Fast volume render techniques for interactive analysis

Without graphics hardware, interactive volume rendering is almost impossible with the current generation of computers and software. We describe the implementation of a volume renderer for interactive analysis of confocal images. We propose several techniques to accelerate the rendering of grey-value volumes. We propose to illuminate the volume selectively with ray templates to get a proper shadow cue in the shortest feasible time. In the viewing phase, rendering is distinctively accelerated for four user interactions: (1) a total change by successive adaptive refinement, (2) an unknown change in the view with this refinement strategy combined with suspended interpolation, (3) a known change in the view by recalculating only that part and (4) a view translation by recalculating the uncovered part.