Theoretical Results on the Priority Approach to Hidden·surface Removal

Many of Ule fundamental problems in computer graphics involve Ute notion of visibility. In one approach to Ute hidden-surface problem, priorities are assigned to Ute faces of a scene. A realistic image is Uten rendered by displaying the faces wiUt Ute resulting priority ordering. We introduce a tree-based formalism for describing priority orderings Utat simplifies an existing algoriUtm. As well, a decompositionbased algoriUtm is presented for classes of scenes Utat do not in general admit priority orderings. Finally, Ute tree-based formalism is used in the development of insertion and deletion algoriUtms Utat solve Ute problem of dynamically maintaining a priority ordering.