEPD2_290c, MAX_HEIGHT_3C(GxEPD2_290c)> display(GxEPD2_290c(/*CS=4*/ 4, /*DC=*/ 7, /*RST=*/ 6, /*BUSY=*/ 5));
+//GxEPD2_3C<GxEPD2_270c, MAX_HEIGHT_3C(GxEPD2_270c)> display(GxEPD2_270c(/*CS=4*/ 4, /*DC=*/ 7, /*RST=*/ 6, /*BUSY=*/ 5));
+//GxEPD2_3C<GxEPD2_420c, MAX_HEIGHT_3C(GxEPD2_420c)> display(GxEPD2_420c(/*CS=4*/ 4, /*DC=*/ 7, /*RST=*/ 6, /*BUSY=*/ 5));
+//GxEPD2_3C<GxEPD2_583c, MAX_HEIGHT_3C(GxEPD2_583c)> display(GxEPD2_583c(/*CS=4*/ 4, /*DC=*/ 7, /*RST=*/ 6, /*BUSY=*/ 5));
+//GxEPD2_3C<GxEPD2_750c, MAX_HEIGHT_3C(GxEPD2_750c)> display(GxEPD2_750c(/*CS=4*/ 4, /*DC=*/ 7, /*RST=*/ 6, /*BUSY=*/ 5));
+#endif
+
+// mapping suggestion for ESP32, e.g. LOLIN32 D32 PRO
+// BUSY -> 15, RST -> 2, DC -> 0, CS -> 5, CLK -> SCK(18), DIN -> MOSI(23), GND -> GND, 3.3V -> 3.3V
+// note: use explicit value for CS, as SS is re-defined to TF_CS(4) in pins_arduino.h for Board: "LOLIN D32 PRO"
+
+#if defined(ESP32) && defined(ARDUINO_LOLIN_D32_PRO)
+// select one and adapt to your mapping, can use full buffer size (full HEIGHT)
+//GxEPD2_BW<GxEPD2_154, GxEPD2_154::HEIGHT> display(GxEPD2_154(/*CS=5*/ 5, /*DC=*/ 0, /*RST=*/ 2, /*BUSY=*/ 15));
+//GxEPD2_BW<GxEPD2_213, GxEPD2_213::HEIGHT> display(GxEPD2_213(/*CS=5*/ 5, /*DC=*/ 0, /*RST=*/ 2, /*BUSY=*/ 15));
+//GxEPD2_BW<GxEPD2_213_flex, GxEPD2_213_flex::HEIGHT> display(GxEPD2_213_flex(/*CS=5*/ 5, /*DC=*/ 0, /*RST=*/ 2, /*BUSY=*/ 15)); // GDEW0213I5F
+//GxEPD2_BW<GxEPD2_290, GxEPD2_290::HEIGHT> display(GxEPD2_290(/*CS=5*/ 5, /*DC=*/ 0, /*RST=*/ 2, /*BUSY=*/ 15));
+//GxEPD2_BW<GxEPD2_290_T5, GxEPD2_290_T5::HEIGHT> display(GxEPD2_290_T5(/*CS=5*/ 5, /*DC=*/ 0, /*RST=*/ 2, /*BUSY=*/ 15)); // GDEW029T5
+//GxEPD2_BW<GxEPD2_270, GxEPD2_270::HEIGHT> display(GxEPD2_270(/*CS=5*/ 5, /*DC=*/ 0, /*RST=*/ 2, /*BUSY=*/ 15));
+//GxEPD2_BW<GxEPD2_420, GxEPD2_420::HEIGHT> display(GxEPD2_420(/*CS=5*/ 5, /*DC=*/ 0, /*RST=*/ 2, /*BUSY=*/ 15));
+//GxEPD2_BW<GxEPD2_750, GxEPD2_750::HEIGHT> display(GxEPD2_750(/*CS=5*/ 5, /*DC=*/ 0, /*RST=*/ 2, /*BUSY=*/ 15));
+// 3-color e-papers
+//GxEPD2_3C<GxEPD2_154c, GxEPD2_154c::HEIGHT> display(GxEPD2_154c(/*CS=5*/ 5, /*DC=*/ 0, /*RST=*/ 2, /*BUSY=*/ 15));
+//GxEPD2_3C<GxEPD2_213c, GxEPD2_213c::HEIGHT> display(GxEPD2_213c(/*CS=5*/ 5, /*DC=*/ 0, /*RST=*/ 2, /*BUSY=*/ 15));
+//GxEPD2_3C<GxEPD2_290c, GxEPD2_290c::HEIGHT> display(GxEPD2_290c(/*CS=5*/ 5, /*DC=*/ 0, /*RST=*/ 2, /*BUSY=*/ 15));
+//GxEPD2_3C<GxEPD2_270c, GxEPD2_270c::HEIGHT> display(GxEPD2_270c(/*CS=5*/ 5, /*DC=*/ 0, /*RST=*/ 2, /*BUSY=*/ 15));
+//GxEPD2_3C<GxEPD2_420c, GxEPD2_420c::HEIGHT> display(GxEPD2_420c(/*CS=5*/ 5, /*DC=*/ 0, /*RST=*/ 2, /*BUSY=*/ 15));
+//GxEPD2_3C<GxEPD2_750c, GxEPD2_750c::HEIGHT> display(GxEPD2_750c(/*CS=5*/ 5, /*DC=*/ 0, /*RST=*/ 2, /*BUSY=*/ 15));
+// grey levels parallel IF e-papers on Waveshare e-Paper IT8951 Driver HAT
+// HRDY -> 4, RST -> 16, CS -> 5, SCK -> SCK(18), MOSI -> MOSI(23), MISO -> MISO(19), GND -> GND, 5V -> 5V
+// note: 5V supply needs to be exact and strong; 5V over diode from USB (e.g. Wemos D1 mini) doesn't work!
+//GxEPD2_BW<GxEPD2_it60, GxEPD2_it60::HEIGHT> display(GxEPD2_it60(/*CS=5*/ 5, /*DC=*/ 0, /*RST=*/ 2, /*BUSY=*/ 15));
+#endif
+
+// mapping suggestion for ESP32, e.g. TTGO T8 ESP32-WROVER
+// BUSY -> 4, RST -> 0, DC -> 2, CS -> SS(5), CLK -> SCK(18), DIN -> MOSI(23), GND -> GND, 3.3V -> 3.3V
+// for use with Board: "ESP32 Dev Module":
+
+#if defined(ESP32) && defined(ARDUINO_ESP32_DEV)
+// select one and adapt to your mapping, can use full buffer size (full HEIGHT)
+//GxEPD2_BW<GxEPD2_154, GxEPD2_154::HEIGHT> display(GxEPD2_154(/*CS=5*/ 5, /*DC=*/ 2, /*RST=*/ 0, /*BUSY=*/ 4));
+//GxEPD2_BW<GxEPD2_213, GxEPD2_213::HEIGHT> display(GxEPD2_213(/*CS=5*/ 5, /*DC=*/ 2, /*RST=*/ 0, /*BUSY=*/ 4));
+//GxEPD2_BW<GxEPD2_213_flex, GxEPD2_213_flex::HEIGHT> display(GxEPD2_213_flex(/*CS=5*/ 5, /*DC=*/ 2, /*RST=*/ 0, /*BUSY=*/ 4)); // GDEW0213I5F
+//GxEPD2_BW<GxEPD2_290, GxEPD2_290::HEIGHT> display(GxEPD2_290(/*CS=5*/ 5, /*DC=*/ 2, /*RST=*/ 0, /*BUSY=*/ 4));
+//GxEPD2_BW<GxEPD2_290_T5, GxEPD2_290_T5::HEIGHT> display(GxEPD2_290_T5(/*CS=5*/ 5, /*DC=*/ 2, /*RST=*/ 0, /*BUSY=*/ 4)); // GDEW029T5
+//GxEPD2_BW<GxEPD2_270, GxEPD2_270::HEIGHT> display(GxEPD2_270(/*CS=5*/ 5, /*DC=*/ 2, /*RST=*/ 0, /*BUSY=*/ 4));
+//GxEPD2_BW<GxEPD2_420, GxEPD2_420::HEIGHT> display(GxEPD2_420(/*CS=5*/ 5, /*DC=*/ 2, /*RST=*/ 0, /*BUSY=*/ 4));
+//GxEPD2_BW<GxEPD2_750, GxEPD2_750::HEIGHT> display(GxEPD2_750(/*CS=5*/ 5, /*DC=*/ 2, /*RST=*/ 0, /*BUSY=*/ 4));
+// 3-color e-papers
+//GxEPD2_3C<GxEPD2_154c, GxEPD2_154c::HEIGHT> display(GxEPD2_154c(/*CS=5*/ 5, /*DC=*/ 2, /*RST=*/ 0, /*BUSY=*/ 4));
+//GxEPD2_3C<GxEPD2_213c, GxEPD2_213c::HEIGHT> display(GxEPD2_213c(/*CS=5*/ 5, /*DC=*/ 2, /*RST=*/ 0, /*BUSY=*/ 4));
+//GxEPD2_3C<GxEPD2_290c, GxEPD2_290c::HEIGHT> display(GxEPD2_290c(/*CS=5*/ 5, /*DC=*/ 2, /*RST=*/ 0, /*BUSY=*/ 4));
+//GxEPD2_3C<GxEPD2_270c, GxEPD2_270c::HEIGHT> display(GxEPD2_270c(/*CS=5*/ 5, /*DC=*/ 2, /*RST=*/ 0, /*BUSY=*/ 4));
+//GxEPD2_3C<GxEPD2_420c, GxEPD2_420c::HEIGHT> display(GxEPD2_420c(/*CS=5*/ 5, /*DC=*/ 2, /*RST=*/ 0, /*BUSY=*/ 4));
+//GxEPD2_3C<GxEPD2_750c, GxEPD2_750c::HEIGHT> display(GxEPD2_750c(/*CS=5*/ 5, /*DC=*/ 2, /*RST=*/ 0, /*BUSY=*/ 4));
+// grey levels parallel IF e-papers on Waveshare e-Paper IT8951 Driver HAT
+// HRDY -> 4, RST -> 16, CS -> SS(5), SCK -> SCK(18), MOSI -> MOSI(23), MISO -> MISO(19), GND -> GND, 5V -> 5V
+// note: 5V supply needs to be exact and strong; 5V over diode from USB (e.g. Wemos D1 mini) doesn't work!
+//GxEPD2_BW<GxEPD2_it60, GxEPD2_it60::HEIGHT> display(GxEPD2_it60(/*CS=5*/ 5, /*DC=*/ 2, /*RST=*/ 0, /*BUSY=*/ 4));
+#endif
+
+#endif

extras/Particle/examples/GxEPD2_ParticleExample/project.properties

@@ -1,2 +1,2 @@
 name=GxEPD2_ParticleExample
-dependencies.GxEPD2=1.1.6
+dependencies.GxEPD2=1.1.7

library.properties

@@ -1,5 +1,5 @@
 name=GxEPD2
-version=1.1.6
+version=1.1.7
 author=Jean-Marc Zingg
 maintainer=Jean-Marc Zingg
 sentence=Arduino Display Library for SPI E-Paper displays from Dalian Good Display and Waveshare. 

src/GxEPD2_3C.h

@@ -143,10 +143,27 @@ class GxEPD2_3C : public Adafruit_GFX
     // display buffer content to screen, useful for full screen buffer
     void display(bool partial_update_mode = false)
     {
-      epd2.writeImage(_black_buffer, _color_buffer, 0, 0, WIDTH, HEIGHT);
+      epd2.writeImage(_black_buffer, _color_buffer, 0, 0, WIDTH, _page_height);
       epd2.refresh(partial_update_mode);
     }
 
+    // display part of buffer content to screen, useful for full screen buffer
+    // displayWindow, use parameters according to actual rotation.
+    // x and w should be multiple of 8, for rotation 0 or 2,
+    // y and h should be multiple of 8, for rotation 1 or 3,
+    // else window is increased as needed,
+    // this is an addressing limitation of the e-paper controllers
+    void displayWindow(uint16_t x, uint16_t y, uint16_t w, uint16_t h)
+    {
+      x = gx_uint16_min(x, width());
+      y = gx_uint16_min(y, height());
+      w = gx_uint16_min(w, width() - x);
+      h = gx_uint16_min(h, height() - y);
+      _rotate(x, y, w, h);
+      epd2.writeImagePart(_black_buffer, _color_buffer, x, y, WIDTH, _page_height, x, y, w, h);
+      epd2.refresh(x, y, w, h);
+    }
+
     void setFullWindow()
     {
       _using_partial_mode = false;
@@ -164,12 +181,12 @@ class GxEPD2_3C : public Adafruit_GFX
     void setPartialWindow(uint16_t x, uint16_t y, uint16_t w, uint16_t h)
     {
       if (!epd2.hasPartialUpdate) return;
-      _rotate(x, y, w, h);
+      _pw_x = gx_uint16_min(x, width());
+      _pw_y = gx_uint16_min(y, height());
+      _pw_w = gx_uint16_min(w, width() - _pw_x);
+      _pw_h = gx_uint16_min(h, height() - _pw_y);
+      _rotate(_pw_x, _pw_y, _pw_w, _pw_h);
       _using_partial_mode = true;
-      _pw_x = gx_uint16_min(x, WIDTH);
-      _pw_y = gx_uint16_min(y, HEIGHT);
-      _pw_w = gx_uint16_min(w, WIDTH - _pw_x);
-      _pw_h = gx_uint16_min(h, HEIGHT - _pw_y);
       // make _pw_x, _pw_w multiple of 8
       _pw_w += _pw_x % 8;
       if (_pw_w % 8 > 0) _pw_w += 8 - _pw_w % 8;
@@ -336,6 +353,11 @@ class GxEPD2_3C : public Adafruit_GFX
     {
       epd2.writeImage(bitmap, x, y, w, h, invert, mirror_y, pgm);
     }
+    void writeImagePart(const uint8_t bitmap[], int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                        int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false)
+    {
+      epd2.writeImagePart(bitmap, x_part, y_part, w_bitmap, h_bitmap, x, y, w, h, invert, mirror_y, pgm);
+    }
     void writeImage(const uint8_t* black, const uint8_t* color, int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
     {
       epd2.writeImage(black, color, x, y, w, h, invert, mirror_y, pgm);
@@ -344,6 +366,16 @@ class GxEPD2_3C : public Adafruit_GFX
     {
       epd2.writeImage(black, color, x, y, w, h, false, false, false);
     }
+    void writeImagePart(const uint8_t* black, const uint8_t* color, int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                        int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
+    {
+      epd2.writeImagePart(black, color, x_part, y_part, w_bitmap, h_bitmap, x, y, w, h, invert, mirror_y, pgm);
+    }
+    void writeImagePart(const uint8_t* black, const uint8_t* color, int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                        int16_t x, int16_t y, int16_t w, int16_t h)
+    {
+      epd2.writeImagePart(black, color, x_part, y_part, w_bitmap, h_bitmap, x, y, w, h, false, false, false);
+    }
     // write sprite of native data to controller memory, without screen refresh; x and w should be multiple of 8
     void writeNative(const uint8_t* data1, const uint8_t* data2, int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
     {
@@ -354,6 +386,11 @@ class GxEPD2_3C : public Adafruit_GFX
     {
       epd2.drawImage(bitmap, x, y, w, h, invert, mirror_y, pgm);
     }
+    void drawImagePart(const uint8_t bitmap[], int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                        int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false)
+    {
+      epd2.drawImagePart(bitmap, x_part, y_part, w_bitmap, h_bitmap, x, y, w, h, invert, mirror_y, pgm);
+    }
     void drawImage(const uint8_t* black, const uint8_t* color, int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
     {
       epd2.drawImage(black, color, x, y, w, h, invert, mirror_y, pgm);
@@ -362,6 +399,16 @@ class GxEPD2_3C : public Adafruit_GFX
     {
       epd2.drawImage(black, color, x, y, w, h, false, false, false);
     }
+    void drawImagePart(const uint8_t* black, const uint8_t* color, int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                        int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
+    {
+      epd2.drawImagePart(black, color, x_part, y_part, w_bitmap, h_bitmap, x, y, w, h, invert, mirror_y, pgm);
+    }
+    void drawImagePart(const uint8_t* black, const uint8_t* color, int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                        int16_t x, int16_t y, int16_t w, int16_t h)
+    {
+      epd2.drawImagePart(black, color, x_part, y_part, w_bitmap, h_bitmap, x, y, w, h, false, false, false);
+    }
     // write sprite of native data to controller memory, with screen refresh; x and w should be multiple of 8
     void drawNative(const uint8_t* data1, const uint8_t* data2, int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
     {

src/GxEPD2_BW.h

@@ -144,8 +144,34 @@ class GxEPD2_BW : public Adafruit_GFX
     // display buffer content to screen, useful for full screen buffer
     void display(bool partial_update_mode = false)
     {
-      epd2.writeImage(_buffer, 0, 0, WIDTH, HEIGHT);
+      epd2.writeImage(_buffer, 0, 0, WIDTH, _page_height);
       epd2.refresh(partial_update_mode);
+      if (epd2.hasFastPartialUpdate)
+      {
+        epd2.writeImageAgain(_buffer, 0, 0, WIDTH, _page_height);
+      }
+    }
+
+    // display part of buffer content to screen, useful for full screen buffer
+    // displayWindow, use parameters according to actual rotation.
+    // x and w should be multiple of 8, for rotation 0 or 2,
+    // y and h should be multiple of 8, for rotation 1 or 3,
+    // else window is increased as needed,
+    // this is an addressing limitation of the e-paper controllers
+    void displayWindow(uint16_t x, uint16_t y, uint16_t w, uint16_t h)
+    {
+      x = gx_uint16_min(x, width());
+      y = gx_uint16_min(y, height());
+      w = gx_uint16_min(w, width() - x);
+      h = gx_uint16_min(h, height() - y);
+      _rotate(x, y, w, h);
+      uint16_t y_part = _reverse ? HEIGHT - h - y : y;
+      epd2.writeImagePart(_buffer, x, y_part, WIDTH, _page_height, x, y, w, h);
+      epd2.refresh(x, y, w, h);
+      if (epd2.hasFastPartialUpdate)
+      {
+        epd2.writeImagePartAgain(_buffer, x, y, WIDTH, _page_height, x, y, w, h);
+      }
     }
 
