diff --git a/src/SceneGraph/InlineGeometry.cpp b/src/SceneGraph/InlineGeometry.cpp
index c634593d..b35b3016 100644
--- a/src/SceneGraph/InlineGeometry.cpp
+++ b/src/SceneGraph/InlineGeometry.cpp
@@ -421,9 +421,9 @@ namespace hgl
             AutoDelete<VB2f> tex_coord=rc.CreateVADA<VB2f>(VAN::TexCoord);
 
             float *vp=vertex->Get();
-            float *np=normal->Get();
-            float *tp=tangent->Get();
-            float *tcp=tex_coord->Get();
+            float *np=normal?normal->Get():nullptr;
+            float *tp=tangent?tangent->Get():nullptr;
+            float *tcp=tex_coord?tex_coord->Get():nullptr;
 
             for (uint i = 0; i < numberParallels + 1; i++)
             {