Exploiting coherence in hierarchical visibility algorithms

Abstract

AbstractWe present a series of simple improvements that make use of temporal and spatial coherence in the scope of hierarchical visibility algorithms. Thehierarchy updatingavoids visibility tests of certain interior nodes of the hierarchy. Thevisibility propagationalgorithm reuses information about visibility of neighbouring spatial regions. Finally, theconservative hierarchy updatingavoids visibility tests of the hierarchy nodes that are expected to remain visible. We evaluate the presented methods in the context of hierarchical visibility culling usingocclusion trees. Copyright © 2002 John Wiley & Sons, Ltd.