fix for objects do not have faceVertexUVs
fix for objects do not have faceVertexUVs

Makio64/ThreeCSG,Wilt/ThreeCSG,chandlerprall/ThreeCSG,magneval/ThreeCSG,elmarquez/ThreeCSG,lucidogen/ThreeCSG,lucidogen/ThreeCSG,koreldan/ThreeCSG,chandlerprall/ThreeCSG,Makio64/ThreeCSG,magneval/ThreeCSG,koreldan/ThreeCSG