Real-Time Rendering   Chair: John Hart , Washington State University   Real-Time Shadows, Reflections, and Transparency using a Z-Buffer/Ray Tracer Hybrid   Merging ray tracing with real-time hidden-surface algorithms such as the z-buffer algorithm offers a smooth transition from interactive display with approximate soft shadows, reflections, and transparency to full ray tracing with all of its associated effects. This is done by using the ray tracer only for tracing shading rays at the vertices of polygons and using another hidden-surface technique for hidden-surface removal in conjunction with Gouraud interpolation.   Abe Megahed Hypercosm, Inc. 1212 Fourier Drive Madison, Wisconsin 53717 USA abem@hypercosm3d.com   Phong Shading at Gouraud Speed   With a few matrix rotations during polygon setup, Phong's per-pixel renormalization and exponentiation are reduced to linear interpolation and fast multiply for use with real-time software or low-end hardware.   Greg Rivera Virtus Corporation Director of Applications 114 MacKenan Drive, Suite 100 Cary, North Carolina 27511 USA greg.rivera@virtus.com   Quasi-Linear Z-Buffer   A new type of depth buffer with quasi-linear mapping from the eye to screen space. It significantly improves depth resolution and is easy to use with standard 3D hardware and APIs.   Eugene Lapidous Trident Microsystems Inc. 189 North Bernardo Avenue Mountain View, California 94043 USA lapidous@acm.org   Occlusion Culling with Optimized Hierarchical Z-Buffering   Z-buffer hardware can be greatly accelerated by adding a conservative culling stage that employs an optimized variation of hierarchical z-buffering to cull occluded geometry.   Ned Greene Ned Greene Consulting 140 Russell Avenue Portola Valley, California 94028 USA ned@ngreene.com