     void setFullWindow()
@@ -164,12 +190,12 @@ class GxEPD2_BW : public Adafruit_GFX
     // this is an addressing limitation of the e-paper controllers
     void setPartialWindow(uint16_t x, uint16_t y, uint16_t w, uint16_t h)
     {
-      _rotate(x, y, w, h);
+      _pw_x = gx_uint16_min(x, width());
+      _pw_y = gx_uint16_min(y, height());
+      _pw_w = gx_uint16_min(w, width() - _pw_x);
+      _pw_h = gx_uint16_min(h, height() - _pw_y);
+      _rotate(_pw_x, _pw_y, _pw_w, _pw_h);
       _using_partial_mode = true;
-      _pw_x = gx_uint16_min(x, WIDTH);
-      _pw_y = gx_uint16_min(y, HEIGHT);
-      _pw_w = gx_uint16_min(w, WIDTH - _pw_x);
-      _pw_h = gx_uint16_min(h, HEIGHT - _pw_y);
       // make _pw_x, _pw_w multiple of 8
       _pw_w += _pw_x % 8;
       if (_pw_w % 8 > 0) _pw_w += 8 - _pw_w % 8;
@@ -401,6 +427,11 @@ class GxEPD2_BW : public Adafruit_GFX
     {
       epd2.writeImage(bitmap, x, y, w, h, invert, mirror_y, pgm);
     }
+    void writeImagePart(const uint8_t bitmap[], int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                        int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false)
+    {
+      epd2.writeImagePart(bitmap, x_part, y_part, w_bitmap, h_bitmap, x, y, w, h, invert, mirror_y, pgm);
+    }
     void writeImage(const uint8_t* black, const uint8_t* color, int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
     {
       epd2.writeImage(black, color, x, y, w, h, invert, mirror_y, pgm);
@@ -409,6 +440,16 @@ class GxEPD2_BW : public Adafruit_GFX
     {
       epd2.writeImage(black, color, x, y, w, h, false, false, false);
     }
+    void writeImagePart(const uint8_t* black, const uint8_t* color, int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                        int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
+    {
+      epd2.writeImagePart(black, color, x_part, y_part, w_bitmap, h_bitmap, x, y, w, h, invert, mirror_y, pgm);
+    }
+    void writeImagePart(const uint8_t* black, const uint8_t* color, int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                        int16_t x, int16_t y, int16_t w, int16_t h)
+    {
+      epd2.writeImagePart(black, color, x_part, y_part, w_bitmap, h_bitmap, x, y, w, h, false, false, false);
+    }
     // write sprite of native data to controller memory, without screen refresh; x and w should be multiple of 8
     void writeNative(const uint8_t* data1, const uint8_t* data2, int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
     {
@@ -419,6 +460,11 @@ class GxEPD2_BW : public Adafruit_GFX
     {
       epd2.drawImage(bitmap, x, y, w, h, invert, mirror_y, pgm);
     }
+    void drawImagePart(const uint8_t bitmap[], int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                        int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false)
+    {
+      epd2.drawImagePart(bitmap, x_part, y_part, w_bitmap, h_bitmap, x, y, w, h, invert, mirror_y, pgm);
+    }
     void drawImage(const uint8_t* black, const uint8_t* color, int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
     {
       epd2.drawImage(black, color, x, y, w, h, invert, mirror_y, pgm);
@@ -427,6 +473,16 @@ class GxEPD2_BW : public Adafruit_GFX
     {
       epd2.drawImage(black, color, x, y, w, h, false, false, false);
     }
+    void drawImagePart(const uint8_t* black, const uint8_t* color, int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                        int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
+    {
+      epd2.drawImagePart(black, color, x_part, y_part, w_bitmap, h_bitmap, x, y, w, h, invert, mirror_y, pgm);
+    }
+    void drawImagePart(const uint8_t* black, const uint8_t* color, int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                        int16_t x, int16_t y, int16_t w, int16_t h)
+    {
+      epd2.drawImagePart(black, color, x_part, y_part, w_bitmap, h_bitmap, x, y, w, h, false, false, false);
+    }
     // write sprite of native data to controller memory, with screen refresh; x and w should be multiple of 8
     void drawNative(const uint8_t* data1, const uint8_t* data2, int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
     {

src/GxEPD2_EPD.h

@@ -37,7 +37,11 @@ class GxEPD2_EPD
     virtual void writeScreenBuffer(uint8_t value) = 0; // init controller memory (default white)
     // write to controller memory, without screen refresh; x and w should be multiple of 8
     virtual void writeImage(const uint8_t bitmap[], int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false) = 0;
+    virtual void writeImagePart(const uint8_t bitmap[], int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                                int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false) = 0;
     virtual void writeImage(const uint8_t* black, const uint8_t* color, int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false) = 0;
+    virtual void writeImagePart(const uint8_t* black, const uint8_t* color, int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                                int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false) = 0;
     // for differential update: set current and previous buffers equal (for fast partial update to work correctly)
     virtual void writeScreenBufferAgain(uint8_t value = 0xFF) // init controller memory (default white)
     {
@@ -49,9 +53,19 @@ class GxEPD2_EPD
       // most controllers with differential update do switch buffers on refresh, can use:
       writeImage(bitmap, x, y, w, h, invert, mirror_y, pgm);
     }
+    virtual void writeImagePartAgain(const uint8_t bitmap[], int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                                     int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false)
+    {
+      // most controllers with differential update do switch buffers on refresh, can use:
+      writeImagePart(bitmap, x_part, y_part, w_bitmap, h_bitmap, x, y, w, h, invert, mirror_y, pgm);
+    }
     // write to controller memory, with screen refresh; x and w should be multiple of 8
     virtual void drawImage(const uint8_t bitmap[], int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false) = 0;
+    virtual void drawImagePart(const uint8_t bitmap[], int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                                int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false) = 0;
     virtual void drawImage(const uint8_t* black, const uint8_t* color, int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false) = 0;
+    virtual void drawImagePart(const uint8_t* black, const uint8_t* color, int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                                int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false) = 0;
     virtual void refresh(bool partial_update_mode = false) = 0; // screen refresh from controller memory to full screen
     virtual void refresh(int16_t x, int16_t y, int16_t w, int16_t h) = 0; // screen refresh from controller memory, partial screen
     virtual void powerOff() = 0; // turns off generation of panel driving voltages, avoids screen fading over time

src/GxEPD2_GFX.h

@@ -46,12 +46,24 @@ class GxEPD2_GFX : public Adafruit_GFX
     virtual void writeScreenBuffer(uint8_t value = 0xFF) = 0; // init controller memory (default white)
     // write to controller memory, without screen refresh; x and w should be multiple of 8
     virtual void writeImage(const uint8_t bitmap[], int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false) = 0;
+    virtual void writeImagePart(const uint8_t bitmap[], int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                                int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false) = 0;
     virtual void writeImage(const uint8_t* black, const uint8_t* color, int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm) = 0;
     virtual void writeImage(const uint8_t* black, const uint8_t* color, int16_t x, int16_t y, int16_t w, int16_t h) = 0; // default options false
+    virtual void writeImagePart(const uint8_t* black, const uint8_t* color, int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                                int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm) = 0;
+    virtual void writeImagePart(const uint8_t* black, const uint8_t* color, int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                                int16_t x, int16_t y, int16_t w, int16_t h) = 0; // default options false
     // write to controller memory, with screen refresh; x and w should be multiple of 8
     virtual void drawImage(const uint8_t bitmap[], int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false) = 0;
+    virtual void drawImagePart(const uint8_t bitmap[], int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                                int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false) = 0;
     virtual void drawImage(const uint8_t* black, const uint8_t* color, int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm) = 0;
     virtual void drawImage(const uint8_t* black, const uint8_t* color, int16_t x, int16_t y, int16_t w, int16_t h) = 0; // default options false
+    virtual void drawImagePart(const uint8_t* black, const uint8_t* color, int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                                int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm) = 0;
+    virtual void drawImagePart(const uint8_t* black, const uint8_t* color, int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                                int16_t x, int16_t y, int16_t w, int16_t h) = 0; // default options false
     virtual void refresh(bool partial_update_mode = false) = 0; // screen refresh from controller memory to full screen
     virtual void refresh(int16_t x, int16_t y, int16_t w, int16_t h) = 0; // screen refresh from controller memory, partial screen
     virtual void powerOff() = 0; // turns off generation of panel driving voltages, avoids screen fading over time

src/epd/GxEPD2_154.cpp

@@ -107,7 +107,58 @@ void GxEPD2_154::writeImage(const uint8_t bitmap[], int16_t x, int16_t y, int16_
         data = bitmap[idx];
       }
       if (invert) data = ~data;
-      else _writeData(data);
+      _writeData(data);
+    }
+  }
+  delay(1); // yield() to avoid WDT on ESP8266 and ESP32
+}
+
+void GxEPD2_154::writeImagePart(const uint8_t bitmap[], int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                                int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
+{
+  delay(1); // yield() to avoid WDT on ESP8266 and ESP32
+  if ((w_bitmap < 0) || (h_bitmap < 0) || (w < 0) || (h < 0)) return;
+  if ((x_part < 0) || (x_part >= w_bitmap)) return;
+  if ((y_part < 0) || (y_part >= h_bitmap)) return;
+  int16_t wb_bitmap = (w_bitmap + 7) / 8; // width bytes, bitmaps are padded
+  x_part -= x_part % 8; // byte boundary
+  w = w_bitmap - x_part < w ? w_bitmap - x_part : w; // limit
+  h = h_bitmap - y_part < h ? h_bitmap - y_part : h; // limit
+  x -= x % 8; // byte boundary
+  w = 8 * ((w + 7) / 8); // byte boundary, bitmaps are padded
+  int16_t x1 = x < 0 ? 0 : x; // limit
+  int16_t y1 = y < 0 ? 0 : y; // limit
+  int16_t w1 = x + w < int16_t(WIDTH) ? w : int16_t(WIDTH) - x; // limit
+  int16_t h1 = y + h < int16_t(HEIGHT) ? h : int16_t(HEIGHT) - y; // limit
+  int16_t dx = x1 - x;
+  int16_t dy = y1 - y;
+  w1 -= dx;
+  h1 -= dy;
+  if ((w1 <= 0) || (h1 <= 0)) return;
+  if (!_using_partial_mode) _Init_Part();
+  _setPartialRamArea(x1, y1, w1, h1);
+  _writeCommand(0x24);
+  for (int16_t i = 0; i < h1; i++)
+  {
+    for (int16_t j = 0; j < w1 / 8; j++)
+    {
+      uint8_t data;
+      // use wb_bitmap, h_bitmap of bitmap for index!
+      int16_t idx = mirror_y ? x_part / 8 + j + dx / 8 + ((h_bitmap - 1 - (y_part + i + dy))) * wb_bitmap : x_part / 8 + j + dx / 8 + (y_part + i + dy) * wb_bitmap;
+      if (pgm)
+      {
+#if defined(__AVR) || defined(ESP8266) || defined(ESP32)
+        data = pgm_read_byte(&bitmap[idx]);
+#else
+        data = bitmap[idx];
+#endif
+      }
+      else
+      {
+        data = bitmap[idx];
+      }
+      if (invert) data = ~data;
+      _writeData(data);
     }
   }
   delay(1); // yield() to avoid WDT on ESP8266 and ESP32
@@ -121,6 +172,15 @@ void GxEPD2_154::writeImage(const uint8_t* black, const uint8_t* color, int16_t
   }
 }
 
+void GxEPD2_154::writeImagePart(const uint8_t* black, const uint8_t* color, int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                                int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
+{
+  if (black)
+  {
+    writeImagePart(black, x_part, y_part, w_bitmap, h_bitmap, x, y, w, h, invert, mirror_y, pgm);
+  }
+}
+
 void GxEPD2_154::writeNative(const uint8_t* data1, const uint8_t* data2, int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
 {
   if (data1)
@@ -133,18 +193,37 @@ void GxEPD2_154::drawImage(const uint8_t bitmap[], int16_t x, int16_t y, int16_t
 {
   writeImage(bitmap, x, y, w, h, invert, mirror_y, pgm);
   refresh(x, y, w, h);
+  writeImage(bitmap, x, y, w, h, invert, mirror_y, pgm);
+}
+
+void GxEPD2_154::drawImagePart(const uint8_t bitmap[], int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                               int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
+{
+  writeImagePart(bitmap, x_part, y_part, w_bitmap, h_bitmap, x, y, w, h, invert, mirror_y, pgm);
+  refresh(x, y, w, h);
+  writeImagePart(bitmap, x_part, y_part, w_bitmap, h_bitmap, x, y, w, h, invert, mirror_y, pgm);
 }
 
 void GxEPD2_154::drawImage(const uint8_t* black, const uint8_t* color, int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
 {
   writeImage(black, color, x, y, w, h, invert, mirror_y, pgm);
   refresh(x, y, w, h);
+  writeImage(black, color, x, y, w, h, invert, mirror_y, pgm);
+}
+
+void GxEPD2_154::drawImagePart(const uint8_t* black, const uint8_t* color, int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                               int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
+{
+  writeImagePart(black, color, x_part, y_part, w_bitmap, h_bitmap, x, y, w, h, invert, mirror_y, pgm);
+  refresh(x, y, w, h);
+  writeImagePart(black, color, x_part, y_part, w_bitmap, h_bitmap, x, y, w, h, invert, mirror_y, pgm);
 }
 
 void GxEPD2_154::drawNative(const uint8_t* data1, const uint8_t* data2, int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
 {
   writeNative(data1, data2, x, y, w, h, invert, mirror_y, pgm);
   refresh(x, y, w, h);
+  writeNative(data1, data2, x, y, w, h, invert, mirror_y, pgm);
 }
 
 void GxEPD2_154::refresh(bool partial_update_mode)

src/epd/GxEPD2_154.h

@@ -37,12 +37,20 @@ class GxEPD2_154 : public GxEPD2_EPD
     void writeScreenBuffer(uint8_t value = 0xFF); // init controller memory (default white)
     // write to controller memory, without screen refresh; x and w should be multiple of 8
     void writeImage(const uint8_t bitmap[], int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
+    void writeImagePart(const uint8_t bitmap[], int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                        int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     void writeImage(const uint8_t* black, const uint8_t* color, int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
+    void writeImagePart(const uint8_t* black, const uint8_t* color, int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                        int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     // write sprite of native data to controller memory, without screen refresh; x and w should be multiple of 8
     void writeNative(const uint8_t* data1, const uint8_t* data2, int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     // write to controller memory, with screen refresh; x and w should be multiple of 8
     void drawImage(const uint8_t bitmap[], int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
+    void drawImagePart(const uint8_t bitmap[], int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                       int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     void drawImage(const uint8_t* black, const uint8_t* color, int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
+    void drawImagePart(const uint8_t* black, const uint8_t* color, int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                       int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     // write sprite of native data to controller memory, with screen refresh; x and w should be multiple of 8
     void drawNative(const uint8_t* data1, const uint8_t* data2, int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     void refresh(bool partial_update_mode = false); // screen refresh from controller memory to full screen

src/epd/GxEPD2_213.cpp

@@ -107,7 +107,58 @@ void GxEPD2_213::writeImage(const uint8_t bitmap[], int16_t x, int16_t y, int16_
         data = bitmap[idx];
       }
       if (invert) data = ~data;
-      else _writeData(data);
+      _writeData(data);
+    }
+  }
+  delay(1); // yield() to avoid WDT on ESP8266 and ESP32
+}
+
+void GxEPD2_213::writeImagePart(const uint8_t bitmap[], int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                                int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
+{
+  delay(1); // yield() to avoid WDT on ESP8266 and ESP32
+  if ((w_bitmap < 0) || (h_bitmap < 0) || (w < 0) || (h < 0)) return;
+  if ((x_part < 0) || (x_part >= w_bitmap)) return;
+  if ((y_part < 0) || (y_part >= h_bitmap)) return;
+  int16_t wb_bitmap = (w_bitmap + 7) / 8; // width bytes, bitmaps are padded
+  x_part -= x_part % 8; // byte boundary
+  w = w_bitmap - x_part < w ? w_bitmap - x_part : w; // limit
+  h = h_bitmap - y_part < h ? h_bitmap - y_part : h; // limit
+  x -= x % 8; // byte boundary
+  w = 8 * ((w + 7) / 8); // byte boundary, bitmaps are padded
+  int16_t x1 = x < 0 ? 0 : x; // limit
+  int16_t y1 = y < 0 ? 0 : y; // limit
+  int16_t w1 = x + w < int16_t(WIDTH) ? w : int16_t(WIDTH) - x; // limit
+  int16_t h1 = y + h < int16_t(HEIGHT) ? h : int16_t(HEIGHT) - y; // limit
+  int16_t dx = x1 - x;
+  int16_t dy = y1 - y;
+  w1 -= dx;
+  h1 -= dy;
+  if ((w1 <= 0) || (h1 <= 0)) return;
+  if (!_using_partial_mode) _Init_Part();
+  _setPartialRamArea(x1, y1, w1, h1);
+  _writeCommand(0x24);
+  for (int16_t i = 0; i < h1; i++)
+  {
+    for (int16_t j = 0; j < w1 / 8; j++)
+    {
+      uint8_t data;
+      // use wb_bitmap, h_bitmap of bitmap for index!
+      int16_t idx = mirror_y ? x_part / 8 + j + dx / 8 + ((h_bitmap - 1 - (y_part + i + dy))) * wb_bitmap : x_part / 8 + j + dx / 8 + (y_part + i + dy) * wb_bitmap;
+      if (pgm)
+      {
+#if defined(__AVR) || defined(ESP8266) || defined(ESP32)
+        data = pgm_read_byte(&bitmap[idx]);
+#else
+        data = bitmap[idx];
+#endif
+      }
+      else
+      {
+        data = bitmap[idx];
+      }
+      if (invert) data = ~data;
+      _writeData(data);
     }
   }
   delay(1); // yield() to avoid WDT on ESP8266 and ESP32
@@ -121,6 +172,15 @@ void GxEPD2_213::writeImage(const uint8_t* black, const uint8_t* color, int16_t
   }
 }
 
