1. A graphics processing apparatus, comprising: a clipping unit; a read-only memory connected to the clipping unit, the read-only memory configured to store a clipping program; a read-write memory connected to the clipping unit, the read-write memory configured to store a patch program; and an addressing unit connected to the read-only memory and the read-write memory, the addressing unit configured to selectively address one of the read-only memory and the read-write memory based on a set of input conditions, wherein the set of input conditions are related to at least one of a set of characteristics of a graphics primitive to be clipped and a set of characteristics of a set of clipping planes associated with the graphics primitive to be clipped.