A region is a set of methods for scanline clipping and drawing and the related data format invented by Bill Atkinson in the early 1980's. Regions are an evolution of Scanline Clipping that is much more effecient than traditional Scanline Clipping.

By having multiple scanlines that are identically represented only once it is possible to often keep the representation of a scanline group in a set of CPU registers, thus limiting memory accesses, and allowing for both vertical and horizontal runs in drawing operations that are clipped by a region. This is the primary factor that makes regions more effecient than traditional scanline clipping.

WIP : Work In Progress : WIP

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