Abstract

In a computer graphics system, an address generator processes physical and virtual addresses using a common command set. The address generator formulates addresses as a function of distance from the origin of the desired destination area in a destination memory to the requested position in the destination area. A plurality of context drawing commands is used to define a desired context in which drawing graphics commands operate. Different parts of the context are changeable/redefinable independently of the other parts. Graphics commands have a format of multiple fields having corresponding parameters arranged in order of common use of the parameter such that fields of less commonly used parameters are at an omittable end of the format. Raster drawing commands are delimited by a beginning and end indicator to form a drawing unit. For clip list processing, a drawing unit is stored as a single occurrence in the system command buffer.