CompuServe Messages

If your solid object has some polygons that are facing the inside, enabling the render backface button will make a world of difference. For example, if you have a sphere in which all the normals are reversed (facing the center of the sphere), the rendered object appears to be convace from the camera's viewpoint. This is because the polygons closest to the camera a facing away from it, so they aren't rendered: instead we're seeing the inside of the back half of the sphere. Enable Render Backface and both "sides" of a polygon are rendered: now the object appears convex becasue the polygons closest to the camera are being rendered. Render backface solves backface issues, but with a price: rendering time is a little slower, and shiny materials may show highlight "halos" on the "horizon" of the object being rendered with Render Backface enabled. Which brings me to the Normals Toolbox. This allows you to choose polygons and reverse object normals, should those normals be facing in the wrong direction. This reverses the direction in which polygons are facing. The Normals Toolbox is powerful and useful, but as you may have learned through experience in the Select Toolbox, picking polygons can require some practice. I have to refer you to Tutor 10 in the Renderize Live manual that comes with Visual Reality. Thus in short, the easy way to deal with reversed polynormals is to Render Backface; the best way is to reverse the normals of the culprit polygons. Nick Josephs Visual Software