Evaluating pixel shaders consumes a growing share of the computational budget for real-time applications. How- ever, the significant temporal coherence in visible surface regions, lighting conditions, and camera location al- lows reusing computationally-intensive shading calculations between frames to achieve significant performance improvements at little degradation in visual quality. This paper investigates a caching scheme based on reverse reprojection which allows pixel shaders to store and reuse calculations performed at visible surface points. We provide guidelines to help programmers select appropriate values to cache and present several policies for keeping cached entries up-to-date. Our results confirm this approach offers substantial performance gains for many com- mon real-time effects, including precomputed global lighting effects, stereoscopic rendering, motion blur, depth of field, and shadow mapping.

@inproceedings{Nehab:2007:ARS,
   author = "Diego Nehab and Pedro V. Sander and Jason Lawrence and Natalya
      Tatarchuk and John R. Isidoro",
   title = "Accelerating Real-Time Shading with Reverse Reprojection Caching",
   booktitle = "Graphics Hardware",
   year = "2007",
   month = aug
}