+void GxEPD2_213::writeImagePart(const uint8_t* black, const uint8_t* color, int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                                int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
+{
+  if (black)
+  {
+    writeImagePart(black, x_part, y_part, w_bitmap, h_bitmap, x, y, w, h, invert, mirror_y, pgm);
+  }
+}
+
 void GxEPD2_213::writeNative(const uint8_t* data1, const uint8_t* data2, int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
 {
   if (data1)
@@ -133,18 +193,37 @@ void GxEPD2_213::drawImage(const uint8_t bitmap[], int16_t x, int16_t y, int16_t
 {
   writeImage(bitmap, x, y, w, h, invert, mirror_y, pgm);
   refresh(x, y, w, h);
+  writeImage(bitmap, x, y, w, h, invert, mirror_y, pgm);
+}
+
+void GxEPD2_213::drawImagePart(const uint8_t bitmap[], int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                               int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
+{
+  writeImagePart(bitmap, x_part, y_part, w_bitmap, h_bitmap, x, y, w, h, invert, mirror_y, pgm);
+  refresh(x, y, w, h);
+  writeImagePart(bitmap, x_part, y_part, w_bitmap, h_bitmap, x, y, w, h, invert, mirror_y, pgm);
 }
 
 void GxEPD2_213::drawImage(const uint8_t* black, const uint8_t* color, int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
 {
   writeImage(black, color, x, y, w, h, invert, mirror_y, pgm);
   refresh(x, y, w, h);
+  writeImage(black, color, x, y, w, h, invert, mirror_y, pgm);
+}
+
+void GxEPD2_213::drawImagePart(const uint8_t* black, const uint8_t* color, int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                               int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
+{
+  writeImagePart(black, color, x_part, y_part, w_bitmap, h_bitmap, x, y, w, h, invert, mirror_y, pgm);
+  refresh(x, y, w, h);
+  writeImagePart(black, color, x_part, y_part, w_bitmap, h_bitmap, x, y, w, h, invert, mirror_y, pgm);
 }
 
 void GxEPD2_213::drawNative(const uint8_t* data1, const uint8_t* data2, int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
 {
   writeNative(data1, data2, x, y, w, h, invert, mirror_y, pgm);
   refresh(x, y, w, h);
+  writeNative(data1, data2, x, y, w, h, invert, mirror_y, pgm);
 }
 
 void GxEPD2_213::refresh(bool partial_update_mode)

src/epd/GxEPD2_213.h

@@ -37,12 +37,20 @@ class GxEPD2_213 : public GxEPD2_EPD
     void writeScreenBuffer(uint8_t value = 0xFF); // init controller memory (default white)
     // write to controller memory, without screen refresh; x and w should be multiple of 8
     void writeImage(const uint8_t bitmap[], int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
+    void writeImagePart(const uint8_t bitmap[], int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                        int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     void writeImage(const uint8_t* black, const uint8_t* color, int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
+    void writeImagePart(const uint8_t* black, const uint8_t* color, int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                        int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     // write sprite of native data to controller memory, without screen refresh; x and w should be multiple of 8
     void writeNative(const uint8_t* data1, const uint8_t* data2, int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     // write to controller memory, with screen refresh; x and w should be multiple of 8
     void drawImage(const uint8_t bitmap[], int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
+    void drawImagePart(const uint8_t bitmap[], int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                       int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     void drawImage(const uint8_t* black, const uint8_t* color, int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
+    void drawImagePart(const uint8_t* black, const uint8_t* color, int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                       int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     // write sprite of native data to controller memory, with screen refresh; x and w should be multiple of 8
     void drawNative(const uint8_t* data1, const uint8_t* data2, int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     void refresh(bool partial_update_mode = false); // screen refresh from controller memory to full screen

src/epd/GxEPD2_213_B72.cpp

@@ -126,7 +126,70 @@ void GxEPD2_213_B72::_writeImage(uint8_t command, const uint8_t bitmap[], int16_
         data = bitmap[idx];
       }
       if (invert) data = ~data;
-      else _writeData(data);
+      _writeData(data);
+    }
+  }
+  delay(1); // yield() to avoid WDT on ESP8266 and ESP32
+}
+
+void GxEPD2_213_B72::writeImagePart(const uint8_t bitmap[], int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                                    int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
+{
+  _writeImagePart(0x24, bitmap, x_part, y_part, w_bitmap, h_bitmap, x, y, w, h, invert, mirror_y, pgm);
+}
+
+void GxEPD2_213_B72::writeImagePartAgain(const uint8_t bitmap[], int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+    int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
+{
+  _writeImagePart(0x26, bitmap, x_part, y_part, w_bitmap, h_bitmap, x, y, w, h, invert, mirror_y, pgm);
+}
+
+void GxEPD2_213_B72::_writeImagePart(uint8_t command, const uint8_t bitmap[], int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                                     int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
+{
+  delay(1); // yield() to avoid WDT on ESP8266 and ESP32
+  if ((w_bitmap < 0) || (h_bitmap < 0) || (w < 0) || (h < 0)) return;
+  if ((x_part < 0) || (x_part >= w_bitmap)) return;
+  if ((y_part < 0) || (y_part >= h_bitmap)) return;
+  int16_t wb_bitmap = (w_bitmap + 7) / 8; // width bytes, bitmaps are padded
+  x_part -= x_part % 8; // byte boundary
+  w = w_bitmap - x_part < w ? w_bitmap - x_part : w; // limit
+  h = h_bitmap - y_part < h ? h_bitmap - y_part : h; // limit
+  x -= x % 8; // byte boundary
+  w = 8 * ((w + 7) / 8); // byte boundary, bitmaps are padded
+  int16_t x1 = x < 0 ? 0 : x; // limit
+  int16_t y1 = y < 0 ? 0 : y; // limit
+  int16_t w1 = x + w < int16_t(WIDTH) ? w : int16_t(WIDTH) - x; // limit
+  int16_t h1 = y + h < int16_t(HEIGHT) ? h : int16_t(HEIGHT) - y; // limit
+  int16_t dx = x1 - x;
+  int16_t dy = y1 - y;
+  w1 -= dx;
+  h1 -= dy;
+  if ((w1 <= 0) || (h1 <= 0)) return;
+  if (!_using_partial_mode) _Init_Part();
+  _setPartialRamArea(x1, y1, w1, h1);
+  _writeCommand(command);
+  for (int16_t i = 0; i < h1; i++)
+  {
+    for (int16_t j = 0; j < w1 / 8; j++)
+    {
+      uint8_t data;
+      // use wb_bitmap, h_bitmap of bitmap for index!
+      int16_t idx = mirror_y ? x_part / 8 + j + dx / 8 + ((h_bitmap - 1 - (y_part + i + dy))) * wb_bitmap : x_part / 8 + j + dx / 8 + (y_part + i + dy) * wb_bitmap;
+      if (pgm)
+      {
+#if defined(__AVR) || defined(ESP8266) || defined(ESP32)
+        data = pgm_read_byte(&bitmap[idx]);
+#else
+        data = bitmap[idx];
+#endif
+      }
+      else
+      {
+        data = bitmap[idx];
+      }
+      if (invert) data = ~data;
+      _writeData(data);
     }
   }
   delay(1); // yield() to avoid WDT on ESP8266 and ESP32
@@ -140,6 +203,15 @@ void GxEPD2_213_B72::writeImage(const uint8_t* black, const uint8_t* color, int1
   }
 }
 
+void GxEPD2_213_B72::writeImagePart(const uint8_t* black, const uint8_t* color, int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                                    int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
+{
+  if (black)
+  {
+    writeImagePart(black, x_part, y_part, w_bitmap, h_bitmap, x, y, w, h, invert, mirror_y, pgm);
+  }
+}
+
 void GxEPD2_213_B72::writeNative(const uint8_t* data1, const uint8_t* data2, int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
 {
   if (data1)
@@ -155,6 +227,14 @@ void GxEPD2_213_B72::drawImage(const uint8_t bitmap[], int16_t x, int16_t y, int
   writeImageAgain(bitmap, x, y, w, h, invert, mirror_y, pgm);
 }
 
+void GxEPD2_213_B72::drawImagePart(const uint8_t bitmap[], int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                                   int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
+{
+  writeImagePart(bitmap, x_part, y_part, w_bitmap, h_bitmap, x, y, w, h, invert, mirror_y, pgm);
+  refresh(x, y, w, h);
+  writeImagePartAgain(bitmap, x_part, y_part, w_bitmap, h_bitmap, x, y, w, h, invert, mirror_y, pgm);
+}
+
 void GxEPD2_213_B72::drawImage(const uint8_t* black, const uint8_t* color, int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
 {
   if (black)
@@ -163,6 +243,15 @@ void GxEPD2_213_B72::drawImage(const uint8_t* black, const uint8_t* color, int16
   }
 }
 
+void GxEPD2_213_B72::drawImagePart(const uint8_t* black, const uint8_t* color, int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                                   int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
+{
+  if (black)
+  {
+    drawImagePart(black, x_part, y_part, w_bitmap, h_bitmap, x, y, w, h, invert, mirror_y, pgm);
+  }
+}
+
 void GxEPD2_213_B72::drawNative(const uint8_t* data1, const uint8_t* data2, int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
 {
   if (data1)

src/epd/GxEPD2_213_B72.h

@@ -38,14 +38,24 @@ class GxEPD2_213_B72 : public GxEPD2_EPD
     void writeScreenBufferAgain(uint8_t value = 0xFF); // init previous buffer controller memory (default white)
     // write to controller memory, without screen refresh; x and w should be multiple of 8
     void writeImage(const uint8_t bitmap[], int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
+    void writeImagePart(const uint8_t bitmap[], int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                        int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     void writeImage(const uint8_t* black, const uint8_t* color, int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
+    void writeImagePart(const uint8_t* black, const uint8_t* color, int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                        int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     // for differential update: set current and previous buffers equal (for fast partial update to work correctly)
     void writeImageAgain(const uint8_t bitmap[], int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
+    void writeImagePartAgain(const uint8_t bitmap[], int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                             int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     // write sprite of native data to controller memory, without screen refresh; x and w should be multiple of 8
     void writeNative(const uint8_t* data1, const uint8_t* data2, int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     // write to controller memory, with screen refresh; x and w should be multiple of 8
     void drawImage(const uint8_t bitmap[], int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
+    void drawImagePart(const uint8_t bitmap[], int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                       int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     void drawImage(const uint8_t* black, const uint8_t* color, int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
+    void drawImagePart(const uint8_t* black, const uint8_t* color, int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                       int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     // write sprite of native data to controller memory, with screen refresh; x and w should be multiple of 8
     void drawNative(const uint8_t* data1, const uint8_t* data2, int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     void refresh(bool partial_update_mode = false); // screen refresh from controller memory to full screen
@@ -54,6 +64,8 @@ class GxEPD2_213_B72 : public GxEPD2_EPD
     void hibernate(); // turns powerOff() and sets controller to deep sleep for minimum power use, ONLY if wakeable by RST (rst >= 0)
   private:
     void _writeImage(uint8_t command, const uint8_t bitmap[], int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
+    void _writeImagePart(uint8_t command, const uint8_t bitmap[], int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                         int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     void _writeScreenBuffer(uint8_t value);
     void _setPartialRamArea(uint16_t x, uint16_t y, uint16_t w, uint16_t h);
     void _PowerOn();

src/epd/GxEPD2_213_flex.cpp

@@ -120,6 +120,59 @@ void GxEPD2_213_flex::writeImage(const uint8_t bitmap[], int16_t x, int16_t y, i
   delay(1); // yield() to avoid WDT on ESP8266 and ESP32
 }
 
+void GxEPD2_213_flex::writeImagePart(const uint8_t bitmap[], int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                                     int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
+{
+  delay(1); // yield() to avoid WDT on ESP8266 and ESP32
+  if ((w_bitmap < 0) || (h_bitmap < 0) || (w < 0) || (h < 0)) return;
+  if ((x_part < 0) || (x_part >= w_bitmap)) return;
+  if ((y_part < 0) || (y_part >= h_bitmap)) return;
+  int16_t wb_bitmap = (w_bitmap + 7) / 8; // width bytes, bitmaps are padded
+  x_part -= x_part % 8; // byte boundary
+  w = w_bitmap - x_part < w ? w_bitmap - x_part : w; // limit
+  h = h_bitmap - y_part < h ? h_bitmap - y_part : h; // limit
+  x -= x % 8; // byte boundary
+  w = 8 * ((w + 7) / 8); // byte boundary, bitmaps are padded
+  int16_t x1 = x < 0 ? 0 : x; // limit
+  int16_t y1 = y < 0 ? 0 : y; // limit
+  int16_t w1 = x + w < int16_t(WIDTH) ? w : int16_t(WIDTH) - x; // limit
+  int16_t h1 = y + h < int16_t(HEIGHT) ? h : int16_t(HEIGHT) - y; // limit
+  int16_t dx = x1 - x;
+  int16_t dy = y1 - y;
+  w1 -= dx;
+  h1 -= dy;
+  if ((w1 <= 0) || (h1 <= 0)) return;
+  if (!_using_partial_mode) _Init_Part();
+  _writeCommand(0x91); // partial in
+  _setPartialRamArea(x1, y1, w1, h1);
+  _writeCommand(0x13);
+  for (int16_t i = 0; i < h1; i++)
+  {
+    for (int16_t j = 0; j < w1 / 8; j++)
+    {
+      uint8_t data;
+      // use wb_bitmap, h_bitmap of bitmap for index!
+      int16_t idx = mirror_y ? x_part / 8 + j + dx / 8 + ((h_bitmap - 1 - (y_part + i + dy))) * wb_bitmap : x_part / 8 + j + dx / 8 + (y_part + i + dy) * wb_bitmap;
+      if (pgm)
+      {
+#if defined(__AVR) || defined(ESP8266) || defined(ESP32)
+        data = pgm_read_byte(&bitmap[idx]);
+#else
+        data = bitmap[idx];
+#endif
+      }
+      else
+      {
+        data = bitmap[idx];
+      }
+      if (invert) data = ~data;
+      _writeData(data);
+    }
+  }
+  _writeCommand(0x92); // partial out
+  delay(1); // yield() to avoid WDT on ESP8266 and ESP32
+}
+
 void GxEPD2_213_flex::writeImage(const uint8_t* black, const uint8_t* color, int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
 {
   if (black)
@@ -128,6 +181,15 @@ void GxEPD2_213_flex::writeImage(const uint8_t* black, const uint8_t* color, int
   }
 }
 
+void GxEPD2_213_flex::writeImagePart(const uint8_t* black, const uint8_t* color, int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                                     int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
+{
+  if (black)
+  {
+    writeImagePart(black, x_part, y_part, w_bitmap, h_bitmap, x, y, w, h, invert, mirror_y, pgm);
+  }
+}
+
 void GxEPD2_213_flex::writeNative(const uint8_t* data1, const uint8_t* data2, int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
 {
   if (data1)
@@ -140,18 +202,37 @@ void GxEPD2_213_flex::drawImage(const uint8_t bitmap[], int16_t x, int16_t y, in
 {
   writeImage(bitmap, x, y, w, h, invert, mirror_y, pgm);
   refresh(x, y, w, h);
+  writeImage(bitmap, x, y, w, h, invert, mirror_y, pgm);
+}
+
+void GxEPD2_213_flex::drawImagePart(const uint8_t bitmap[], int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                                    int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
+{
+  writeImagePart(bitmap, x_part, y_part, w_bitmap, h_bitmap, x, y, w, h, invert, mirror_y, pgm);
+  refresh(x, y, w, h);
+  writeImagePart(bitmap, x_part, y_part, w_bitmap, h_bitmap, x, y, w, h, invert, mirror_y, pgm);
 }
 
 void GxEPD2_213_flex::drawImage(const uint8_t* black, const uint8_t* color, int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
 {
   writeImage(black, color, x, y, w, h, invert, mirror_y, pgm);
   refresh(x, y, w, h);
+  writeImage(black, color, x, y, w, h, invert, mirror_y, pgm);
+}
+
+void GxEPD2_213_flex::drawImagePart(const uint8_t* black, const uint8_t* color, int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                                    int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
+{
+  writeImagePart(black, color, x_part, y_part, w_bitmap, h_bitmap, x, y, w, h, invert, mirror_y, pgm);
+  refresh(x, y, w, h);
+  writeImagePart(black, color, x_part, y_part, w_bitmap, h_bitmap, x, y, w, h, invert, mirror_y, pgm);
 }
 
 void GxEPD2_213_flex::drawNative(const uint8_t* data1, const uint8_t* data2, int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
 {
   writeNative(data1, data2, x, y, w, h, invert, mirror_y, pgm);
   refresh(x, y, w, h);
+  writeNative(data1, data2, x, y, w, h, invert, mirror_y, pgm);
 }
 
 void GxEPD2_213_flex::refresh(bool partial_update_mode)

src/epd/GxEPD2_213_flex.h

@@ -37,12 +37,20 @@ class GxEPD2_213_flex : public GxEPD2_EPD
     void writeScreenBuffer(uint8_t value = 0xFF); // init controller memory (default white)
     // write to controller memory, without screen refresh; x and w should be multiple of 8
     void writeImage(const uint8_t bitmap[], int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
+    void writeImagePart(const uint8_t bitmap[], int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                        int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     void writeImage(const uint8_t* black, const uint8_t* color, int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
+    void writeImagePart(const uint8_t* black, const uint8_t* color, int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                        int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     // write sprite of native data to controller memory, without screen refresh; x and w should be multiple of 8
     void writeNative(const uint8_t* data1, const uint8_t* data2, int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     // write to controller memory, with screen refresh; x and w should be multiple of 8
     void drawImage(const uint8_t bitmap[], int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
+    void drawImagePart(const uint8_t bitmap[], int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                       int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     void drawImage(const uint8_t* black, const uint8_t* color, int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
+    void drawImagePart(const uint8_t* black, const uint8_t* color, int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                       int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     // write sprite of native data to controller memory, with screen refresh; x and w should be multiple of 8
     void drawNative(const uint8_t* data1, const uint8_t* data2, int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     void refresh(bool partial_update_mode = false); // screen refresh from controller memory to full screen

src/epd/GxEPD2_270.cpp

@@ -123,7 +123,69 @@ void GxEPD2_270::_writeImage(uint8_t command, const uint8_t bitmap[], int16_t x,
         data = bitmap[idx];
       }
       if (invert) data = ~data;
-      else _writeData(data);
+      _writeData(data);
+    }
+  }
+  delay(1); // yield() to avoid WDT on ESP8266 and ESP32
+}
+
+void GxEPD2_270::writeImagePart(const uint8_t bitmap[], int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                                    int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
+{
+  _writeImagePart(0x15, bitmap, x_part, y_part, w_bitmap, h_bitmap, x, y, w, h, invert, mirror_y, pgm);
+}
+
+void GxEPD2_270::writeImagePartAgain(const uint8_t bitmap[], int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+    int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
+{
+  _writeImagePart(0x14, bitmap, x_part, y_part, w_bitmap, h_bitmap, x, y, w, h, invert, mirror_y, pgm);
+}
+
+void GxEPD2_270::_writeImagePart(uint8_t command, const uint8_t bitmap[], int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                                int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
+{
+  delay(1); // yield() to avoid WDT on ESP8266 and ESP32
+  if ((w_bitmap < 0) || (h_bitmap < 0) || (w < 0) || (h < 0)) return;
+  if ((x_part < 0) || (x_part >= w_bitmap)) return;
+  if ((y_part < 0) || (y_part >= h_bitmap)) return;
+  int16_t wb_bitmap = (w_bitmap + 7) / 8; // width bytes, bitmaps are padded
+  x_part -= x_part % 8; // byte boundary
+  w = w_bitmap - x_part < w ? w_bitmap - x_part : w; // limit
+  h = h_bitmap - y_part < h ? h_bitmap - y_part : h; // limit
+  x -= x % 8; // byte boundary
+  w = 8 * ((w + 7) / 8); // byte boundary, bitmaps are padded
+  int16_t x1 = x < 0 ? 0 : x; // limit
+  int16_t y1 = y < 0 ? 0 : y; // limit
+  int16_t w1 = x + w < int16_t(WIDTH) ? w : int16_t(WIDTH) - x; // limit
+  int16_t h1 = y + h < int16_t(HEIGHT) ? h : int16_t(HEIGHT) - y; // limit
+  int16_t dx = x1 - x;
+  int16_t dy = y1 - y;
+  w1 -= dx;
+  h1 -= dy;
+  if ((w1 <= 0) || (h1 <= 0)) return;
+  if (!_using_partial_mode) _Init_Part();
+  _setPartialRamArea(command, x1, y1, w1, h1);
+  for (int16_t i = 0; i < h1; i++)
+  {
+    for (int16_t j = 0; j < w1 / 8; j++)
+    {
+      uint8_t data;
+      // use wb_bitmap, h_bitmap of bitmap for index!
+      int16_t idx = mirror_y ? x_part / 8 + j + dx / 8 + ((h_bitmap - 1 - (y_part + i + dy))) * wb_bitmap : x_part / 8 + j + dx / 8 + (y_part + i + dy) * wb_bitmap;
+      if (pgm)
+      {
+#if defined(__AVR) || defined(ESP8266) || defined(ESP32)
+        data = pgm_read_byte(&bitmap[idx]);
+#else
+        data = bitmap[idx];
+#endif
+      }
+      else
+      {
+        data = bitmap[idx];
+      }
+      if (invert) data = ~data;
+      _writeData(data);
     }
   }
   delay(1); // yield() to avoid WDT on ESP8266 and ESP32
@@ -137,6 +199,15 @@ void GxEPD2_270::writeImage(const uint8_t* black, const uint8_t* color, int16_t
   }
 }
 
