The emission file mask is an image that AGE of joy uses to create a lighting effect in a cabinet part.

CDL the Cabinet Description Language example:

- name: joystick
    art:
      file: joystick.png
      inverty: true
      invertx: true
    emission:
      emissive: true
      color:
        r: 255
        g: 255
        b: 255
      art:
        file: joystick_emission.png
        inverty: true
        invertx: true
joystick.pngjoystick_emission.pngfinal result

![note] You can turn on / off the emission and change the emission color using AGEBasic programing