diff --git a/wrap/gl/glu_tessellator_cap.h b/wrap/gl/glu_tessellator_cap.h
index c28a1d60..28b21bb2 100644
--- a/wrap/gl/glu_tessellator_cap.h
+++ b/wrap/gl/glu_tessellator_cap.h
@@ -18,7 +18,7 @@ void CapEdgeMesh(MeshType &em, MeshType &cm)
   UpdateFlags<MeshType>::EdgeClearV(em);
   UpdateTopology<MeshType>::EdgeEdge(em);
   int nv=0;
-  for(size_t i=0;i<em.edge.size();i++)
+  for(size_t i=0;i<em.edge.size();i++) if(!em.edge[i].IsD())
   {
     if (!em.edge[i].IsV())
     {