+void GxEPD2_270::writeImagePart(const uint8_t* black, const uint8_t* color, int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                                int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
+{
+  if (black)
+  {
+    writeImagePart(black, x_part, y_part, w_bitmap, h_bitmap, x, y, w, h, invert, mirror_y, pgm);
+  }
+}
+
 void GxEPD2_270::writeNative(const uint8_t* data1, const uint8_t* data2, int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
 {
   if (data1)
@@ -152,6 +223,14 @@ void GxEPD2_270::drawImage(const uint8_t bitmap[], int16_t x, int16_t y, int16_t
   writeImageAgain(bitmap, x, y, w, h, invert, mirror_y, pgm);
 }
 
+void GxEPD2_270::drawImagePart(const uint8_t bitmap[], int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                               int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
+{
+  writeImagePart(bitmap, x_part, y_part, w_bitmap, h_bitmap, x, y, w, h, invert, mirror_y, pgm);
+  refresh(x, y, w, h);
+  writeImagePartAgain(bitmap, x_part, y_part, w_bitmap, h_bitmap, x, y, w, h, invert, mirror_y, pgm);
+}
+
 void GxEPD2_270::drawImage(const uint8_t* black, const uint8_t* color, int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
 {
   if (black)
@@ -160,6 +239,15 @@ void GxEPD2_270::drawImage(const uint8_t* black, const uint8_t* color, int16_t x
   }
 }
 
+void GxEPD2_270::drawImagePart(const uint8_t* black, const uint8_t* color, int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                               int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
+{
+  if (black)
+  {
+    drawImagePart(black, x_part, y_part, w_bitmap, h_bitmap, x, y, w, h, invert, mirror_y, pgm);
+  }
+}
+
 void GxEPD2_270::drawNative(const uint8_t* data1, const uint8_t* data2, int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
 {
   if (data1)

src/epd/GxEPD2_270.h

@@ -38,14 +38,24 @@ class GxEPD2_270 : public GxEPD2_EPD
     void writeScreenBufferAgain(uint8_t value = 0xFF); // init previous buffer controller memory (default white)
     // write to controller memory, without screen refresh; x and w should be multiple of 8
     void writeImage(const uint8_t bitmap[], int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
+    void writeImagePart(const uint8_t bitmap[], int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                        int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     void writeImage(const uint8_t* black, const uint8_t* color, int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
+    void writeImagePart(const uint8_t* black, const uint8_t* color, int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                        int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     // for differential update: set current and previous buffers equal (for fast partial update to work correctly)
     void writeImageAgain(const uint8_t bitmap[], int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
+    void writeImagePartAgain(const uint8_t bitmap[], int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                             int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     // write sprite of native data to controller memory, without screen refresh; x and w should be multiple of 8
     void writeNative(const uint8_t* data1, const uint8_t* data2, int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     // write to controller memory, with screen refresh; x and w should be multiple of 8
     void drawImage(const uint8_t bitmap[], int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
+    void drawImagePart(const uint8_t bitmap[], int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                       int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     void drawImage(const uint8_t* black, const uint8_t* color, int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
+    void drawImagePart(const uint8_t* black, const uint8_t* color, int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                       int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     // write sprite of native data to controller memory, with screen refresh; x and w should be multiple of 8
     void drawNative(const uint8_t* data1, const uint8_t* data2, int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     void refresh(bool partial_update_mode = false); // screen refresh from controller memory to full screen
@@ -54,6 +64,8 @@ class GxEPD2_270 : public GxEPD2_EPD
     void hibernate(); // turns powerOff() and sets controller to deep sleep for minimum power use, ONLY if wakeable by RST (rst >= 0)
   private:
     void _writeImage(uint8_t command, const uint8_t bitmap[], int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
+    void _writeImagePart(uint8_t command, const uint8_t bitmap[], int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                         int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     void _writeScreenBuffer(uint8_t value);
     void _setPartialRamArea(uint8_t command, uint16_t x, uint16_t y, uint16_t w, uint16_t h);
     void _refreshWindow(uint16_t x, uint16_t y, uint16_t w, uint16_t h);

src/epd/GxEPD2_290.cpp

@@ -107,7 +107,58 @@ void GxEPD2_290::writeImage(const uint8_t bitmap[], int16_t x, int16_t y, int16_
         data = bitmap[idx];
       }
       if (invert) data = ~data;
-      else _writeData(data);
+      _writeData(data);
+    }
+  }
+  delay(1); // yield() to avoid WDT on ESP8266 and ESP32
+}
+
+void GxEPD2_290::writeImagePart(const uint8_t bitmap[], int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                                int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
+{
+  delay(1); // yield() to avoid WDT on ESP8266 and ESP32
+  if ((w_bitmap < 0) || (h_bitmap < 0) || (w < 0) || (h < 0)) return;
+  if ((x_part < 0) || (x_part >= w_bitmap)) return;
+  if ((y_part < 0) || (y_part >= h_bitmap)) return;
+  int16_t wb_bitmap = (w_bitmap + 7) / 8; // width bytes, bitmaps are padded
+  x_part -= x_part % 8; // byte boundary
+  w = w_bitmap - x_part < w ? w_bitmap - x_part : w; // limit
+  h = h_bitmap - y_part < h ? h_bitmap - y_part : h; // limit
+  x -= x % 8; // byte boundary
+  w = 8 * ((w + 7) / 8); // byte boundary, bitmaps are padded
+  int16_t x1 = x < 0 ? 0 : x; // limit
+  int16_t y1 = y < 0 ? 0 : y; // limit
+  int16_t w1 = x + w < int16_t(WIDTH) ? w : int16_t(WIDTH) - x; // limit
+  int16_t h1 = y + h < int16_t(HEIGHT) ? h : int16_t(HEIGHT) - y; // limit
+  int16_t dx = x1 - x;
+  int16_t dy = y1 - y;
+  w1 -= dx;
+  h1 -= dy;
+  if ((w1 <= 0) || (h1 <= 0)) return;
+  if (!_using_partial_mode) _Init_Part();
+  _setPartialRamArea(x1, y1, w1, h1);
+  _writeCommand(0x24);
+  for (int16_t i = 0; i < h1; i++)
+  {
+    for (int16_t j = 0; j < w1 / 8; j++)
+    {
+      uint8_t data;
+      // use wb_bitmap, h_bitmap of bitmap for index!
+      int16_t idx = mirror_y ? x_part / 8 + j + dx / 8 + ((h_bitmap - 1 - (y_part + i + dy))) * wb_bitmap : x_part / 8 + j + dx / 8 + (y_part + i + dy) * wb_bitmap;
+      if (pgm)
+      {
+#if defined(__AVR) || defined(ESP8266) || defined(ESP32)
+        data = pgm_read_byte(&bitmap[idx]);
+#else
+        data = bitmap[idx];
+#endif
+      }
+      else
+      {
+        data = bitmap[idx];
+      }
+      if (invert) data = ~data;
+      _writeData(data);
     }
   }
   delay(1); // yield() to avoid WDT on ESP8266 and ESP32
@@ -121,6 +172,15 @@ void GxEPD2_290::writeImage(const uint8_t* black, const uint8_t* color, int16_t
   }
 }
 
+void GxEPD2_290::writeImagePart(const uint8_t* black, const uint8_t* color, int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                                int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
+{
+  if (black)
+  {
+    writeImagePart(black, x_part, y_part, w_bitmap, h_bitmap, x, y, w, h, invert, mirror_y, pgm);
+  }
+}
+
 void GxEPD2_290::writeNative(const uint8_t* data1, const uint8_t* data2, int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
 {
   if (data1)
@@ -133,18 +193,37 @@ void GxEPD2_290::drawImage(const uint8_t bitmap[], int16_t x, int16_t y, int16_t
 {
   writeImage(bitmap, x, y, w, h, invert, mirror_y, pgm);
   refresh(x, y, w, h);
+  writeImage(bitmap, x, y, w, h, invert, mirror_y, pgm);
+}
+
+void GxEPD2_290::drawImagePart(const uint8_t bitmap[], int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                               int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
+{
+  writeImagePart(bitmap, x_part, y_part, w_bitmap, h_bitmap, x, y, w, h, invert, mirror_y, pgm);
+  refresh(x, y, w, h);
+  writeImagePart(bitmap, x_part, y_part, w_bitmap, h_bitmap, x, y, w, h, invert, mirror_y, pgm);
 }
 
 void GxEPD2_290::drawImage(const uint8_t* black, const uint8_t* color, int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
 {
   writeImage(black, color, x, y, w, h, invert, mirror_y, pgm);
   refresh(x, y, w, h);
+  writeImage(black, color, x, y, w, h, invert, mirror_y, pgm);
 }
 
 void GxEPD2_290::drawNative(const uint8_t* data1, const uint8_t* data2, int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
 {
   writeNative(data1, data2, x, y, w, h, invert, mirror_y, pgm);
   refresh(x, y, w, h);
+  writeNative(data1, data2, x, y, w, h, invert, mirror_y, pgm);
+}
+
+void GxEPD2_290::drawImagePart(const uint8_t* black, const uint8_t* color, int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                               int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
+{
+  writeImagePart(black, color, x_part, y_part, w_bitmap, h_bitmap, x, y, w, h, invert, mirror_y, pgm);
+  refresh(x, y, w, h);
+  writeImagePart(black, color, x_part, y_part, w_bitmap, h_bitmap, x, y, w, h, invert, mirror_y, pgm);
 }
 
 void GxEPD2_290::refresh(bool partial_update_mode)

src/epd/GxEPD2_290.h

@@ -37,12 +37,20 @@ class GxEPD2_290 : public GxEPD2_EPD
     void writeScreenBuffer(uint8_t value = 0xFF); // init controller memory (default white)
     // write to controller memory, without screen refresh; x and w should be multiple of 8
     void writeImage(const uint8_t bitmap[], int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
+    void writeImagePart(const uint8_t bitmap[], int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                        int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     void writeImage(const uint8_t* black, const uint8_t* color, int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
+    void writeImagePart(const uint8_t* black, const uint8_t* color, int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                        int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     // write sprite of native data to controller memory, without screen refresh; x and w should be multiple of 8
     void writeNative(const uint8_t* data1, const uint8_t* data2, int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     // write to controller memory, with screen refresh; x and w should be multiple of 8
     void drawImage(const uint8_t bitmap[], int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
+    void drawImagePart(const uint8_t bitmap[], int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                       int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     void drawImage(const uint8_t* black, const uint8_t* color, int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
+    void drawImagePart(const uint8_t* black, const uint8_t* color, int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                       int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     // write sprite of native data to controller memory, with screen refresh; x and w should be multiple of 8
     void drawNative(const uint8_t* data1, const uint8_t* data2, int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     void refresh(bool partial_update_mode = false); // screen refresh from controller memory to full screen

src/epd/GxEPD2_290_T5.cpp

@@ -120,6 +120,59 @@ void GxEPD2_290_T5::writeImage(const uint8_t bitmap[], int16_t x, int16_t y, int
   delay(1); // yield() to avoid WDT on ESP8266 and ESP32
 }
 
+void GxEPD2_290_T5::writeImagePart(const uint8_t bitmap[], int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                                int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
+{
+  delay(1); // yield() to avoid WDT on ESP8266 and ESP32
+  if ((w_bitmap < 0) || (h_bitmap < 0) || (w < 0) || (h < 0)) return;
+  if ((x_part < 0) || (x_part >= w_bitmap)) return;
+  if ((y_part < 0) || (y_part >= h_bitmap)) return;
+  int16_t wb_bitmap = (w_bitmap + 7) / 8; // width bytes, bitmaps are padded
+  x_part -= x_part % 8; // byte boundary
+  w = w_bitmap - x_part < w ? w_bitmap - x_part : w; // limit
+  h = h_bitmap - y_part < h ? h_bitmap - y_part : h; // limit
+  x -= x % 8; // byte boundary
+  w = 8 * ((w + 7) / 8); // byte boundary, bitmaps are padded
+  int16_t x1 = x < 0 ? 0 : x; // limit
+  int16_t y1 = y < 0 ? 0 : y; // limit
+  int16_t w1 = x + w < int16_t(WIDTH) ? w : int16_t(WIDTH) - x; // limit
+  int16_t h1 = y + h < int16_t(HEIGHT) ? h : int16_t(HEIGHT) - y; // limit
+  int16_t dx = x1 - x;
+  int16_t dy = y1 - y;
+  w1 -= dx;
+  h1 -= dy;
+  if ((w1 <= 0) || (h1 <= 0)) return;
+  if (!_using_partial_mode) _Init_Part();
+  _writeCommand(0x91); // partial in
+  _setPartialRamArea(x1, y1, w1, h1);
+  _writeCommand(0x13);
+  for (int16_t i = 0; i < h1; i++)
+  {
+    for (int16_t j = 0; j < w1 / 8; j++)
+    {
+      uint8_t data;
+      // use wb_bitmap, h_bitmap of bitmap for index!
+      int16_t idx = mirror_y ? x_part / 8 + j + dx / 8 + ((h_bitmap - 1 - (y_part + i + dy))) * wb_bitmap : x_part / 8 + j + dx / 8 + (y_part + i + dy) * wb_bitmap;
+      if (pgm)
+      {
+#if defined(__AVR) || defined(ESP8266) || defined(ESP32)
+        data = pgm_read_byte(&bitmap[idx]);
+#else
+        data = bitmap[idx];
+#endif
+      }
+      else
+      {
+        data = bitmap[idx];
+      }
+      if (invert) data = ~data;
+      _writeData(data);
+    }
+  }
+  _writeCommand(0x92); // partial out
+  delay(1); // yield() to avoid WDT on ESP8266 and ESP32
+}
+
 void GxEPD2_290_T5::writeImage(const uint8_t* black, const uint8_t* color, int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
 {
   if (black)
@@ -128,6 +181,15 @@ void GxEPD2_290_T5::writeImage(const uint8_t* black, const uint8_t* color, int16
   }
 }
 
+void GxEPD2_290_T5::writeImagePart(const uint8_t* black, const uint8_t* color, int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                                int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
+{
+  if (black)
+  {
+    writeImagePart(black, x_part, y_part, w_bitmap, h_bitmap, x, y, w, h, invert, mirror_y, pgm);
+  }
+}
+
 void GxEPD2_290_T5::writeNative(const uint8_t* data1, const uint8_t* data2, int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
 {
   if (data1)
@@ -140,18 +202,37 @@ void GxEPD2_290_T5::drawImage(const uint8_t bitmap[], int16_t x, int16_t y, int1
 {
   writeImage(bitmap, x, y, w, h, invert, mirror_y, pgm);
   refresh(x, y, w, h);
+  writeImage(bitmap, x, y, w, h, invert, mirror_y, pgm);
+}
+
+void GxEPD2_290_T5::drawImagePart(const uint8_t bitmap[], int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                               int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
+{
+  writeImagePart(bitmap, x_part, y_part, w_bitmap, h_bitmap, x, y, w, h, invert, mirror_y, pgm);
+  refresh(x, y, w, h);
+  writeImagePart(bitmap, x_part, y_part, w_bitmap, h_bitmap, x, y, w, h, invert, mirror_y, pgm);
 }
 
 void GxEPD2_290_T5::drawImage(const uint8_t* black, const uint8_t* color, int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
 {
   writeImage(black, color, x, y, w, h, invert, mirror_y, pgm);
   refresh(x, y, w, h);
+  writeImage(black, color, x, y, w, h, invert, mirror_y, pgm);
+}
+
+void GxEPD2_290_T5::drawImagePart(const uint8_t* black, const uint8_t* color, int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                               int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
+{
+  writeImagePart(black, color, x_part, y_part, w_bitmap, h_bitmap, x, y, w, h, invert, mirror_y, pgm);
+  refresh(x, y, w, h);
+  writeImagePart(black, color, x_part, y_part, w_bitmap, h_bitmap, x, y, w, h, invert, mirror_y, pgm);
 }
 
 void GxEPD2_290_T5::drawNative(const uint8_t* data1, const uint8_t* data2, int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
 {
   writeNative(data1, data2, x, y, w, h, invert, mirror_y, pgm);
   refresh(x, y, w, h);
+  writeNative(data1, data2, x, y, w, h, invert, mirror_y, pgm);
 }
 
 void GxEPD2_290_T5::refresh(bool partial_update_mode)

src/epd/GxEPD2_290_T5.h

@@ -37,12 +37,20 @@ class GxEPD2_290_T5 : public GxEPD2_EPD
     void writeScreenBuffer(uint8_t value = 0xFF); // init controller memory (default white)
     // write to controller memory, without screen refresh; x and w should be multiple of 8
     void writeImage(const uint8_t bitmap[], int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
+    void writeImagePart(const uint8_t bitmap[], int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                        int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     void writeImage(const uint8_t* black, const uint8_t* color, int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
+    void writeImagePart(const uint8_t* black, const uint8_t* color, int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                        int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     // write sprite of native data to controller memory, without screen refresh; x and w should be multiple of 8
     void writeNative(const uint8_t* data1, const uint8_t* data2, int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     // write to controller memory, with screen refresh; x and w should be multiple of 8
     void drawImage(const uint8_t bitmap[], int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
+    void drawImagePart(const uint8_t bitmap[], int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                       int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     void drawImage(const uint8_t* black, const uint8_t* color, int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
+    void drawImagePart(const uint8_t* black, const uint8_t* color, int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                       int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     // write sprite of native data to controller memory, with screen refresh; x and w should be multiple of 8
     void drawNative(const uint8_t* data1, const uint8_t* data2, int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     void refresh(bool partial_update_mode = false); // screen refresh from controller memory to full screen

src/epd/GxEPD2_420.cpp

@@ -115,6 +115,59 @@ void GxEPD2_420::writeImage(const uint8_t bitmap[], int16_t x, int16_t y, int16_
   delay(1); // yield() to avoid WDT on ESP8266 and ESP32
 }
 
