CompuServe Messages

Info Needed

    19-Apr-94 09:52:01
Sb: #97723-Info Needed
To: DAVE WATT 70033,3114
Dave: >> Be aware that the .DXF format does not define what is the "outside" >> surface. This of course is done in 3DS by assigning a "normal" to one >> side of a face… Well, yes and no! <g> There is no "inside" or "outside" of any face defined, but every face has a normal (or in some cases an abnormal, but that depends on your model! <g>) If you remember the "right hand rule" from high school, that will determine which way the normal is facing. 3DS renders every face which has the normal facing the camera, and ignores the others unless you have "force 2 sided" rendering turned on or assign a 2 sided material to the object in question. Your response was basically correct, I just wanted to clarify why! Greg Pyros