Granular visibility queries on the GPU

Efficient visibility queries are key in many interactive rendering techniques, such as occlusion culling, level of detail determination, and perceptual rendering. The occlusion query mechanism natively supported by GPUs is carried out for batches of rendered geometry. In this paper, we present two novel ways of determining visibility by intelligently querying summed area tables and computing a variant of item buffers. This enables visibility queries of finer granularity, e.g., for sub-regions of objects and for instances created within a single draw call. Our method determines the visibility of a large number of objects simultaneously which can be used in geometry shaders to cull triangles, or to control the level of detail in geometry and pixel shaders under certain rendering scenarios. We demonstrate the benefits of our method with two different real-time rendering techniques. CR Categories: I.3.7 [Three-Dimensional Graphics and Realism]: Visible line/surface algorithms;

• Type: Conference
• Year: 2009
• Where: SI3D
• Authors: Thomas Engelhardt, Carsten Dachsbacher
• Keywords: Computer Graphics, Efficient Visibility Queries, Rendering Techniques, SI3D 2009, Visibility Queries