+void GxEPD2_420::writeImagePart(const uint8_t bitmap[], int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                                int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
+{
+  delay(1); // yield() to avoid WDT on ESP8266 and ESP32
+  if ((w_bitmap < 0) || (h_bitmap < 0) || (w < 0) || (h < 0)) return;
+  if ((x_part < 0) || (x_part >= w_bitmap)) return;
+  if ((y_part < 0) || (y_part >= h_bitmap)) return;
+  int16_t wb_bitmap = (w_bitmap + 7) / 8; // width bytes, bitmaps are padded
+  x_part -= x_part % 8; // byte boundary
+  w = w_bitmap - x_part < w ? w_bitmap - x_part : w; // limit
+  h = h_bitmap - y_part < h ? h_bitmap - y_part : h; // limit
+  x -= x % 8; // byte boundary
+  w = 8 * ((w + 7) / 8); // byte boundary, bitmaps are padded
+  int16_t x1 = x < 0 ? 0 : x; // limit
+  int16_t y1 = y < 0 ? 0 : y; // limit
+  int16_t w1 = x + w < int16_t(WIDTH) ? w : int16_t(WIDTH) - x; // limit
+  int16_t h1 = y + h < int16_t(HEIGHT) ? h : int16_t(HEIGHT) - y; // limit
+  int16_t dx = x1 - x;
+  int16_t dy = y1 - y;
+  w1 -= dx;
+  h1 -= dy;
+  if ((w1 <= 0) || (h1 <= 0)) return;
+  if (!_using_partial_mode) _Init_Part();
+  _writeCommand(0x91); // partial in
+  _setPartialRamArea(x1, y1, w1, h1);
+  _writeCommand(0x13);
+  for (int16_t i = 0; i < h1; i++)
+  {
+    for (int16_t j = 0; j < w1 / 8; j++)
+    {
+      uint8_t data;
+      // use wb_bitmap, h_bitmap of bitmap for index!
+      int16_t idx = mirror_y ? x_part / 8 + j + dx / 8 + ((h_bitmap - 1 - (y_part + i + dy))) * wb_bitmap : x_part / 8 + j + dx / 8 + (y_part + i + dy) * wb_bitmap;
+      if (pgm)
+      {
+#if defined(__AVR) || defined(ESP8266) || defined(ESP32)
+        data = pgm_read_byte(&bitmap[idx]);
+#else
+        data = bitmap[idx];
+#endif
+      }
+      else
+      {
+        data = bitmap[idx];
+      }
+      if (invert) data = ~data;
+      _writeData(data);
+    }
+  }
+  _writeCommand(0x92); // partial out
+  delay(1); // yield() to avoid WDT on ESP8266 and ESP32
+}
+
 void GxEPD2_420::writeImage(const uint8_t* black, const uint8_t* color, int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
 {
   if (black)
@@ -123,6 +176,15 @@ void GxEPD2_420::writeImage(const uint8_t* black, const uint8_t* color, int16_t
   }
 }
 
+void GxEPD2_420::writeImagePart(const uint8_t* black, const uint8_t* color, int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                                int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
+{
+  if (black)
+  {
+    writeImagePart(black, x_part, y_part, w_bitmap, h_bitmap, x, y, w, h, invert, mirror_y, pgm);
+  }
+}
+
 void GxEPD2_420::writeNative(const uint8_t* data1, const uint8_t* data2, int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
 {
   if (data1)
@@ -135,18 +197,37 @@ void GxEPD2_420::drawImage(const uint8_t bitmap[], int16_t x, int16_t y, int16_t
 {
   writeImage(bitmap, x, y, w, h, invert, mirror_y, pgm);
   refresh(x, y, w, h);
+  writeImage(bitmap, x, y, w, h, invert, mirror_y, pgm);
+}
+
+void GxEPD2_420::drawImagePart(const uint8_t bitmap[], int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                               int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
+{
+  writeImagePart(bitmap, x_part, y_part, w_bitmap, h_bitmap, x, y, w, h, invert, mirror_y, pgm);
+  refresh(x, y, w, h);
+  writeImagePart(bitmap, x_part, y_part, w_bitmap, h_bitmap, x, y, w, h, invert, mirror_y, pgm);
 }
 
 void GxEPD2_420::drawImage(const uint8_t* black, const uint8_t* color, int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
 {
   writeImage(black, color, x, y, w, h, invert, mirror_y, pgm);
   refresh(x, y, w, h);
+  writeImage(black, color, x, y, w, h, invert, mirror_y, pgm);
+}
+
+void GxEPD2_420::drawImagePart(const uint8_t* black, const uint8_t* color, int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                               int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
+{
+  writeImagePart(black, color, x_part, y_part, w_bitmap, h_bitmap, x, y, w, h, invert, mirror_y, pgm);
+  refresh(x, y, w, h);
+  writeImagePart(black, color, x_part, y_part, w_bitmap, h_bitmap, x, y, w, h, invert, mirror_y, pgm);
 }
 
 void GxEPD2_420::drawNative(const uint8_t* data1, const uint8_t* data2, int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
 {
   writeNative(data1, data2, x, y, w, h, invert, mirror_y, pgm);
   refresh(x, y, w, h);
+  writeNative(data1, data2, x, y, w, h, invert, mirror_y, pgm);
 }
 
 void GxEPD2_420::refresh(bool partial_update_mode)

src/epd/GxEPD2_420.h

@@ -37,12 +37,20 @@ class GxEPD2_420 : public GxEPD2_EPD
     void writeScreenBuffer(uint8_t value = 0xFF); // init controller memory (default white)
     // write to controller memory, without screen refresh; x and w should be multiple of 8
     void writeImage(const uint8_t bitmap[], int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
+    void writeImagePart(const uint8_t bitmap[], int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                        int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     void writeImage(const uint8_t* black, const uint8_t* color, int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
+    void writeImagePart(const uint8_t* black, const uint8_t* color, int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                        int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     // write sprite of native data to controller memory, without screen refresh; x and w should be multiple of 8
     void writeNative(const uint8_t* data1, const uint8_t* data2, int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     // write to controller memory, with screen refresh; x and w should be multiple of 8
     void drawImage(const uint8_t bitmap[], int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
+    void drawImagePart(const uint8_t bitmap[], int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                       int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     void drawImage(const uint8_t* black, const uint8_t* color, int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
+    void drawImagePart(const uint8_t* black, const uint8_t* color, int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                       int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     // write sprite of native data to controller memory, with screen refresh; x and w should be multiple of 8
     void drawNative(const uint8_t* data1, const uint8_t* data2, int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     void refresh(bool partial_update_mode = false); // screen refresh from controller memory to full screen

src/epd/GxEPD2_583.cpp

@@ -74,7 +74,7 @@ void GxEPD2_583::_writeScreenBuffer(uint8_t value)
 void GxEPD2_583::writeImage(const uint8_t bitmap[], int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
 {
   delay(1); // yield() to avoid WDT on ESP8266 and ESP32
-  int16_t wb = (w + 7) / 8; // width bytes, bitmaps are padded
+  uint16_t wb = (w + 7) / 8; // width bytes, bitmaps are padded
   x -= x % 8; // byte boundary
   w = wb * 8; // byte boundary
   int16_t x1 = x < 0 ? 0 : x; // limit
@@ -96,7 +96,60 @@ void GxEPD2_583::writeImage(const uint8_t bitmap[], int16_t x, int16_t y, int16_
     {
       uint8_t data;
       // use wb, h of bitmap for index!
-      int16_t idx = mirror_y ? j + dx / 8 + ((h - 1 - (i + dy))) * wb : j + dx / 8 + (i + dy) * wb;
+      uint16_t idx = mirror_y ? j + dx / 8 + uint16_t((h - 1 - (i + dy))) * wb : j + dx / 8 + uint16_t(i + dy) * wb;
+      if (pgm)
+      {
+#if defined(__AVR) || defined(ESP8266) || defined(ESP32)
+        data = pgm_read_byte(&bitmap[idx]);
+#else
+        data = bitmap[idx];
+#endif
+      }
+      else
+      {
+        data = bitmap[idx];
+      }
+      if (invert) data = ~data;
+      _send8pixel(~data);
+    }
+  }
+  _writeCommand(0x92); // partial out
+  delay(1); // yield() to avoid WDT on ESP8266 and ESP32
+}
+
+void GxEPD2_583::writeImagePart(const uint8_t bitmap[], int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                                int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
+{
+  delay(1); // yield() to avoid WDT on ESP8266 and ESP32
+  if ((w_bitmap < 0) || (h_bitmap < 0) || (w < 0) || (h < 0)) return;
+  if ((x_part < 0) || (x_part >= w_bitmap)) return;
+  if ((y_part < 0) || (y_part >= h_bitmap)) return;
+  uint16_t wb_bitmap = (w_bitmap + 7) / 8; // width bytes, bitmaps are padded
+  x_part -= x_part % 8; // byte boundary
+  w = w_bitmap - x_part < w ? w_bitmap - x_part : w; // limit
+  h = h_bitmap - y_part < h ? h_bitmap - y_part : h; // limit
+  x -= x % 8; // byte boundary
+  w = 8 * ((w + 7) / 8); // byte boundary, bitmaps are padded
+  int16_t x1 = x < 0 ? 0 : x; // limit
+  int16_t y1 = y < 0 ? 0 : y; // limit
+  int16_t w1 = x + w < int16_t(WIDTH) ? w : int16_t(WIDTH) - x; // limit
+  int16_t h1 = y + h < int16_t(HEIGHT) ? h : int16_t(HEIGHT) - y; // limit
+  int16_t dx = x1 - x;
+  int16_t dy = y1 - y;
+  w1 -= dx;
+  h1 -= dy;
+  if ((w1 <= 0) || (h1 <= 0)) return;
+  if (!_using_partial_mode) _Init_Part();
+  _writeCommand(0x91); // partial in
+  _setPartialRamArea(x1, y1, w1, h1);
+  _writeCommand(0x10);
+  for (int16_t i = 0; i < h1; i++)
+  {
+    for (int16_t j = 0; j < w1 / 8; j++)
+    {
+      uint8_t data;
+      // use wb_bitmap, h_bitmap of bitmap for index!
+      uint16_t idx = mirror_y ? x_part / 8 + j + dx / 8 + uint16_t((h_bitmap - 1 - (y_part + i + dy))) * wb_bitmap : x_part / 8 + j + dx / 8 + uint16_t(y_part + i + dy) * wb_bitmap;
       if (pgm)
       {
 #if defined(__AVR) || defined(ESP8266) || defined(ESP32)
@@ -125,6 +178,15 @@ void GxEPD2_583::writeImage(const uint8_t* black, const uint8_t* color, int16_t
   }
 }
 
+void GxEPD2_583::writeImagePart(const uint8_t* black, const uint8_t* color, int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                                int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
+{
+  if (black)
+  {
+    writeImagePart(black, x_part, y_part, w_bitmap, h_bitmap, x, y, w, h, invert, mirror_y, pgm);
+  }
+}
+
 void GxEPD2_583::writeNative(const uint8_t* data1, const uint8_t* data2, int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
 {
   if (data1)
@@ -180,12 +242,26 @@ void GxEPD2_583::drawImage(const uint8_t bitmap[], int16_t x, int16_t y, int16_t
   refresh(x, y, w, h);
 }
 
+void GxEPD2_583::drawImagePart(const uint8_t bitmap[], int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                               int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
+{
+  writeImagePart(bitmap, x_part, y_part, w_bitmap, h_bitmap, x, y, w, h, invert, mirror_y, pgm);
+  refresh(x, y, w, h);
+}
+
 void GxEPD2_583::drawImage(const uint8_t* black, const uint8_t* color, int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
 {
   writeImage(black, color, x, y, w, h, invert, mirror_y, pgm);
   refresh(x, y, w, h);
 }
 
+void GxEPD2_583::drawImagePart(const uint8_t* black, const uint8_t* color, int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                               int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
+{
+  writeImagePart(black, color, x_part, y_part, w_bitmap, h_bitmap, x, y, w, h, invert, mirror_y, pgm);
+  refresh(x, y, w, h);
+}
+
 void GxEPD2_583::drawNative(const uint8_t* data1, const uint8_t* data2, int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
 {
   writeNative(data1, data2, x, y, w, h, invert, mirror_y, pgm);

src/epd/GxEPD2_583.h

@@ -37,12 +37,20 @@ class GxEPD2_583 : public GxEPD2_EPD
     void writeScreenBuffer(uint8_t value = 0x33); // init controller memory (default white)
     // write to controller memory, without screen refresh; x and w should be multiple of 8
     void writeImage(const uint8_t bitmap[], int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
+    void writeImagePart(const uint8_t bitmap[], int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                        int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     void writeImage(const uint8_t* black, const uint8_t* color, int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
+    void writeImagePart(const uint8_t* black, const uint8_t* color, int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                        int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     // write sprite of native data to controller memory, without screen refresh; x and w should be multiple of 8
     void writeNative(const uint8_t* data1, const uint8_t* data2, int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     // write to controller memory, with screen refresh; x and w should be multiple of 8
     void drawImage(const uint8_t bitmap[], int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
+    void drawImagePart(const uint8_t bitmap[], int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                       int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     void drawImage(const uint8_t* black, const uint8_t* color, int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
+    void drawImagePart(const uint8_t* black, const uint8_t* color, int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                       int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     // write sprite of native data to controller memory, with screen refresh; x and w should be multiple of 8
     void drawNative(const uint8_t* data1, const uint8_t* data2, int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     void refresh(bool partial_update_mode = false); // screen refresh from controller memory to full screen

src/epd/GxEPD2_750.cpp

@@ -74,7 +74,7 @@ void GxEPD2_750::_writeScreenBuffer(uint8_t value)
 void GxEPD2_750::writeImage(const uint8_t bitmap[], int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
 {
   delay(1); // yield() to avoid WDT on ESP8266 and ESP32
-  int16_t wb = (w + 7) / 8; // width bytes, bitmaps are padded
+  uint16_t wb = (w + 7) / 8; // width bytes, bitmaps are padded
   x -= x % 8; // byte boundary
   w = wb * 8; // byte boundary
   int16_t x1 = x < 0 ? 0 : x; // limit
@@ -96,7 +96,60 @@ void GxEPD2_750::writeImage(const uint8_t bitmap[], int16_t x, int16_t y, int16_
     {
       uint8_t data;
       // use wb, h of bitmap for index!
-      int16_t idx = mirror_y ? j + dx / 8 + ((h - 1 - (i + dy))) * wb : j + dx / 8 + (i + dy) * wb;
+      uint16_t idx = mirror_y ? j + dx / 8 + uint16_t((h - 1 - (i + dy))) * wb : j + dx / 8 + uint16_t(i + dy) * wb;
+      if (pgm)
+      {
+#if defined(__AVR) || defined(ESP8266) || defined(ESP32)
+        data = pgm_read_byte(&bitmap[idx]);
+#else
+        data = bitmap[idx];
+#endif
+      }
+      else
+      {
+        data = bitmap[idx];
+      }
+      if (invert) data = ~data;
+      _send8pixel(~data);
+    }
+  }
+  _writeCommand(0x92); // partial out
+  delay(1); // yield() to avoid WDT on ESP8266 and ESP32
+}
+
+void GxEPD2_750::writeImagePart(const uint8_t bitmap[], int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                                int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
+{
+  delay(1); // yield() to avoid WDT on ESP8266 and ESP32
+  if ((w_bitmap < 0) || (h_bitmap < 0) || (w < 0) || (h < 0)) return;
+  if ((x_part < 0) || (x_part >= w_bitmap)) return;
+  if ((y_part < 0) || (y_part >= h_bitmap)) return;
+  uint16_t wb_bitmap = (w_bitmap + 7) / 8; // width bytes, bitmaps are padded
+  x_part -= x_part % 8; // byte boundary
+  w = w_bitmap - x_part < w ? w_bitmap - x_part : w; // limit
+  h = h_bitmap - y_part < h ? h_bitmap - y_part : h; // limit
+  x -= x % 8; // byte boundary
+  w = 8 * ((w + 7) / 8); // byte boundary, bitmaps are padded
+  int16_t x1 = x < 0 ? 0 : x; // limit
+  int16_t y1 = y < 0 ? 0 : y; // limit
+  int16_t w1 = x + w < int16_t(WIDTH) ? w : int16_t(WIDTH) - x; // limit
+  int16_t h1 = y + h < int16_t(HEIGHT) ? h : int16_t(HEIGHT) - y; // limit
+  int16_t dx = x1 - x;
+  int16_t dy = y1 - y;
+  w1 -= dx;
+  h1 -= dy;
+  if ((w1 <= 0) || (h1 <= 0)) return;
+  if (!_using_partial_mode) _Init_Part();
+  _writeCommand(0x91); // partial in
+  _setPartialRamArea(x1, y1, w1, h1);
+  _writeCommand(0x10);
+  for (int16_t i = 0; i < h1; i++)
+  {
+    for (int16_t j = 0; j < w1 / 8; j++)
+    {
+      uint8_t data;
+      // use wb_bitmap, h_bitmap of bitmap for index!
+      uint16_t idx = mirror_y ? x_part / 8 + j + dx / 8 + uint16_t((h_bitmap - 1 - (y_part + i + dy))) * wb_bitmap : x_part / 8 + j + dx / 8 + uint16_t(y_part + i + dy) * wb_bitmap;
       if (pgm)
       {
 #if defined(__AVR) || defined(ESP8266) || defined(ESP32)
@@ -125,6 +178,15 @@ void GxEPD2_750::writeImage(const uint8_t* black, const uint8_t* color, int16_t
   }
 }
 
+void GxEPD2_750::writeImagePart(const uint8_t* black, const uint8_t* color, int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                                int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
+{
+  if (black)
+  {
+    writeImagePart(black, x_part, y_part, w_bitmap, h_bitmap, x, y, w, h, invert, mirror_y, pgm);
+  }
+}
+
 void GxEPD2_750::writeNative(const uint8_t* data1, const uint8_t* data2, int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
 {
   if (data1)
@@ -180,12 +242,26 @@ void GxEPD2_750::drawImage(const uint8_t bitmap[], int16_t x, int16_t y, int16_t
   refresh(x, y, w, h);
 }
 
+void GxEPD2_750::drawImagePart(const uint8_t bitmap[], int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                               int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
+{
+  writeImagePart(bitmap, x_part, y_part, w_bitmap, h_bitmap, x, y, w, h, invert, mirror_y, pgm);
+  refresh(x, y, w, h);
+}
+
 void GxEPD2_750::drawImage(const uint8_t* black, const uint8_t* color, int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
 {
   writeImage(black, color, x, y, w, h, invert, mirror_y, pgm);
   refresh(x, y, w, h);
 }
 
