anchor.diff:  
     List colors; // one-to-one vertex colors, used in ParticleSystem, Line and Ribbon
     List materials;
  -  List faces;
  +  List<Face> faces;
   
     List faceUvs;
     List<List> faceVertexUvs;
  
positive.code:       vertices = __tmpVertices;
  
        faces.forEach((face) {
  
          if ( face is Face3 ) {
            face.vertexNormals = [ new Vector3.zero(), new Vector3.zero(), new Vector3.zero() ];
  
          } else if ( face is Face4 ) {
            face.vertexNormals = [ new Vector3.zero(), new Vector3.zero(), new Vector3.zero(), new Vector3.zero() ];
          }
        });
  
      } else {
  
negative.code:         }*/
  
        }
      });
  
      // Use unique set of vertices
      var diff = vertices.length - unique.length;
  