Nailboards: A Rendering Primitive for Image Caching in Dynamic Scenes

. This paper proposes a simple augmentation to texture mapping hardware which produces the correct depth buffer content and hence correct visibility when replacing complex objects by partially transparent textured polygons. Rendering such polygons exploits frame-to-frame coherence in image sequences of dynamic scenes. Correct depth values are obtained by keeping a small depth delta for every texel which represents the texel's deviation from the textured polygon. The polygon's depth values are modified at every pixel to match the depicted object's geometry. 1 Introduction and Motivation Rendering acceleration in three-dimensional computer graphics is usually achieved with dedicated graphics hardware. Available accelerators generate up to sixty frames per second of moderately complex scenes. Their major limitation is that every frame is rendered from scratch even though smooth frame sequences contain a great amount of coherence. Nevertheless depth-buffered scan conversion of polygons e..