IMPROVING GLOBAL ILLUMINATION WITH A-BUFFER TECHNIQUE

Two of the main issues m radiosity generated images are efficient form factor computation and proper mesh generation. Although hemicube algorithm remains a simple and fast method for radiosity form factor computation, its simple sampling scheme for the hemicube pixels causes unacceptable accuracy in its result. We improve the accuracy by applying the A-buffer anti-aliasing technique to handle the hemicube visibility and aliasing, thereby alleviating this inaccuracy that was originally caused by the under/over estimation of the projections on the hemicube pixels. An appropriate meshing scheme, based on the inherent data structure of the A-buffer algorithm, provides better shading and eliminates light leaks around shadow boundaries. The final radiosity solution incorporating these two features is implemented with the progressive refinement approach to improve interactivity.

Author dc:creator

• LIM CHOO HONG