Resource packs

Iris Warning: Unknown variable BIOME_* When Resolving Custom Uniforms

What it looks like in the log

java.lang.RuntimeException: Unknown variable: BIOME_SULFUR_CAVES

How to fix it

  1. If your game is still running, you can safely ignore this warning; if your game actually crashed, scroll to the bottom of latest.log or check the crash-reports folder for the real ERROR or FATAL cause.
  2. Update both Iris Shaders (switching off beta builds if a stable release is available) and your shader pack in the shaderpacks folder to the latest versions compatible with your exact Minecraft version.
  3. If you get this log spam while playing without shaders enabled, open Options -> Video Settings -> Shader Packs (or edit config/iris.properties) and clear the selected shaderPack entry so Iris stops parsing its custom uniforms.
  4. If you edit shader packs yourself, remove references to missing BIOME_* constants in the pack's shaders.properties file when targeting older Minecraft versions or modpacks without those biome mods.
LoadersNeoforge, Fabric, Quilt
SeverityWorth checking
CategoryResource packs

Check your own log

Related errors

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