GLSL guide?

Hi, wanted to learn how to create 2D filters for the blender game engine, but don´t really know were to start. If someone that actually knows were to start can give me some refs i would apreciate that

Leaping into GLSL is pretty hard. I don’t touch it if I can help it (which is a lot of the time).

Things to realize:

  • It’s based on C++, so you have structs, classes, functions etc.
  • GLSL is generic, not blender-specific
  • Disect simple examples, for example, looking at martinsh’s DOF filter allowed me to write a mist shader.
  • Play with nodes. Things like mixing, adding and subtracting images are all done in GLSL, and having an idea about what they do is immensely useful.