Conservative visibility preprocessing using extended projections

Visualization of very complex scenes can be significantly accelerated using occlusion culling. In this paper we present a visibility preprocessing method which efficiently computes potentially visible geometry for volumetric viewing cells. We introduce novel extended projection operators, which permits efficient and conservative occlusion culling with respect to all viewpoints within a cell, and takes into account the combined occlusion effect of multiple occluders. We use extended projection of occluders onto a set of projection planes to create extended occlusion maps; we show how to efficiently test occludees against these occlusion maps to determine occlusion with respect to the entire cell. We also present an improved projection operator for certain specific but important configurations. An important advantage of our approach is that we can re-project extended projections onto a series of projection planes (via an occlusion sweep), and accumulate occlusion information from ...

• Type: Conference
• Year: 2000
• Where: SIGGRAPH
• Authors: Frédo Durand, George Drettakis, Joëlle Thollot, Claude Puech
• Keywords: Computer Graphics, Extended Projection, Occlusion Culling, Occlusion Maps, SIGGRAPH 2000