SURFELS - Surface Elements as Rendering Primitives
This project is motivated by the desire to render complex three dimensional objects as efficiently as possible. The fundamental approach of this research is to use surfels (or surface elements) as an alternative display primitive. Objects are represented as a dense set of surface point samples. Surfel attributes comprise depth, texture color, normal, and others. As a pre-process, an octree-based surfel representation of a geometric object is computed. During rendering, a hierarchical forward warping algorithm projects surfels to the screen. Surfel objects offer complex shape, low rendering cost and high image quality, which makes them specifically suited for low-cost, real-time graphics, such as games.
Background & Objective: The core objective of this project is to combine volume, image, and geometry rendering in one unified rendering pipeline. We have developed several new algorithms for surfel generation and rendering and we implemented a prototype surfel rendering system. We have applied for 4 patents in 1999 and are currently applying for 4 additional patents. We are currently exploring hardware implementations of the surfel pipeline.
Technical Discussion: We propose a new method of rendering objects with rich shapes and textures at interactive frame rates. Our rendering architecture is based on simple surface elements (surfels) as rendering primitives. Surfels are point samples of a graphics model. In a preprocessing step, we sample the surfaces of complex geometric models along three orthographic views. At the same time, we perform computation-intensive calculations such as texture, bump, or displacement mapping. By moving rasterization and texturing from the core rendering pipeline to the preprocessing step, we dramatically reduce the rendering cost. From a modeling point of view, the surfel representation provides a mere discretization of the geometry and hence reduces the object representation to the essentials needed for rendering. In a sense, a surfel relates to what we call the ``lingua franca'' of rendering. Surfels will allow us to combine image-based rendering, adaptive curved-surface tessellation, constructive solid geometry, unstructured volume data, particle systems, and so on in one common rendering framework.
Contact: Joseph Katz
Technology Area: Graphics
Modification Date: September 14, 2007
