Warp wrote:

>   POV-Ray is a prime example of a raytracer which has bounding box
> hierarchy optimizations: Render a simple scene with 10 spheres in a
> home-made raytracer and with POV-Ray, and the render times may be
> comparable. Render a scene with 100000 spheres with the home-made
> raytracer and POV-Ray and the Sun will probably die before the former
> gets the job done, while POV-Ray doesn't take significantly longer.

Very true. Now I have to check every single object with every single
ray. That is O(N) and that is way too much. I have to study BSP trees at
some point. And whatever other similar methods there are.

>   Btw, for a very good-quality and very fast RNG, you could also try
> this: http://burtleburtle.net/bob/rand/isaacafa.html
> 
>   It's horribly ugly C code. I have made a clean C++ implementation if
> you are interested.

Actually I'm interested. I remember reading about Isaac a few years ago
but missed it now. Do you know how it compares to Mersenne Twister
speed-wise? I don't need 100% cryptographic robustness but fast
generation and decent randomness for (say) 1280x1024x10x10000 numbers.
(resolution * rays/pixel * passes). So the cycle must be a lot larger
than that :)

Most likely I'll implement my own class but if you care to show me
yours, that would be appreciated!

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