GPU-based rendering of sparse low-degree implicit surfaces

Implicit surface is a well-known surface representation. Geometric details of an object can be represented using less surface primitives than other representations such as polygonal meshes. In this paper, we propose a fast and a direct rendering method of SLIM (Sparse Low-degree IMplicit) surfaces using recent programmable GPUs. Our approach establishes a direct rendering of implicit surfaces based on the ray casting approach. Geometric processes such as an intersection between a ray and an implicit surface and blending for PU (Partition of Unity) are performed in the fragment program on GPUs. For large models, a hierarchical structure of a SLIM surface can be used for LOD rendering or view frustum culling to speed up the rendering. We demonstrate that highly parallel processing using GPUs enables efficient rendering of implicit surfaces.