+void GxEPD2_750::drawImagePart(const uint8_t* black, const uint8_t* color, int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                               int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
+{
+  writeImagePart(black, color, x_part, y_part, w_bitmap, h_bitmap, x, y, w, h, invert, mirror_y, pgm);
+  refresh(x, y, w, h);
+}
+
 void GxEPD2_750::drawNative(const uint8_t* data1, const uint8_t* data2, int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
 {
   writeNative(data1, data2, x, y, w, h, invert, mirror_y, pgm);

src/epd/GxEPD2_750.h

@@ -37,12 +37,20 @@ class GxEPD2_750 : public GxEPD2_EPD
     void writeScreenBuffer(uint8_t value = 0x33); // init controller memory (default white)
     // write to controller memory, without screen refresh; x and w should be multiple of 8
     void writeImage(const uint8_t bitmap[], int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
+    void writeImagePart(const uint8_t bitmap[], int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                        int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     void writeImage(const uint8_t* black, const uint8_t* color, int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
+    void writeImagePart(const uint8_t* black, const uint8_t* color, int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                        int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     // write sprite of native data to controller memory, without screen refresh; x and w should be multiple of 8
     void writeNative(const uint8_t* data1, const uint8_t* data2, int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     // write to controller memory, with screen refresh; x and w should be multiple of 8
     void drawImage(const uint8_t bitmap[], int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
+    void drawImagePart(const uint8_t bitmap[], int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                       int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     void drawImage(const uint8_t* black, const uint8_t* color, int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
+    void drawImagePart(const uint8_t* black, const uint8_t* color, int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                       int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     // write sprite of native data to controller memory, with screen refresh; x and w should be multiple of 8
     void drawNative(const uint8_t* data1, const uint8_t* data2, int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     void refresh(bool partial_update_mode = false); // screen refresh from controller memory to full screen

src/epd3c/GxEPD2_154c.cpp

@@ -198,6 +198,101 @@ void GxEPD2_154c::writeImage(const uint8_t* black, const uint8_t* color, int16_t
   delay(1); // yield() to avoid WDT on ESP8266 and ESP32
 }
 
+void GxEPD2_154c::writeImagePart(const uint8_t bitmap[], int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                                 int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
+{
+  writeImagePart(bitmap, NULL, x_part, y_part, w_bitmap, h_bitmap, x, y, w, h, invert, mirror_y, pgm);
+}
+
+void GxEPD2_154c::writeImagePart(const uint8_t* black, const uint8_t* color, int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                                 int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
+{
+  delay(1); // yield() to avoid WDT on ESP8266 and ESP32
+  if ((w_bitmap < 0) || (h_bitmap < 0) || (w < 0) || (h < 0)) return;
+  if ((x_part < 0) || (x_part >= w_bitmap)) return;
+  if ((y_part < 0) || (y_part >= h_bitmap)) return;
+  int16_t wb_bitmap = (w_bitmap + 7) / 8; // width bytes, bitmaps are padded
+  x_part -= x_part % 8; // byte boundary
+  w = w_bitmap - x_part < w ? w_bitmap - x_part : w; // limit
+  h = h_bitmap - y_part < h ? h_bitmap - y_part : h; // limit
+  x -= x % 8; // byte boundary
+  w = 8 * ((w + 7) / 8); // byte boundary, bitmaps are padded
+  int16_t x1 = x < 0 ? 0 : x; // limit
+  int16_t y1 = y < 0 ? 0 : y; // limit
+  int16_t w1 = x + w < int16_t(WIDTH) ? w : int16_t(WIDTH) - x; // limit
+  int16_t h1 = y + h < int16_t(HEIGHT) ? h : int16_t(HEIGHT) - y; // limit
+  int16_t dx = x1 - x;
+  int16_t dy = y1 - y;
+  w1 -= dx;
+  h1 -= dy;
+  if ((w1 <= 0) || (h1 <= 0)) return;
+  _Init_Full();
+  _writeCommand(0x10);
+  for (int16_t i = 0; i < HEIGHT; i++)
+  {
+    for (int16_t j = 0; j < WIDTH; j += 8)
+    {
+      uint8_t data = 0xFF;
+      if (black)
+      {
+        if ((j >= x1) && (j <= x1 + w) && (i >= y1) && (i < y1 + h))
+        {
+          // use wb_bitmap, h_bitmap of bitmap for index!
+          //int16_t idx = mirror_y ? x_part / 8 + j + dx / 8 + ((h_bitmap - 1 - (y_part + i + dy))) * wb_bitmap : x_part / 8 + j + dx / 8 + (y_part + i + dy) * wb_bitmap;
+          int16_t idx = mirror_y ? (x_part + j - x1) / 8 + ((h_bitmap - 1 - (y_part + i - y1))) * wb_bitmap : (x_part + j - x1) / 8 + (y_part + i - y1) * wb_bitmap;
+          if (pgm)
+          {
+#if defined(__AVR) || defined(ESP8266) || defined(ESP32)
+            data = pgm_read_byte(&black[idx]);
+#else
+            data = black[idx];
+#endif
+          }
+          else
+          {
+            data = black[idx];
+          }
+          if (invert) data = ~data;
+        }
+      }
+      //_writeData(data);
+      _writeData(bw2grey[(data & 0xF0) >> 4]);
+      _writeData(bw2grey[data & 0x0F]);
+    }
+  }
+  _writeCommand(0x13);
+  for (int16_t i = 0; i < HEIGHT; i++)
+  {
+    for (int16_t j = 0; j < WIDTH; j += 8)
+    {
+      uint8_t data = 0xFF;
+      if (color)
+      {
+        if ((j >= x1) && (j <= x1 + w) && (i >= y1) && (i < y1 + h))
+        {
+          // use wb_bitmap, h_bitmap of bitmap for index!
+          int16_t idx = mirror_y ? (x_part + j - x1) / 8 + ((h_bitmap - 1 - (y_part + i - y1))) * wb_bitmap : (x_part + j - x1) / 8 + (y_part + i - y1) * wb_bitmap;
+          if (pgm)
+          {
+#if defined(__AVR) || defined(ESP8266) || defined(ESP32)
+            data = pgm_read_byte(&color[idx]);
+#else
+            data = color[idx];
+#endif
+          }
+          else
+          {
+            data = color[idx];
+          }
+          if (invert) data = ~data;
+        }
+      }
+      _writeData(data);
+    }
+  }
+  delay(1); // yield() to avoid WDT on ESP8266 and ESP32
+}
+
 void GxEPD2_154c::writeNative(const uint8_t* data1, const uint8_t* data2, int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
 {
   if (data1)
@@ -212,12 +307,26 @@ void GxEPD2_154c::drawImage(const uint8_t bitmap[], int16_t x, int16_t y, int16_
   refresh(x, y, w, h);
 }
 
+void GxEPD2_154c::drawImagePart(const uint8_t bitmap[], int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                                int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
+{
+  writeImagePart(bitmap, x_part, y_part, w_bitmap, h_bitmap, x, y, w, h, invert, mirror_y, pgm);
+  refresh(x, y, w, h);
+}
+
 void GxEPD2_154c::drawImage(const uint8_t* black, const uint8_t* color, int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
 {
   writeImage(black, color, x, y, w, h, invert, mirror_y, pgm);
   refresh(x, y, w, h);
 }
 
+void GxEPD2_154c::drawImagePart(const uint8_t* black, const uint8_t* color, int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                                int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
+{
+  writeImagePart(black, color, x_part, y_part, w_bitmap, h_bitmap, x, y, w, h, invert, mirror_y, pgm);
+  refresh(x, y, w, h);
+}
+
 void GxEPD2_154c::drawNative(const uint8_t* data1, const uint8_t* data2, int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
 {
   writeNative(data1, data2, x, y, w, h, invert, mirror_y, pgm);

src/epd3c/GxEPD2_154c.h

@@ -41,12 +41,20 @@ class GxEPD2_154c : public GxEPD2_EPD
     void writeScreenBuffer(uint8_t black_value, uint8_t color_value); // init controller memory
     // write to controller memory, without screen refresh; x and w should be multiple of 8
     void writeImage(const uint8_t bitmap[], int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
+    void writeImagePart(const uint8_t bitmap[], int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                        int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     void writeImage(const uint8_t* black, const uint8_t* color, int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
+    void writeImagePart(const uint8_t* black, const uint8_t* color, int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                        int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     // write sprite of native data to controller memory, without screen refresh; x and w should be multiple of 8
     void writeNative(const uint8_t* data1, const uint8_t* data2, int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     // write to controller memory, with screen refresh; x and w should be multiple of 8
     void drawImage(const uint8_t bitmap[], int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
+    void drawImagePart(const uint8_t bitmap[], int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                       int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     void drawImage(const uint8_t* black, const uint8_t* color, int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
+    void drawImagePart(const uint8_t* black, const uint8_t* color, int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                       int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     // write sprite of native data to controller memory, with screen refresh; x and w should be multiple of 8
     void drawNative(const uint8_t* data1, const uint8_t* data2, int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     void refresh(bool partial_update_mode = false); // screen refresh from controller memory to full screen

src/epd3c/GxEPD2_213c.cpp

@@ -149,6 +149,92 @@ void GxEPD2_213c::writeImage(const uint8_t* black, const uint8_t* color, int16_t
   delay(1); // yield() to avoid WDT on ESP8266 and ESP32
 }
 
+void GxEPD2_213c::writeImagePart(const uint8_t bitmap[], int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                                 int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
+{
+  writeImagePart(bitmap, NULL, x_part, y_part, w_bitmap, h_bitmap, x, y, w, h, invert, mirror_y, pgm);
+}
+
+void GxEPD2_213c::writeImagePart(const uint8_t* black, const uint8_t* color, int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                                 int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
+{
+  delay(1); // yield() to avoid WDT on ESP8266 and ESP32
+  if ((w_bitmap < 0) || (h_bitmap < 0) || (w < 0) || (h < 0)) return;
+  if ((x_part < 0) || (x_part >= w_bitmap)) return;
+  if ((y_part < 0) || (y_part >= h_bitmap)) return;
+  int16_t wb_bitmap = (w_bitmap + 7) / 8; // width bytes, bitmaps are padded
+  x_part -= x_part % 8; // byte boundary
+  w = w_bitmap - x_part < w ? w_bitmap - x_part : w; // limit
+  h = h_bitmap - y_part < h ? h_bitmap - y_part : h; // limit
+  x -= x % 8; // byte boundary
+  w = 8 * ((w + 7) / 8); // byte boundary, bitmaps are padded
+  int16_t x1 = x < 0 ? 0 : x; // limit
+  int16_t y1 = y < 0 ? 0 : y; // limit
+  int16_t w1 = x + w < int16_t(WIDTH) ? w : int16_t(WIDTH) - x; // limit
+  int16_t h1 = y + h < int16_t(HEIGHT) ? h : int16_t(HEIGHT) - y; // limit
+  int16_t dx = x1 - x;
+  int16_t dy = y1 - y;
+  w1 -= dx;
+  h1 -= dy;
+  if ((w1 <= 0) || (h1 <= 0)) return;
+  if (!_using_partial_mode) _Init_Part();
+  _writeCommand(0x91); // partial in
+  _setPartialRamArea(x1, y1, w1, h1);
+  _writeCommand(0x10);
+  for (int16_t i = 0; i < h1; i++)
+  {
+    for (int16_t j = 0; j < w1 / 8; j++)
+    {
+      uint8_t data;
+      // use wb_bitmap, h_bitmap of bitmap for index!
+      int16_t idx = mirror_y ? x_part / 8 + j + dx / 8 + ((h_bitmap - 1 - (y_part + i + dy))) * wb_bitmap : x_part / 8 + j + dx / 8 + (y_part + i + dy) * wb_bitmap;
+      if (pgm)
+      {
+#if defined(__AVR) || defined(ESP8266) || defined(ESP32)
+        data = pgm_read_byte(&black[idx]);
+#else
+        data = black[idx];
+#endif
+      }
+      else
+      {
+        data = black[idx];
+      }
+      if (invert) data = ~data;
+      _writeData(data);
+    }
+  }
+  _writeCommand(0x13);
+  for (int16_t i = 0; i < h1; i++)
+  {
+    for (int16_t j = 0; j < w1 / 8; j++)
+    {
+      uint8_t data = 0xFF;
+      if (color)
+      {
+        // use wb_bitmap, h_bitmap of bitmap for index!
+        int16_t idx = mirror_y ? x_part / 8 + j + dx / 8 + ((h_bitmap - 1 - (y_part + i + dy))) * wb_bitmap : x_part / 8 + j + dx / 8 + (y_part + i + dy) * wb_bitmap;
+        if (pgm)
+        {
+#if defined(__AVR) || defined(ESP8266) || defined(ESP32)
+          data = pgm_read_byte(&color[idx]);
+#else
+          data = color[idx];
+#endif
+        }
+        else
+        {
+          data = color[idx];
+        }
+        if (invert) data = ~data;
+      }
+      _writeData(data);
+    }
+  }
+  _writeCommand(0x92); // partial out
+  delay(1); // yield() to avoid WDT on ESP8266 and ESP32
+}
+
 void GxEPD2_213c::writeNative(const uint8_t* data1, const uint8_t* data2, int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
 {
   if (data1)
@@ -163,12 +249,26 @@ void GxEPD2_213c::drawImage(const uint8_t bitmap[], int16_t x, int16_t y, int16_
   refresh(x, y, w, h);
 }
 
+void GxEPD2_213c::drawImagePart(const uint8_t bitmap[], int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                               int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
+{
+  writeImagePart(bitmap, x_part, y_part, w_bitmap, h_bitmap, x, y, w, h, invert, mirror_y, pgm);
+  refresh(x, y, w, h);
+}
+
 void GxEPD2_213c::drawImage(const uint8_t* black, const uint8_t* color, int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
 {
   writeImage(black, color, x, y, w, h, invert, mirror_y, pgm);
   refresh(x, y, w, h);
 }
 
+void GxEPD2_213c::drawImagePart(const uint8_t* black, const uint8_t* color, int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                               int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
+{
+  writeImagePart(black, color, x_part, y_part, w_bitmap, h_bitmap, x, y, w, h, invert, mirror_y, pgm);
+  refresh(x, y, w, h);
+}
+
 void GxEPD2_213c::drawNative(const uint8_t* data1, const uint8_t* data2, int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
 {
   writeNative(data1, data2, x, y, w, h, invert, mirror_y, pgm);

src/epd3c/GxEPD2_213c.h

@@ -39,12 +39,20 @@ class GxEPD2_213c : public GxEPD2_EPD
     void writeScreenBuffer(uint8_t black_value, uint8_t color_value); // init controller memory
     // write to controller memory, without screen refresh; x and w should be multiple of 8
     void writeImage(const uint8_t bitmap[], int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
+    void writeImagePart(const uint8_t bitmap[], int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                        int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     void writeImage(const uint8_t* black, const uint8_t* color, int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
+    void writeImagePart(const uint8_t* black, const uint8_t* color, int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                        int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     // write sprite of native data to controller memory, without screen refresh; x and w should be multiple of 8
     void writeNative(const uint8_t* data1, const uint8_t* data2, int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     // write to controller memory, with screen refresh; x and w should be multiple of 8
     void drawImage(const uint8_t bitmap[], int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
+    void drawImagePart(const uint8_t bitmap[], int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                       int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     void drawImage(const uint8_t* black, const uint8_t* color, int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
+    void drawImagePart(const uint8_t* black, const uint8_t* color, int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                       int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     // write sprite of native data to controller memory, with screen refresh; x and w should be multiple of 8
     void drawNative(const uint8_t* data1, const uint8_t* data2, int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     void refresh(bool partial_update_mode = false); // screen refresh from controller memory to full screen

src/epd3c/GxEPD2_270c.cpp

@@ -136,6 +136,89 @@ void GxEPD2_270c::writeImage(const uint8_t* black, const uint8_t* color, int16_t
   delay(1); // yield() to avoid WDT on ESP8266 and ESP32
 }
 
+void GxEPD2_270c::writeImagePart(const uint8_t bitmap[], int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                                 int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
+{
+  writeImagePart(bitmap, NULL, x_part, y_part, w_bitmap, h_bitmap, x, y, w, h, invert, mirror_y, pgm);
+}
+
+void GxEPD2_270c::writeImagePart(const uint8_t* black, const uint8_t* color, int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                                 int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
+{
+  delay(1); // yield() to avoid WDT on ESP8266 and ESP32
+  if ((w_bitmap < 0) || (h_bitmap < 0) || (w < 0) || (h < 0)) return;
+  if ((x_part < 0) || (x_part >= w_bitmap)) return;
+  if ((y_part < 0) || (y_part >= h_bitmap)) return;
+  int16_t wb_bitmap = (w_bitmap + 7) / 8; // width bytes, bitmaps are padded
+  x_part -= x_part % 8; // byte boundary
+  w = w_bitmap - x_part < w ? w_bitmap - x_part : w; // limit
+  h = h_bitmap - y_part < h ? h_bitmap - y_part : h; // limit
+  x -= x % 8; // byte boundary
+  w = 8 * ((w + 7) / 8); // byte boundary, bitmaps are padded
+  int16_t x1 = x < 0 ? 0 : x; // limit
+  int16_t y1 = y < 0 ? 0 : y; // limit
+  int16_t w1 = x + w < int16_t(WIDTH) ? w : int16_t(WIDTH) - x; // limit
+  int16_t h1 = y + h < int16_t(HEIGHT) ? h : int16_t(HEIGHT) - y; // limit
+  int16_t dx = x1 - x;
+  int16_t dy = y1 - y;
+  w1 -= dx;
+  h1 -= dy;
+  if ((w1 <= 0) || (h1 <= 0)) return;
+  if (!_using_partial_mode) _Init_Part();
+  _setPartialRamArea_270c(0x14, x1, y1, w1, h1);
+  for (int16_t i = 0; i < h1; i++)
+  {
+    for (int16_t j = 0; j < w1 / 8; j++)
+    {
+      uint8_t data;
+      // use wb_bitmap, h_bitmap of bitmap for index!
+      int16_t idx = mirror_y ? x_part / 8 + j + dx / 8 + ((h_bitmap - 1 - (y_part + i + dy))) * wb_bitmap : x_part / 8 + j + dx / 8 + (y_part + i + dy) * wb_bitmap;
+      if (pgm)
+      {
+#if defined(__AVR) || defined(ESP8266) || defined(ESP32)
+        data = pgm_read_byte(&black[idx]);
+#else
+        data = black[idx];
+#endif
+      }
+      else
+      {
+        data = black[idx];
+      }
+      if (invert) data = ~data;
+      _writeData(~data);
+    }
+  }
+  _setPartialRamArea_270c(0x15, x1, y1, w1, h1);
+  for (int16_t i = 0; i < h1; i++)
+  {
+    for (int16_t j = 0; j < w1 / 8; j++)
+    {
+      uint8_t data = 0xFF;
+      if (color)
+      {
+        // use wb_bitmap, h_bitmap of bitmap for index!
+        int16_t idx = mirror_y ? x_part / 8 + j + dx / 8 + ((h_bitmap - 1 - (y_part + i + dy))) * wb_bitmap : x_part / 8 + j + dx / 8 + (y_part + i + dy) * wb_bitmap;
+        if (pgm)
+        {
+#if defined(__AVR) || defined(ESP8266) || defined(ESP32)
+          data = pgm_read_byte(&color[idx]);
+#else
+          data = color[idx];
+#endif
+        }
+        else
+        {
+          data = color[idx];
+        }
+        if (invert) data = ~data;
+      }
+      _writeData(~data);
+    }
+  }
+  delay(1); // yield() to avoid WDT on ESP8266 and ESP32
+}
+
 void GxEPD2_270c::writeNative(const uint8_t* data1, const uint8_t* data2, int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
 {
   if (data1)
@@ -150,12 +233,26 @@ void GxEPD2_270c::drawImage(const uint8_t bitmap[], int16_t x, int16_t y, int16_
   refresh(x, y, w, h);
 }
 
