On Wed, Jul 30, 2008 at 8:00 PM, Casey Duncan
<casey@xxxxxxxxxxx> wrote:
On Jul 30, 2008, at 11:08 AM, Knapp wrote:
[..]
One of the links I posted talked about the 3d+ Speed problems and how to fix them. Have you see that yet?
I had seen that before. The gradient optimization mentioned is really only applicable to classic Perlin noise. The Perlin Improved noise algorithm optimizes the gradients in a different way. The gradients themselves in "improved noise" are no longer random, though they are selected in a pseudo-random fashion, by hashing the incoming coordinates. Basically. the moral equivalent of the optimization is already present in "improved" noise.
The scaling problem for higher dimensions is solved nicely by simplex noise, which grows linearly in cost as you add dimensions, rather than geometrically. However, simplex noise looks considerably different, and so even a higher cost 4D Perlin noise function is probably still desirable for applications not sensitive to that cost. 4D noise is highly useful for real-time applications where you desire to animate a 3D texture, and there, cost is typically important.
-Casey
You can always take the easy way out. Four years from now your computer will be so fast you will not care so much about this. :-)
Also when doing real-time 3d with movement, I use Blender, and they let you map video to the surface. Thus you can precalculate the image and just play it back. I guess there are some times when this is not good enough, like when you want interaction.
--
Douglas E Knapp
http://sf-journey-creations.wikispot.org/Front_Page