Patent US 5,086,496

A method for displaying three dimensional images starts by initially forming a "stripped" partition of a view window by passing a contractible, vertical attachment through each scene vertex in the view window. Faces from the scene are chosen and added to a planar partition by selecting a vertex of the chosen face; locating its corresponding vertical attachment and traveling along the line segment which is initiated at that vertex. As the line segment traverses each region and makes region to region transitions, the partitions are updated. Concurrently, each new region in the partition has a visibility pointer assigned to it. When an entire scene face has been added, a set of visibility pointers associated with regions interior to the added scene face enable depth comparisons to be carried out.