Just like in the real world you are limited to what you can see in the expanding pyramid from your eyes. For instance if you move your hand from in front of you to the side without moving your head, at some point your hand will become invisible. Likewise if a wall is in front of you the object behind it are gone from your view, but one of the first things we learn in childhood is that the object is still there. This is the lesson we have finally taught the computer in creating our 3D worlds. Now the computer needs to determines what is the camera's visible area.
Clipping means simply that the polygons out of view are removed.
Once removed they will not be calculated through the rest of the 3D-Pipeline. This means that you will be determining their color based on the texture maps, while applying some form of filtering. The perspective is corrected and anti-aliasing is added to smooth the image and remove imperfections. Explaining how all this works would be too complex for this essay, but suffice it to say that the many factors are used depending on what settings have been made in the game and what features the 3D card supports. Shading Until now the light sources were not used in the calculations.