First draft of a DMX mixer. Still needs a socket to drive state changes (and a test util to drive the socket)

dmx/dmx.pl

@@ -0,0 +1,70 @@
+#!/usr/bin/python
+import os
+import sys
+import array
+import string
+from ola.ClientWrapper import ClientWrapper
+
+# ====================================
+# Globals
+# ====================================
+wrapper = None
+state = [ 0 ]
+cmds = { 'value' : [ 0 ], 'ticks' : [ 0 ] }
+sock = None
+
+# ====================================
+# Wrapper callback -- exit on errors
+# ====================================
+def DmxSent(state):
+  # Stop on errors
+  if not state.Succeeded():
+    wrapper.Stop()
+
+# ====================================
+# Main calculation
+# ====================================
+def SendDMXFrame():
+  # Re-schedule ourselves in interval ms (do this first to keep the timing consistent)
+  wrapper.AddEvent(interval, SendDMXFrame)
+
+  # Check for new commands
+  global sock
+  
+  # Update values for each channel
+  for i in range(len(cmds['value'])):
+    if (cmds['value'][i] != state[i]):
+      diff = cmds['value'][i] - state[i]
+      delta = float(diff) / float(cmds['ticks'][i])
+      state[i] += int(delta)
+      cmd['ticks'][i] -= 1
+  
+  # Send all DMX channels
+  data = array.array('B')
+  for i in range(len(state)):
+	data.append(state[i])
+  wrapper.Client().SendDmx(universe, data, DmxSent)
+
+# ====================================
+# Main
+# ====================================
+
+# Pick a universe (0, or as specified in the environment)
+universe = 0
+if 'UNIVERSE' in os.environ:
+  universe = int(os.environ['UNIVERSE'])
+
+# Pick a tick interval (50ms, or as specified in the environment)
+interval = 50
+if 'INTERVAL' in os.environ:
+  universe = int(os.environ['INTERVAL'])
+
+# Pick a socket file ($TMPDIR/plexMonitor/DMX.socket, or as specified in the environment)
+cmd_file = 'plexMonitor/DMX.socket'
+
+# Open the socket
+
+# Start the DMX loop
+wrapper = ClientWrapper()
+wrapper.AddEvent(interval, SendDMXFrame)
+wrapper.Run()