Fast Point Based Global Illumination

Point based rendering can simulate global illumination phenomenon fast and is widely used in movie production. This paper proposes a faster point based global illumination algorithm compared with the standard one. During our algorithm, the shading points generated by ray tracing are clustered in to groups. When doing point based rendering, the indirect illumination of each group´s center point is computed instead of each shading point. We use an error strategy to make the indirect illumination compute adaptively. This method is several times faster than the standard point based global illumination method, while preserves high rendering quality. What´s more, we implement our algorithm on GPU. In order to improve parallelism, we design a GPU-based cluster method and then implement the point based rendering process on GPU. The speed is times faster compared with the CPU one.