Last week I promised to explain how to perform hidden surface removal in a 3D engine. For a simple object rendering engine this only means that the image quality gets better, because your wireframe cubes become solid all of a sudden, for huge worlds it means that there is no limit on the size of a world, if you do it right.
Lets start with some stuff for the wireframe dudes.
For hidden surface removal, you need polygons. That way, you can attach a plane equation to your polygons, wich can in turn be used to detect wich way a polygon is oriented. In the case of the cube, it's easy to see that at least three of the polygons are not facing the camera, sometimes only a single polygon is visible. This is of course an easy way to ditch huge amounts of polygons. Of course, you only calculate this sphere once, or once for every frame in an object animation if neccessary.