About volumetric caustics.

Practical and theoretical implementation discussion.
ingenious
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Re: About volumetric caustics.

Post by ingenious » Sun Nov 17, 2013 12:29 am

On this scene neither VCM nor Metropolis will help. I suggest caching illumination in some data structure and then do distribution ray tracing at the first bounce from the camera to query this structure. That is, using something like VRay's light cache. Irradiance caching is also great for this scene, but people in high quality rendering seem to move away from algorithms that interpolate directly visible illumination.
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shiqiu1105
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Joined: Sun May 27, 2012 4:42 pm

Re: About volumetric caustics.

Post by shiqiu1105 » Sun Nov 17, 2013 1:05 am

ingenious wrote:On this scene neither VCM nor Metropolis will help. I suggest caching illumination in some data structure and then do distribution ray tracing at the first bounce from the camera to query this structure. That is, using something like VRay's light cache. Irradiance caching is also great for this scene, but people in high quality rendering seem to move away from algorithms that interpolate directly visible illumination.
What about photon mapping. I knew that it can produce noiseless images fast. But it's not recommended?

shiqiu1105
Posts: 138
Joined: Sun May 27, 2012 4:42 pm

Re: About volumetric caustics.

Post by shiqiu1105 » Sun Nov 17, 2013 4:07 am

ingenious wrote:On this scene neither VCM nor Metropolis will help. I suggest caching illumination in some data structure and then do distribution ray tracing at the first bounce from the camera to query this structure. That is, using something like VRay's light cache. Irradiance caching is also great for this scene, but people in high quality rendering seem to move away from algorithms that interpolate directly visible illumination.
Also, I was trying to google light caching algorithm, but got little useful result of how it's implemented. Any pointers? Thanks~

friedlinguini
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Joined: Thu Apr 11, 2013 5:15 pm

Re: About volumetric caustics.

Post by friedlinguini » Sun Nov 17, 2013 3:56 pm

shiqiu1105 wrote:What about photon mapping. I knew that it can produce noiseless images fast. But it's not recommended?
Not recommended by who, and for what? There are some things that photon maps are good for (avoiding noise, rendering LSDSE light paths, ease of implementation), and some things that they are less well suited for (rendering landscapes, slower convergence than BDPT, glossy materials, might require some manual parameter tweaking).

As far as I know we don't yet have a One True Algorithm (low bias/error, noiseless, accurate previews, parameterless, handles arbitrary materials and geometry, easy to implement, etc.). You have to decide what features are important, and what weaknesses you can live with.

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