Network protocol used by GfxTablet



Version 1
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GfxTablet app sends UDP packets to port 40118 of the destination host.

Packet structure:

  9  octets   "GfxTablet"
  1  ushort   version number
  1  ushort   type:
              0 motion event (hovering)
              1 button event (finger, pen etc. touches surface)

  1  ushort   x (using full range: 0..65535)
  1  ushort   y (using full range: 0..65535)
  1  ushort   pressure (using full range 0..65535, 32768 == pressure 1.0f on Android device)

when type == button event:
  1  byte     number of button, starting with 0
  1  byte     button status:
              0 button is down
              1 button is up