+void GxEPD2_270c::drawImagePart(const uint8_t bitmap[], int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                                int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
+{
+  writeImagePart(bitmap, x_part, y_part, w_bitmap, h_bitmap, x, y, w, h, invert, mirror_y, pgm);
+  refresh(x, y, w, h);
+}
+
 void GxEPD2_270c::drawImage(const uint8_t* black, const uint8_t* color, int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
 {
   writeImage(black, color, x, y, w, h, invert, mirror_y, pgm);
   refresh(x, y, w, h);
 }
 
+void GxEPD2_270c::drawImagePart(const uint8_t* black, const uint8_t* color, int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                                int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
+{
+  writeImagePart(black, color, x_part, y_part, w_bitmap, h_bitmap, x, y, w, h, invert, mirror_y, pgm);
+  refresh(x, y, w, h);
+}
+
 void GxEPD2_270c::drawNative(const uint8_t* data1, const uint8_t* data2, int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
 {
   writeNative(data1, data2, x, y, w, h, invert, mirror_y, pgm);

src/epd3c/GxEPD2_270c.h

@@ -39,12 +39,20 @@ class GxEPD2_270c : public GxEPD2_EPD
     void writeScreenBuffer(uint8_t black_value, uint8_t color_value); // init controller memory
     // write to controller memory, without screen refresh; x and w should be multiple of 8
     void writeImage(const uint8_t bitmap[], int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
+    void writeImagePart(const uint8_t bitmap[], int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                        int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     void writeImage(const uint8_t* black, const uint8_t* color, int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
+    void writeImagePart(const uint8_t* black, const uint8_t* color, int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                        int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     // write sprite of native data to controller memory, without screen refresh; x and w should be multiple of 8
     void writeNative(const uint8_t* data1, const uint8_t* data2, int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     // write to controller memory, with screen refresh; x and w should be multiple of 8
     void drawImage(const uint8_t bitmap[], int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
+    void drawImagePart(const uint8_t bitmap[], int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                       int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     void drawImage(const uint8_t* black, const uint8_t* color, int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
+    void drawImagePart(const uint8_t* black, const uint8_t* color, int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                       int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     // write sprite of native data to controller memory, with screen refresh; x and w should be multiple of 8
     void drawNative(const uint8_t* data1, const uint8_t* data2, int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     void refresh(bool partial_update_mode = false); // screen refresh from controller memory to full screen

src/epd3c/GxEPD2_290c.cpp

@@ -146,6 +146,92 @@ void GxEPD2_290c::writeImage(const uint8_t* black, const uint8_t* color, int16_t
   delay(1); // yield() to avoid WDT on ESP8266 and ESP32
 }
 
+void GxEPD2_290c::writeImagePart(const uint8_t bitmap[], int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                                 int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
+{
+  writeImagePart(bitmap, NULL, x_part, y_part, w_bitmap, h_bitmap, x, y, w, h, invert, mirror_y, pgm);
+}
+
+void GxEPD2_290c::writeImagePart(const uint8_t* black, const uint8_t* color, int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                                 int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
+{
+  delay(1); // yield() to avoid WDT on ESP8266 and ESP32
+  if ((w_bitmap < 0) || (h_bitmap < 0) || (w < 0) || (h < 0)) return;
+  if ((x_part < 0) || (x_part >= w_bitmap)) return;
+  if ((y_part < 0) || (y_part >= h_bitmap)) return;
+  int16_t wb_bitmap = (w_bitmap + 7) / 8; // width bytes, bitmaps are padded
+  x_part -= x_part % 8; // byte boundary
+  w = w_bitmap - x_part < w ? w_bitmap - x_part : w; // limit
+  h = h_bitmap - y_part < h ? h_bitmap - y_part : h; // limit
+  x -= x % 8; // byte boundary
+  w = 8 * ((w + 7) / 8); // byte boundary, bitmaps are padded
+  int16_t x1 = x < 0 ? 0 : x; // limit
+  int16_t y1 = y < 0 ? 0 : y; // limit
+  int16_t w1 = x + w < int16_t(WIDTH) ? w : int16_t(WIDTH) - x; // limit
+  int16_t h1 = y + h < int16_t(HEIGHT) ? h : int16_t(HEIGHT) - y; // limit
+  int16_t dx = x1 - x;
+  int16_t dy = y1 - y;
+  w1 -= dx;
+  h1 -= dy;
+  if ((w1 <= 0) || (h1 <= 0)) return;
+  if (!_using_partial_mode) _Init_Part();
+  _writeCommand(0x91); // partial in
+  _setPartialRamArea(x1, y1, w1, h1);
+  _writeCommand(0x10);
+  for (int16_t i = 0; i < h1; i++)
+  {
+    for (int16_t j = 0; j < w1 / 8; j++)
+    {
+      uint8_t data;
+      // use wb_bitmap, h_bitmap of bitmap for index!
+      int16_t idx = mirror_y ? x_part / 8 + j + dx / 8 + ((h_bitmap - 1 - (y_part + i + dy))) * wb_bitmap : x_part / 8 + j + dx / 8 + (y_part + i + dy) * wb_bitmap;
+      if (pgm)
+      {
+#if defined(__AVR) || defined(ESP8266) || defined(ESP32)
+        data = pgm_read_byte(&black[idx]);
+#else
+        data = black[idx];
+#endif
+      }
+      else
+      {
+        data = black[idx];
+      }
+      if (invert) data = ~data;
+      _writeData(data);
+    }
+  }
+  _writeCommand(0x13);
+  for (int16_t i = 0; i < h1; i++)
+  {
+    for (int16_t j = 0; j < w1 / 8; j++)
+    {
+      uint8_t data = 0xFF;
+      if (color)
+      {
+        // use wb_bitmap, h_bitmap of bitmap for index!
+        int16_t idx = mirror_y ? x_part / 8 + j + dx / 8 + ((h_bitmap - 1 - (y_part + i + dy))) * wb_bitmap : x_part / 8 + j + dx / 8 + (y_part + i + dy) * wb_bitmap;
+        if (pgm)
+        {
+#if defined(__AVR) || defined(ESP8266) || defined(ESP32)
+          data = pgm_read_byte(&color[idx]);
+#else
+          data = color[idx];
+#endif
+        }
+        else
+        {
+          data = color[idx];
+        }
+        if (invert) data = ~data;
+      }
+      _writeData(data);
+    }
+  }
+  _writeCommand(0x92); // partial out
+  delay(1); // yield() to avoid WDT on ESP8266 and ESP32
+}
+
 void GxEPD2_290c::writeNative(const uint8_t* data1, const uint8_t* data2, int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
 {
   if (data1)
@@ -160,12 +246,26 @@ void GxEPD2_290c::drawImage(const uint8_t bitmap[], int16_t x, int16_t y, int16_
   refresh(x, y, w, h);
 }
 
+void GxEPD2_290c::drawImagePart(const uint8_t bitmap[], int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                                int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
+{
+  writeImagePart(bitmap, x_part, y_part, w_bitmap, h_bitmap, x, y, w, h, invert, mirror_y, pgm);
+  refresh(x, y, w, h);
+}
+
 void GxEPD2_290c::drawImage(const uint8_t* black, const uint8_t* color, int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
 {
   writeImage(black, color, x, y, w, h, invert, mirror_y, pgm);
   refresh(x, y, w, h);
 }
 
+void GxEPD2_290c::drawImagePart(const uint8_t* black, const uint8_t* color, int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                                int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
+{
+  writeImagePart(black, color, x_part, y_part, w_bitmap, h_bitmap, x, y, w, h, invert, mirror_y, pgm);
+  refresh(x, y, w, h);
+}
+
 void GxEPD2_290c::drawNative(const uint8_t* data1, const uint8_t* data2, int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
 {
   writeNative(data1, data2, x, y, w, h, invert, mirror_y, pgm);

src/epd3c/GxEPD2_290c.h

@@ -39,12 +39,20 @@ class GxEPD2_290c : public GxEPD2_EPD
     void writeScreenBuffer(uint8_t black_value, uint8_t color_value); // init controller memory
     // write to controller memory, without screen refresh; x and w should be multiple of 8
     void writeImage(const uint8_t bitmap[], int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
+    void writeImagePart(const uint8_t bitmap[], int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                        int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     void writeImage(const uint8_t* black, const uint8_t* color, int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
+    void writeImagePart(const uint8_t* black, const uint8_t* color, int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                        int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     // write sprite of native data to controller memory, without screen refresh; x and w should be multiple of 8
     void writeNative(const uint8_t* data1, const uint8_t* data2, int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     // write to controller memory, with screen refresh; x and w should be multiple of 8
     void drawImage(const uint8_t bitmap[], int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
+    void drawImagePart(const uint8_t bitmap[], int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                       int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     void drawImage(const uint8_t* black, const uint8_t* color, int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
+    void drawImagePart(const uint8_t* black, const uint8_t* color, int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                       int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     // write sprite of native data to controller memory, with screen refresh; x and w should be multiple of 8
     void drawNative(const uint8_t* data1, const uint8_t* data2, int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     void refresh(bool partial_update_mode = false); // screen refresh from controller memory to full screen

src/epd3c/GxEPD2_420c.cpp

@@ -146,6 +146,92 @@ void GxEPD2_420c::writeImage(const uint8_t* black, const uint8_t* color, int16_t
   delay(1); // yield() to avoid WDT on ESP8266 and ESP32
 }
 
+void GxEPD2_420c::writeImagePart(const uint8_t bitmap[], int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                                 int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
+{
+  writeImagePart(bitmap, NULL, x_part, y_part, w_bitmap, h_bitmap, x, y, w, h, invert, mirror_y, pgm);
+}
+
+void GxEPD2_420c::writeImagePart(const uint8_t* black, const uint8_t* color, int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                                 int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
+{
+  delay(1); // yield() to avoid WDT on ESP8266 and ESP32
+  if ((w_bitmap < 0) || (h_bitmap < 0) || (w < 0) || (h < 0)) return;
+  if ((x_part < 0) || (x_part >= w_bitmap)) return;
+  if ((y_part < 0) || (y_part >= h_bitmap)) return;
+  int16_t wb_bitmap = (w_bitmap + 7) / 8; // width bytes, bitmaps are padded
+  x_part -= x_part % 8; // byte boundary
+  w = w_bitmap - x_part < w ? w_bitmap - x_part : w; // limit
+  h = h_bitmap - y_part < h ? h_bitmap - y_part : h; // limit
+  x -= x % 8; // byte boundary
+  w = 8 * ((w + 7) / 8); // byte boundary, bitmaps are padded
+  int16_t x1 = x < 0 ? 0 : x; // limit
+  int16_t y1 = y < 0 ? 0 : y; // limit
+  int16_t w1 = x + w < int16_t(WIDTH) ? w : int16_t(WIDTH) - x; // limit
+  int16_t h1 = y + h < int16_t(HEIGHT) ? h : int16_t(HEIGHT) - y; // limit
+  int16_t dx = x1 - x;
+  int16_t dy = y1 - y;
+  w1 -= dx;
+  h1 -= dy;
+  if ((w1 <= 0) || (h1 <= 0)) return;
+  if (!_using_partial_mode) _Init_Part();
+  _writeCommand(0x91); // partial in
+  _setPartialRamArea(x1, y1, w1, h1);
+  _writeCommand(0x10);
+  for (int16_t i = 0; i < h1; i++)
+  {
+    for (int16_t j = 0; j < w1 / 8; j++)
+    {
+      uint8_t data;
+      // use wb_bitmap, h_bitmap of bitmap for index!
+      int16_t idx = mirror_y ? x_part / 8 + j + dx / 8 + ((h_bitmap - 1 - (y_part + i + dy))) * wb_bitmap : x_part / 8 + j + dx / 8 + (y_part + i + dy) * wb_bitmap;
+      if (pgm)
+      {
+#if defined(__AVR) || defined(ESP8266) || defined(ESP32)
+        data = pgm_read_byte(&black[idx]);
+#else
+        data = black[idx];
+#endif
+      }
+      else
+      {
+        data = black[idx];
+      }
+      if (invert) data = ~data;
+      _writeData(data);
+    }
+  }
+  _writeCommand(0x13);
+  for (int16_t i = 0; i < h1; i++)
+  {
+    for (int16_t j = 0; j < w1 / 8; j++)
+    {
+      uint8_t data = 0xFF;
+      if (color)
+      {
+        // use wb_bitmap, h_bitmap of bitmap for index!
+        int16_t idx = mirror_y ? x_part / 8 + j + dx / 8 + ((h_bitmap - 1 - (y_part + i + dy))) * wb_bitmap : x_part / 8 + j + dx / 8 + (y_part + i + dy) * wb_bitmap;
+        if (pgm)
+        {
+#if defined(__AVR) || defined(ESP8266) || defined(ESP32)
+          data = pgm_read_byte(&color[idx]);
+#else
+          data = color[idx];
+#endif
+        }
+        else
+        {
+          data = color[idx];
+        }
+        if (invert) data = ~data;
+      }
+      _writeData(data);
+    }
+  }
+  _writeCommand(0x92); // partial out
+  delay(1); // yield() to avoid WDT on ESP8266 and ESP32
+}
+
 void GxEPD2_420c::writeNative(const uint8_t* data1, const uint8_t* data2, int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
 {
   if (data1)
@@ -160,12 +246,26 @@ void GxEPD2_420c::drawImage(const uint8_t bitmap[], int16_t x, int16_t y, int16_
   refresh(x, y, w, h);
 }
 
+void GxEPD2_420c::drawImagePart(const uint8_t bitmap[], int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                                int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
+{
+  writeImagePart(bitmap, x_part, y_part, w_bitmap, h_bitmap, x, y, w, h, invert, mirror_y, pgm);
+  refresh(x, y, w, h);
+}
+
 void GxEPD2_420c::drawImage(const uint8_t* black, const uint8_t* color, int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
 {
   writeImage(black, color, x, y, w, h, invert, mirror_y, pgm);
   refresh(x, y, w, h);
 }
 
+void GxEPD2_420c::drawImagePart(const uint8_t* black, const uint8_t* color, int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                                int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
+{
+  writeImagePart(black, color, x_part, y_part, w_bitmap, h_bitmap, x, y, w, h, invert, mirror_y, pgm);
+  refresh(x, y, w, h);
+}
+
 void GxEPD2_420c::drawNative(const uint8_t* data1, const uint8_t* data2, int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
 {
   writeNative(data1, data2, x, y, w, h, invert, mirror_y, pgm);

src/epd3c/GxEPD2_420c.h

@@ -39,12 +39,20 @@ class GxEPD2_420c : public GxEPD2_EPD
     void writeScreenBuffer(uint8_t black_value, uint8_t color_value); // init controller memory
     // write to controller memory, without screen refresh; x and w should be multiple of 8
     void writeImage(const uint8_t bitmap[], int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
+    void writeImagePart(const uint8_t bitmap[], int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                        int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     void writeImage(const uint8_t* black, const uint8_t* color, int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
+    void writeImagePart(const uint8_t* black, const uint8_t* color, int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                        int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     // write sprite of native data to controller memory, without screen refresh; x and w should be multiple of 8
     void writeNative(const uint8_t* data1, const uint8_t* data2, int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     // write to controller memory, with screen refresh; x and w should be multiple of 8
     void drawImage(const uint8_t bitmap[], int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
+    void drawImagePart(const uint8_t bitmap[], int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                       int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     void drawImage(const uint8_t* black, const uint8_t* color, int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
+    void drawImagePart(const uint8_t* black, const uint8_t* color, int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                       int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     // write sprite of native data to controller memory, with screen refresh; x and w should be multiple of 8
     void drawNative(const uint8_t* data1, const uint8_t* data2, int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     void refresh(bool partial_update_mode = false); // screen refresh from controller memory to full screen

src/epd3c/GxEPD2_583c.cpp

@@ -81,7 +81,7 @@ void GxEPD2_583c::writeImage(const uint8_t bitmap[], int16_t x, int16_t y, int16
 void GxEPD2_583c::writeImage(const uint8_t* black, const uint8_t* color, int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
 {
   delay(1); // yield() to avoid WDT on ESP8266 and ESP32
-  int16_t wb = (w + 7) / 8; // width bytes, bitmaps are padded
+  uint16_t wb = (w + 7) / 8; // width bytes, bitmaps are padded
   x -= x % 8; // byte boundary
   w = wb * 8; // byte boundary
   int16_t x1 = x < 0 ? 0 : x; // limit
@@ -106,7 +106,7 @@ void GxEPD2_583c::writeImage(const uint8_t* black, const uint8_t* color, int16_t
       if (black)
       {
         // use wb, h of bitmap for index!
-        int16_t idx = mirror_y ? j + dx / 8 + ((h - 1 - (i + dy))) * wb : j + dx / 8 + (i + dy) * wb;
+        uint16_t idx = mirror_y ? j + dx / 8 + uint16_t((h - 1 - (i + dy))) * wb : j + dx / 8 + uint16_t(i + dy) * wb;
         if (pgm)
         {
 #if defined(__AVR) || defined(ESP8266) || defined(ESP32)
@@ -149,6 +149,88 @@ void GxEPD2_583c::writeImage(const uint8_t* black, const uint8_t* color, int16_t
   delay(1); // yield() to avoid WDT on ESP8266 and ESP32
 }
 
