Rapid Exploration of Curvilinear Grids Using Direct Volume Rendering

Abstract

Fast techniques for direct volume rendering over curvilin-ear grids (common to computational \nuid dynamics and -nite element analysis) are developed. Three new projection methods that use polygon-rendering hardware for speed are presented and compared with each other and with pre-vious methods for tetrahedral grids and rectilinear grids. A simplied algorithm for visibility ordering, based on a combination of breadth-rst and depth-rst searches, is described. A new multi-pass blending method is described that reduces visual artifacts that are introduced by linear interpolation in hardware where exponential interpolation is needed. Visualization tools that permit rapid data band-ing and cycling through transfer functions, as well as region restriction, are described. 1