Beyond Triangles : GigaVoxels Effects In Video Games

Voxel representations are commonly used for scientific data visualization, but also for many special effects involving complex or fuzzy data (e.g., clouds, smoke, foam). Since voxel rendering permits better and easier filtering than triangle-based representations it is also an efficient high-quality choice for complex meshes (with several triangles per pixel) and detailed geometric data (e.g., boats in Pirates of the Caribbean). We have shown in [Crassin et al. 2009] that highly detailed voxel data can be rendered in high quality at real-time rates. The work foreshadows the use of very large volumetric data sets in the context of video-games. Our system, based on ray-casting of a generalized sparse octree structure on GPU, achieves high rendering performance for billions of voxels. To further underline the usefulness in the context of video games, this sketch introduces new features of our system, namely free object instantiation and the mixing with existing triangle scenes. We also demonstrate how to render complex visual effects like depth-of-fields or approximated soft shadows in very efficient ways, exploiting intrinsic properties of our multi-resolution scheme