Weilin Hou wrote:
> 
> I used two perfect sine waves at 90 degrees to each other to make a fake
> wavy water surface and it showed square caustics on the bottom, when photon
> mapping used. Since in real life, lights will be focused and defocused in
> the water body with depth, I put in a slope in the water (isosurface,
> pretty much from surface to bottom) to see if indeed it'll converge and
> diverge. It seems showing only divergence (focused region/line get wider
> and wider with depth). I varied the water depth and wavelength of waves
> enough to make me believe that POV is not doing what I hope it was doing. I
> had thought when photon mapping was used, it stores actual refraction point
> locations for later ray tracing so it'll be very accurate when enough
> photons used. Why am I wrong here? Are there any corners being cut to
> "fake" these caustics?

There are examples in the POV-Ray sample scenes showing how you can use 
photon mapping for generating caustics including glass focussing light. 
  You also have to understand the way photon mapping works and realize, 
that the appearance of caustics is much influenced by the photon 
settings used and not only by the scene geometry and textures.

If you still think there is something wrong in the way POV-Ray does 
photon mapping you should post a minimal but complete test scene and 
explain what you think should be different in the result.

Christoph

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Last updated 03 May. 2005 _____./\/^>_*_<^\/\.______

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