Making 3D textures practical

While 2D texture mapping is one of the most powerful rendering techniques that make 3D objects appear visually interesting, it suffers from visual artifacts produced when 2D image patterns are wrapped onto the surface of objects with arbitrary shapes. On the other hand, 3D texture mapping generates highly natural visual effects in which objects appear carved from lumps of materials rather than laminated with thin sheets as in 2D texture mapping. Storing 3D texture images in a table for fast mapping computations, instead of evaluating procedures on the fly, however, has been considered impractical due to the extremely high memory requirements. In this paper, we present a new effective method for 3D texture mapping designed for real-time rendering of polygonal models. Our scheme attempts to resolve the potential texture memory problem arising from the very large size of 3D images by compressing them using a wavelet-based encoding method. The experimental results on various non-trivial 3D textures and polygonal models show that high compression rates are achieved with few visual artifacts in the rendered image and a small impact on rendering time. The simplicity of our compression-based scheme will make it possible to implement practical 3D texture mapping in software/hardware rendering systems including the real-time 3D graphics APIs like OpenGL and Direct3D.