A First Step towards Occlusion Culling in OpenSG PLUS

The fast increasing size of datasets in scientific computing, mechanical engineering, or virtual medicine is quickly exceeding the graphics capabilities of modern computers. Toolkits for the large model visualization address this problem by combining efficient geometric techniques, such as occlusion and visibility culling, mesh reduction, and efficient rendering. OpenSG PLUS is such a toolkit with support for large models. In this paper, we present three techniques for occlusion culling in OpenSG PLUS. The first technique uses the z-buffer to determine the visibility of a bounding box. The second technique uses the stencil-buffer to get visibility information and the third technique exploits the HP Occlusion Culling Flag. All three techniques are conservative and work on arbitrary scenes without any geometric or topological assumptions. CR Categories: I.3.3 [Picture/Image Generation]: Viewing Algorithms, Occlusion Culling; I.3.4 [Graphics Utilities]: Application Packages, Graphics Packages; I.3.7 [Three-Dimensional Graphics and Realism]: Hidden Line/Surface Removal;