Sunflow Rendering System

[viewon01]

Hi,

I'm currently learning the SunFlow code to try to understand how it works... and I have find the "QMC" class.

But what it is ? Does someone can explain me ?

Thanks
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ViewOn01

http://www.codeplex.com/rs

[fpsunflower]

QMC stands for quasi-monte carlo.

The monte carlo method basicaly uses completely random numbers to estimate a function. A simple example might be figuring out the amount of soft-shadow at a point. You pick two random numbers to create a point on the surface of the light, then shoot the ray between your surface as this random position. Repeat this several times and average the number of rays that hit an object - this gives you soft shadows.

While the monte carlo method works quite well in theory, in practice we can do better. In graphics the functions we try to evaluate are fairly smooth so it pays off to distribute those random variables in a good way. "Quasi" monte carlo does this. Its a way to generate numbers that behave like random numbers, but that are better distributed.

If you want more details, you're going to have to dig into some maths. I would recommend the PBRT book. http://www.pbrt.org/

The paper that sunflow is based on can be found here: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.88.7937 (from Siggraph 2003 course notes).

[viewon01]

Thanks a lot for your explanation...

It is clear
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ViewOn01

http://www.codeplex.com/rs