diff --git a/panda/src/grutil/CMakeLists.txt b/panda/src/grutil/CMakeLists.txt
index 1324beea89..d7d2dd44ce 100644
--- a/panda/src/grutil/CMakeLists.txt
+++ b/panda/src/grutil/CMakeLists.txt
@@ -27,6 +27,7 @@ set(P3GRUTIL_SOURCES
   geoMipTerrain.cxx
   sceneGraphAnalyzerMeter.cxx
   heightfieldTesselator.cxx
+  multitexReducer.cxx
   nodeVertexTransform.cxx
   pfmVizzer.cxx
   pipeOcclusionCullTraverser.cxx