Iris Patcher

The code contained in a shader pack is not the final code that is compiled and executed. In order to ensure maximum compatibility, Iris runs the shader code through glsl-transformer, which generates patched shader code. This is the code that actually ends up on the GPU. In the context of developing shaders, there are several important consequences to note:

• Since the patcher removes non-necessary whitespace in the code, line numbers in errors will not match up with the line numbers in your code
• You cannot name your functions or variables in a similar manner as internal Iris variables:
  • iris_
  • irisMain
  • moj_import
• The patcher will sometimes fix code that should otherwise fail
• Conversely, the patcher may not be flawless. If you’re experiencing a bug and have exhausted all other possibilites, its worth checking the patched shader code

Tip

When debug mode is enabled, the patched shader code can be found in the /patched_shaders/ folder in the root of your Minecraft directory.

More information can be found here.