diff --git a/panda/src/grutil/multitexReducer.cxx b/panda/src/grutil/multitexReducer.cxx
index 2fff484de3..fd94e1d173 100644
--- a/panda/src/grutil/multitexReducer.cxx
+++ b/panda/src/grutil/multitexReducer.cxx
@@ -714,6 +714,7 @@ make_texture_layer(const NodePath &render,
   case TextureStage::M_height:
   case TextureStage::M_selector:
   case TextureStage::M_normal_gloss:
+  case TextureStage::M_emission:
     // Don't know what to do with these funny modes.  We should probably raise
     // an exception or something.  Fall through for now.