CompuServe Messages

Tom, Another problem that can occur is mesh mismatches where various surfaces meet up. If you are building 3D objects from multiple surfaces/volumes, when AutoCAD converts the volumes to mesh surfaces it often doesn't check that adjacent surfaces have matching vertices. This is a common problem on things like ball-fillets. AutoCAD treats each edge fillet and the corner ball fillet as separate surfaces. When it meshes them you can get "T" intersections instead of the proper "X" intersections between meshes. The result is dark streaks on smooth surfaces. This can also confuse 3DS when it has to calculate surface normals for things like object-unify and boolean operations. Terry Gilbert Forcade & Associates