Optimization of screen-space directional occlusion algorithms

Developers of video games and simulations from the day one have been trying to improve visuals of their products. The appearance of the scenes depends to a large extent on the approximation to the physical basis of light behaviour in the environments presented. The best effects in this regard are global illumination. However, it is too computationally expensive. One of the methods to simulate global illumination without a lot of processing is Screen-Space Ambient Occlusion. Many implementations of this technique were created, though few take into account direction and colour of the incoming light. An exception is a technique named SSDO – Screen-Space Directional Occlusion. Unfortunately, it suffers from the same drawbacks as its less realistic cousins, such as noise and banding while also remaining moderately expensive for computation. The main purpose of this paper is to optimize basic SSDO method using technique called Statistical Volumetric Obscurance, enhancing its performance while retaining plausible visual effect.