Method of displaying optical effects within water using accumulation buffer

A precise shading model is required to display realistic images. Recently research on global illumination has been widespread. In global illumination, problems of diffuse reflection have been solved fairly well, but some optical problems after specular reflection and refraction still remain. Some natural phenomena stand out in reflected/refracted light from the wave surface of water. Refracted light from water surface converges and diverges, and creates shafts of light due to scattered light from particles. The color of the water is influenced by scattering/absorption effects of water molecules and suspensions. For these effects, the intensity and direction of incident light to particles plays an important role, and it is difficult to calculate them in conventional ray-tracing because light refracts when passing through waves. Therefore, the pre-processing tracing from light sources is necessary. The method proposed here can effectively calculate optical effects, shaft of light, caustics, and color of the water without such pre-processing by using a scanline Z-buffer and accumulation buffer.

[1]  Pat Hanrahan,et al.  Illumination from curved reflectors , 1992, SIGGRAPH.

[2]  Brian A. Barsky,et al.  Modeling and rendering waves: wave-tracing using beta-splines and reflective and refractive texture mapping. , 1987, TOGS.

[3]  James T. Kajiya,et al.  Ray tracing volume densities , 1984, SIGGRAPH.

[4]  Nelson Max,et al.  Light diffusion through clouds and haze , 1986, Comput. Vis. Graph. Image Process..

[5]  Tomoyuki Nishita,et al.  A Method for Displaying Metaballs by using Bézier Clipping , 1994, Comput. Graph. Forum.

[6]  Mark Watt,et al.  Light-water interaction using backward beam tracing , 1990, SIGGRAPH.

[7]  Alain Fournier,et al.  A simple model of ocean waves , 1986, SIGGRAPH.

[8]  R. Victor Klassen,et al.  Modeling the effect of the atmosphere on light , 1987, TOGS.

[9]  Paul S. Heckbert Adaptive radiosity textures for bidirectional ray tracing , 1990, SIGGRAPH.

[10]  Mikio Shinya,et al.  Rendering techniques for transparent objects , 1989 .

[11]  Pat Hanrahan,et al.  Beam tracing polygonal objects , 1984, SIGGRAPH.

[12]  Tomoyuki Nishita,et al.  Ray tracing trimmed rational surface patches , 1990, SIGGRAPH.

[13]  Tomoyuki Nishita,et al.  A shading model for atmospheric scattering considering luminous intensity distribution of light sources , 1987, SIGGRAPH.

[14]  Tomoyuki Nishita,et al.  Continuous tone representation of three-dimensional objects illuminated by sky light , 1986, SIGGRAPH.

[15]  James F. Blinn,et al.  Light reflection functions for simulation of clouds and dusty surfaces , 1982, SIGGRAPH.

[16]  Tomoyuki Nishita,et al.  Display of the earth taking into account atmospheric scattering , 1993, SIGGRAPH.

[17]  James F. Blinn,et al.  A generalization of algebraic surface drawing , 1982, SIGGRAPH.

[18]  Holly E. Rushmeier,et al.  A progressive multi-pass method for global illumination , 1991, SIGGRAPH.