+void GxEPD2_583c::writeImagePart(const uint8_t bitmap[], int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                                 int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
+{
+  writeImagePart(bitmap, NULL, x_part, y_part, w_bitmap, h_bitmap, x, y, w, h, invert, mirror_y, pgm);
+}
+
+void GxEPD2_583c::writeImagePart(const uint8_t* black, const uint8_t* color, int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                                 int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
+{
+  delay(1); // yield() to avoid WDT on ESP8266 and ESP32
+  if ((w_bitmap < 0) || (h_bitmap < 0) || (w < 0) || (h < 0)) return;
+  if ((x_part < 0) || (x_part >= w_bitmap)) return;
+  if ((y_part < 0) || (y_part >= h_bitmap)) return;
+  uint16_t wb_bitmap = (w_bitmap + 7) / 8; // width bytes, bitmaps are padded
+  x_part -= x_part % 8; // byte boundary
+  w = w_bitmap - x_part < w ? w_bitmap - x_part : w; // limit
+  h = h_bitmap - y_part < h ? h_bitmap - y_part : h; // limit
+  x -= x % 8; // byte boundary
+  w = 8 * ((w + 7) / 8); // byte boundary, bitmaps are padded
+  int16_t x1 = x < 0 ? 0 : x; // limit
+  int16_t y1 = y < 0 ? 0 : y; // limit
+  int16_t w1 = x + w < int16_t(WIDTH) ? w : int16_t(WIDTH) - x; // limit
+  int16_t h1 = y + h < int16_t(HEIGHT) ? h : int16_t(HEIGHT) - y; // limit
+  int16_t dx = x1 - x;
+  int16_t dy = y1 - y;
+  w1 -= dx;
+  h1 -= dy;
+  if ((w1 <= 0) || (h1 <= 0)) return;
+  if (!_using_partial_mode) _Init_Part();
+  _writeCommand(0x91); // partial in
+  _setPartialRamArea(x1, y1, w1, h1);
+  _writeCommand(0x10);
+  for (int16_t i = 0; i < h1; i++)
+  {
+    for (int16_t j = 0; j < w1 / 8; j++)
+    {
+      uint8_t black_data = 0xFF;
+      uint8_t color_data = 0xFF;
+      // use wb_bitmap, h_bitmap of bitmap for index!
+      uint16_t idx = mirror_y ? x_part / 8 + j + dx / 8 + uint16_t((h_bitmap - 1 - (y_part + i + dy))) * wb_bitmap : x_part / 8 + j + dx / 8 + uint16_t(y_part + i + dy) * wb_bitmap;
+      if (black)
+      {
+        if (pgm)
+        {
+#if defined(__AVR) || defined(ESP8266) || defined(ESP32)
+          black_data = pgm_read_byte(&black[idx]);
+#else
+          black_data = black[idx];
+#endif
+        }
+        else
+        {
+          black_data = black[idx];
+        }
+        if (invert) black_data = ~black_data;
+      }
+      if (color)
+      {
+        if (pgm)
+        {
+#if defined(__AVR) || defined(ESP8266) || defined(ESP32)
+          color_data = pgm_read_byte(&color[idx]);
+#else
+          color_data = color[idx];
+#endif
+        }
+        else
+        {
+          color_data = color[idx];
+        }
+        if (invert) color_data = ~color_data;
+      }
+      _send8pixel(~black_data, ~color_data);
+    }
+#if defined(ESP8266)
+    yield();
+#endif
+  }
+  _writeCommand(0x92); // partial out
+  delay(1); // yield() to avoid WDT on ESP8266 and ESP32
+}
+
 void GxEPD2_583c::writeNative(const uint8_t* data1, const uint8_t* data2, int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
 {
   if (data1)
@@ -204,12 +286,26 @@ void GxEPD2_583c::drawImage(const uint8_t bitmap[], int16_t x, int16_t y, int16_
   refresh(x, y, w, h);
 }
 
+void GxEPD2_583c::drawImagePart(const uint8_t bitmap[], int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                                int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
+{
+  writeImagePart(bitmap, x_part, y_part, w_bitmap, h_bitmap, x, y, w, h, invert, mirror_y, pgm);
+  refresh(x, y, w, h);
+}
+
 void GxEPD2_583c::drawImage(const uint8_t* black, const uint8_t* color, int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
 {
   writeImage(black, color, x, y, w, h, invert, mirror_y, pgm);
   refresh(x, y, w, h);
 }
 
+void GxEPD2_583c::drawImagePart(const uint8_t* black, const uint8_t* color, int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                                int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
+{
+  writeImagePart(black, color, x_part, y_part, w_bitmap, h_bitmap, x, y, w, h, invert, mirror_y, pgm);
+  refresh(x, y, w, h);
+}
+
 void GxEPD2_583c::drawNative(const uint8_t* data1, const uint8_t* data2, int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
 {
   writeNative(data1, data2, x, y, w, h, invert, mirror_y, pgm);

src/epd3c/GxEPD2_583c.h

@@ -39,12 +39,20 @@ class GxEPD2_583c : public GxEPD2_EPD
     void writeScreenBuffer(uint8_t black_value, uint8_t red_value); // init controller memory
     // write to controller memory, without screen refresh; x and w should be multiple of 8
     void writeImage(const uint8_t bitmap[], int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
-    void writeImage(const uint8_t* black, const uint8_t* red, int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
+    void writeImagePart(const uint8_t bitmap[], int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                        int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
+    void writeImage(const uint8_t* black, const uint8_t* color, int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
+    void writeImagePart(const uint8_t* black, const uint8_t* color, int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                        int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     // write sprite of native data to controller memory, without screen refresh; x and w should be multiple of 8
     void writeNative(const uint8_t* data1, const uint8_t* data2, int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     // write to controller memory, with screen refresh; x and w should be multiple of 8
     void drawImage(const uint8_t bitmap[], int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
-    void drawImage(const uint8_t* black, const uint8_t* red, int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
+    void drawImagePart(const uint8_t bitmap[], int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                       int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
+    void drawImage(const uint8_t* black, const uint8_t* color, int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
+    void drawImagePart(const uint8_t* black, const uint8_t* color, int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                       int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     // write sprite of native data to controller memory, with screen refresh; x and w should be multiple of 8
     void drawNative(const uint8_t* data1, const uint8_t* data2, int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     void refresh(bool partial_update_mode = false); // screen refresh from controller memory to full screen

src/epd3c/GxEPD2_750c.cpp

@@ -81,7 +81,7 @@ void GxEPD2_750c::writeImage(const uint8_t bitmap[], int16_t x, int16_t y, int16
 void GxEPD2_750c::writeImage(const uint8_t* black, const uint8_t* color, int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
 {
   delay(1); // yield() to avoid WDT on ESP8266 and ESP32
-  int16_t wb = (w + 7) / 8; // width bytes, bitmaps are padded
+  uint16_t wb = (w + 7) / 8; // width bytes, bitmaps are padded
   x -= x % 8; // byte boundary
   w = wb * 8; // byte boundary
   int16_t x1 = x < 0 ? 0 : x; // limit
@@ -106,7 +106,7 @@ void GxEPD2_750c::writeImage(const uint8_t* black, const uint8_t* color, int16_t
       if (black)
       {
         // use wb, h of bitmap for index!
-        int16_t idx = mirror_y ? j + dx / 8 + ((h - 1 - (i + dy))) * wb : j + dx / 8 + (i + dy) * wb;
+        uint16_t idx = mirror_y ? j + dx / 8 + uint16_t((h - 1 - (i + dy))) * wb : j + dx / 8 + uint16_t(i + dy) * wb;
         if (pgm)
         {
 #if defined(__AVR) || defined(ESP8266) || defined(ESP32)
@@ -146,6 +146,88 @@ void GxEPD2_750c::writeImage(const uint8_t* black, const uint8_t* color, int16_t
   delay(1); // yield() to avoid WDT on ESP8266 and ESP32
 }
 
+void GxEPD2_750c::writeImagePart(const uint8_t bitmap[], int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                                 int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
+{
+  writeImagePart(bitmap, NULL, x_part, y_part, w_bitmap, h_bitmap, x, y, w, h, invert, mirror_y, pgm);
+}
+
+void GxEPD2_750c::writeImagePart(const uint8_t* black, const uint8_t* color, int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                                 int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
+{
+  delay(1); // yield() to avoid WDT on ESP8266 and ESP32
+  if ((w_bitmap < 0) || (h_bitmap < 0) || (w < 0) || (h < 0)) return;
+  if ((x_part < 0) || (x_part >= w_bitmap)) return;
+  if ((y_part < 0) || (y_part >= h_bitmap)) return;
+  uint16_t wb_bitmap = (w_bitmap + 7) / 8; // width bytes, bitmaps are padded
+  x_part -= x_part % 8; // byte boundary
+  w = w_bitmap - x_part < w ? w_bitmap - x_part : w; // limit
+  h = h_bitmap - y_part < h ? h_bitmap - y_part : h; // limit
+  x -= x % 8; // byte boundary
+  w = 8 * ((w + 7) / 8); // byte boundary, bitmaps are padded
+  int16_t x1 = x < 0 ? 0 : x; // limit
+  int16_t y1 = y < 0 ? 0 : y; // limit
+  int16_t w1 = x + w < int16_t(WIDTH) ? w : int16_t(WIDTH) - x; // limit
+  int16_t h1 = y + h < int16_t(HEIGHT) ? h : int16_t(HEIGHT) - y; // limit
+  int16_t dx = x1 - x;
+  int16_t dy = y1 - y;
+  w1 -= dx;
+  h1 -= dy;
+  if ((w1 <= 0) || (h1 <= 0)) return;
+  if (!_using_partial_mode) _Init_Part();
+  _writeCommand(0x91); // partial in
+  _setPartialRamArea(x1, y1, w1, h1);
+  _writeCommand(0x10);
+  for (int16_t i = 0; i < h1; i++)
+  {
+    for (int16_t j = 0; j < w1 / 8; j++)
+    {
+      uint8_t black_data = 0xFF;
+      uint8_t color_data = 0xFF;
+      // use wb_bitmap, h_bitmap of bitmap for index!
+      uint16_t idx = mirror_y ? x_part / 8 + j + dx / 8 + uint16_t((h_bitmap - 1 - (y_part + i + dy))) * wb_bitmap : x_part / 8 + j + dx / 8 + uint16_t(y_part + i + dy) * wb_bitmap;
+      if (black)
+      {
+        if (pgm)
+        {
+#if defined(__AVR) || defined(ESP8266) || defined(ESP32)
+          black_data = pgm_read_byte(&black[idx]);
+#else
+          black_data = black[idx];
+#endif
+        }
+        else
+        {
+          black_data = black[idx];
+        }
+        if (invert) black_data = ~black_data;
+      }
+      if (color)
+      {
+        if (pgm)
+        {
+#if defined(__AVR) || defined(ESP8266) || defined(ESP32)
+          color_data = pgm_read_byte(&color[idx]);
+#else
+          color_data = color[idx];
+#endif
+        }
+        else
+        {
+          color_data = color[idx];
+        }
+        if (invert) color_data = ~color_data;
+      }
+      _send8pixel(~black_data, ~color_data);
+    }
+#if defined(ESP8266)
+    yield();
+#endif
+  }
+  _writeCommand(0x92); // partial out
+  delay(1); // yield() to avoid WDT on ESP8266 and ESP32
+}
+
 void GxEPD2_750c::writeNative(const uint8_t* data1, const uint8_t* data2, int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
 {
   if (data1)
@@ -201,12 +283,26 @@ void GxEPD2_750c::drawImage(const uint8_t bitmap[], int16_t x, int16_t y, int16_
   refresh(x, y, w, h);
 }
 
+void GxEPD2_750c::drawImagePart(const uint8_t bitmap[], int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                                int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
+{
+  writeImagePart(bitmap, x_part, y_part, w_bitmap, h_bitmap, x, y, w, h, invert, mirror_y, pgm);
+  refresh(x, y, w, h);
+}
+
 void GxEPD2_750c::drawImage(const uint8_t* black, const uint8_t* color, int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
 {
   writeImage(black, color, x, y, w, h, invert, mirror_y, pgm);
   refresh(x, y, w, h);
 }
 
+void GxEPD2_750c::drawImagePart(const uint8_t* black, const uint8_t* color, int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                                int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
+{
+  writeImagePart(black, color, x_part, y_part, w_bitmap, h_bitmap, x, y, w, h, invert, mirror_y, pgm);
+  refresh(x, y, w, h);
+}
+
 void GxEPD2_750c::drawNative(const uint8_t* data1, const uint8_t* data2, int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
 {
   writeNative(data1, data2, x, y, w, h, invert, mirror_y, pgm);

src/epd3c/GxEPD2_750c.h

@@ -39,12 +39,20 @@ class GxEPD2_750c : public GxEPD2_EPD
     void writeScreenBuffer(uint8_t black_value, uint8_t red_value); // init controller memory
     // write to controller memory, without screen refresh; x and w should be multiple of 8
     void writeImage(const uint8_t bitmap[], int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
-    void writeImage(const uint8_t* black, const uint8_t* red, int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
+    void writeImagePart(const uint8_t bitmap[], int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                        int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
+    void writeImage(const uint8_t* black, const uint8_t* color, int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
+    void writeImagePart(const uint8_t* black, const uint8_t* color, int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                        int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     // write sprite of native data to controller memory, without screen refresh; x and w should be multiple of 8
     void writeNative(const uint8_t* data1, const uint8_t* data2, int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     // write to controller memory, with screen refresh; x and w should be multiple of 8
     void drawImage(const uint8_t bitmap[], int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
-    void drawImage(const uint8_t* black, const uint8_t* red, int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
+    void drawImagePart(const uint8_t bitmap[], int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                       int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
+    void drawImage(const uint8_t* black, const uint8_t* color, int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
+    void drawImagePart(const uint8_t* black, const uint8_t* color, int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                       int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     // write sprite of native data to controller memory, with screen refresh; x and w should be multiple of 8
     void drawNative(const uint8_t* data1, const uint8_t* data2, int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     void refresh(bool partial_update_mode = false); // screen refresh from controller memory to full screen

src/it8951/GxEPD2_it60.cpp

@@ -210,6 +210,64 @@ void GxEPD2_it60::writeImage(const uint8_t bitmap[], int16_t x, int16_t y, int16
   delay(1); // yield() to avoid WDT on ESP8266 and ESP32
 }
 
+void GxEPD2_it60::writeImagePart(const uint8_t bitmap[], int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                                int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
+{
+  delay(1); // yield() to avoid WDT on ESP8266 and ESP32
+  if ((w_bitmap < 0) || (h_bitmap < 0) || (w < 0) || (h < 0)) return;
+  if ((x_part < 0) || (x_part >= w_bitmap)) return;
+  if ((y_part < 0) || (y_part >= h_bitmap)) return;
+  int16_t wb_bitmap = (w_bitmap + 7) / 8; // width bytes, bitmaps are padded
+  x_part -= x_part % 8; // byte boundary
+  w = w_bitmap - x_part < w ? w_bitmap - x_part : w; // limit
+  h = h_bitmap - y_part < h ? h_bitmap - y_part : h; // limit
+  x -= x % 8; // byte boundary
+  w = 8 * ((w + 7) / 8); // byte boundary, bitmaps are padded
+  int16_t x1 = x < 0 ? 0 : x; // limit
+  int16_t y1 = y < 0 ? 0 : y; // limit
+  int16_t w1 = x + w < int16_t(WIDTH) ? w : int16_t(WIDTH) - x; // limit
+  int16_t h1 = y + h < int16_t(HEIGHT) ? h : int16_t(HEIGHT) - y; // limit
+  int16_t dx = x1 - x;
+  int16_t dy = y1 - y;
+  w1 -= dx;
+  h1 -= dy;
+  if ((w1 <= 0) || (h1 <= 0)) return;
+  if (!_using_partial_mode) _Init_Part();
+  _setPartialRamArea(x1, y1, w1, h1);
+  SPI.beginTransaction(_spi_settings);
+  if (_cs >= 0) digitalWrite(_cs, LOW);
+  _transfer16(0x0000); // preamble for write data
+  _waitWhileBusy2("writeImage preamble", default_wait_time);
+  for (int16_t i = 0; i < h1; i++)
+  {
+    for (int16_t j = 0; j < w1 / 8; j++)
+    {
+      uint8_t data;
+      // use wb_bitmap, h_bitmap of bitmap for index!
+      int16_t idx = mirror_y ? x_part / 8 + j + dx / 8 + ((h_bitmap - 1 - (y_part + i + dy))) * wb_bitmap : x_part / 8 + j + dx / 8 + (y_part + i + dy) * wb_bitmap;
+      if (pgm)
+      {
+#if defined(__AVR) || defined(ESP8266) || defined(ESP32)
+        data = pgm_read_byte(&bitmap[idx]);
+#else
+        data = bitmap[idx];
+#endif
+      }
+      else
+      {
+        data = bitmap[idx];
+      }
+      if (invert) data = ~data;
+      _send8pixel(~data);
+    }
+  }
+  if (_cs >= 0) digitalWrite(_cs, HIGH);
+  SPI.endTransaction();
+  _writeCommand16(IT8951_TCON_LD_IMG_END);
+  _waitWhileBusy2("writeImage load end", default_wait_time);
+  delay(1); // yield() to avoid WDT on ESP8266 and ESP32
+}
+
 void GxEPD2_it60::writeImage(const uint8_t* black, const uint8_t* color, int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
 {
   if (black)
@@ -218,6 +276,15 @@ void GxEPD2_it60::writeImage(const uint8_t* black, const uint8_t* color, int16_t
   }
 }
 
+void GxEPD2_it60::writeImagePart(const uint8_t* black, const uint8_t* color, int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                                int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
+{
+  if (black)
+  {
+    writeImagePart(black, x_part, y_part, w_bitmap, h_bitmap, x, y, w, h, invert, mirror_y, pgm);
+  }
+}
+
 void GxEPD2_it60::writeNative(const uint8_t* data1, const uint8_t* data2, int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
 {
   if (data1)
@@ -278,12 +345,26 @@ void GxEPD2_it60::drawImage(const uint8_t bitmap[], int16_t x, int16_t y, int16_
   _refresh(x, y, w, h, true);
 }
 
+void GxEPD2_it60::drawImagePart(const uint8_t bitmap[], int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                               int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
+{
+  writeImagePart(bitmap, x_part, y_part, w_bitmap, h_bitmap, x, y, w, h, invert, mirror_y, pgm);
+  _refresh(x, y, w, h, true);
+}
+
 void GxEPD2_it60::drawImage(const uint8_t* black, const uint8_t* color, int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
 {
   writeImage(black, color, x, y, w, h, invert, mirror_y, pgm);
   _refresh(x, y, w, h, true);
 }
 
+void GxEPD2_it60::drawImagePart(const uint8_t* black, const uint8_t* color, int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                               int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
+{
+  writeImagePart(black, color, x_part, y_part, w_bitmap, h_bitmap, x, y, w, h, invert, mirror_y, pgm);
+  _refresh(x, y, w, h, true);
+}
+
 void GxEPD2_it60::drawNative(const uint8_t* data1, const uint8_t* data2, int16_t x, int16_t y, int16_t w, int16_t h, bool invert, bool mirror_y, bool pgm)
 {
   writeNative(data1, data2, x, y, w, h, invert, mirror_y, pgm);

src/it8951/GxEPD2_it60.h

@@ -49,12 +49,20 @@ class GxEPD2_it60 : public GxEPD2_EPD
     void writeScreenBuffer(uint8_t value = 0x33); // init controller memory (default white)
     // write to controller memory, without screen refresh; x and w should be multiple of 8
     void writeImage(const uint8_t bitmap[], int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
+    void writeImagePart(const uint8_t bitmap[], int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                        int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     void writeImage(const uint8_t* black, const uint8_t* color, int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
+    void writeImagePart(const uint8_t* black, const uint8_t* color, int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                        int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     // write sprite of native data to controller memory, without screen refresh; x and w should be multiple of 8
     void writeNative(const uint8_t* data1, const uint8_t* data2, int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     // write to controller memory, with screen refresh; x and w should be multiple of 8
     void drawImage(const uint8_t bitmap[], int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
+    void drawImagePart(const uint8_t bitmap[], int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                       int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     void drawImage(const uint8_t* black, const uint8_t* color, int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
+    void drawImagePart(const uint8_t* black, const uint8_t* color, int16_t x_part, int16_t y_part, int16_t w_bitmap, int16_t h_bitmap,
+                       int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     // write sprite of native data to controller memory, with screen refresh; x and w should be multiple of 8
     void drawNative(const uint8_t* data1, const uint8_t* data2, int16_t x, int16_t y, int16_t w, int16_t h, bool invert = false, bool mirror_y = false, bool pgm = false);
     void refresh(bool partial_update_mode = false); // screen refresh from controller memory to full screen