diff --git a/CMakeLists.txt b/CMakeLists.txt
index 5ce9dcc5..9b1a6c67 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -113,6 +113,7 @@ add_library(lego1 SHARED
   LEGO1/mxcontrolpresenter.cpp
   LEGO1/mxcore.cpp
   LEGO1/mxcriticalsection.cpp
+  LEGO1/mxdirect3d.cpp
   LEGO1/mxdirectdraw.cpp
   LEGO1/mxdiskstreamcontroller.cpp
   LEGO1/mxdiskstreamprovider.cpp