Multi-projection On The Graphics Hardware For Rendering

Multi-perspective rendering has a variety of applications, examples include lens refraction, curved mirror reflection, caustics, as well depiction and visualization. However, multi-perspective rendering is not yet practical on polygonal graphics hardware, which so far has utilized mostly single-perspective (pin-hole or orthographic) projections.In this paper, we present two methodologies for real-time multi-perspective rendering on polygonal graphics hardware. Our approach is based on Geometry. It approximates a general multi-perspective projection surface (such as a curved mirror and lens) via a piecewise-linear triangle mesh, upon which each triangle is a simple multi-perspective camera, parameterized by three rays at triang le vertices. We derive analytic formula showing that each triangle projection can be implemented as a pair of vertex and fragment programs on programmable graphics hardware. The other approach is based on image. It uses cubic environment mapping with depth to represent the surrounding scene. Each ray on the multi-perspective surface is rendered by indexing into the environment mapping. We demonstrate real-time performance of a variety of applications enabled by our techniques, including reflection, refraction, caustics, and visualization.