Resource packs

Iris Shader Compile Error: Undefined Variable iris_vertexColor in Entities Alpha

What it looks like in the log

java.io.IOException: Couldn't compile fragment program (<iris shaderpack shaders>, entities_alpha) : 0(78) : error C1503: undefined variable "iris_ver

How to fix it

  1. Update Iris Shaders (or Oculus if playing on Forge/NeoForge) to the latest version available for your Minecraft version, as this geometry shader attribute bug was patched in newer releases.
  2. Update your shaderpack to its newest version in case the pack author added an Iris compatibility workaround.
  3. If no newer version of Iris is available for your Minecraft version, switch to a different shaderpack that does not use geometry shaders for entities.
  4. If you are developing the shaderpack, remove or disable gbuffers_entities.gsh when running on older Iris versions.
LoadersFabric, Quilt, Forge, Neoforge
SeverityBreaks something
CategoryResource packs

Check your own log

Related errors

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