Displacement and Normal Map Creation For Pairs of Arbitrary Polygonal Models Using GPU and Subsequent Model Restoration
Ilya Tisevich, A. V. Ignatenko · 2007
Displacement maps were originally intended for mostly superficial alterations of polygonal models, while being artificially obtained by means of various raster graphics software. Now, though, with rapid development of graphics hardware and its constantly increasing level of programmability it becomes possible to apply or simulate displacement mapping in real time, which renders it a very promising technique for making polygonal scene visualisations look even more realistic. It is also possible to utilize the displacement approach for lossy (or even lossless, considering significant data overhead) 3d-models compression algorithms. If combined with dedicated model compression methods and image and binary data compression algorithms, displacement mapping can result in dramatically improved overall compression ratios. In this article a complete life cycle of differential displacement maps is described, including proposed algorithm of GPU-based map creation and an algorithm of model restoration. It is shown that the described algorithm is capable of all of the features of conventional raytracing-based algorithms, while significantly outperforming them in terms of speed and feedback times, which renders it much more suitable for real life development process. Also, a multi-level displacing approach is presented, clearing the possibilities of non-height-field model details representation.