ABSTRACT
I n this chapter we are going to be traveling almost all the way from one end of the graphics pipeline to the other – from world space to just behind screen space – to understand some of the low-level processes
which take place at the time primitives are transformed to pixels in the raster. In particular, the goal for this chapter is to learn algorithms to clip and rasterize lines and polygons. These are operations a user cannot herself call directly or interact with via a high-level API such as OpenGL, which is not a bad thing as she can devote herself then to modeling and animation. Nevertheless, it’s useful to have a grasp overall of the functioning of the pipeline. We’ll not attempt here a comprehensive coverage of raster algorithms, but focus instead on four which are commonly implemented and fairly representative.
