Interactive shading for surface and volume visualization on graphics workstations

Shading is an effective exploratory visualization tool widely used in scientific visualization. Interactive, or close to interactive, shading of images offers significant benefit, but is generally too computationally expensive for graphics workstations. A novel method for providing interactive diffuse and specular shading capability on low-cost graphics workstations is described. Application to digital elevation models, iso-surfaces in volumetric images, and color-coded aspect maps are illustrated and an analysis of artifacts, and of ways of minimizing artifacts, is given