Last week, I wrote an article about using Flash 8 Perlin noise to generate a wood texture. Today, it's marble.

According to this link, the Perlin formula for marble is:

Again, we don't want to do math on every pixel -- too slow. So, how do we do this with the existing Flash 8 API? First, let's pretend that the perlin term in the above equation is not there. Here's what our image would look like (this image is arbitrarily blue monochrome):

The Flash 8 documentation for perlinNoise() has this intriguing statement:

You can use Perlin noise functions to simulate natural phenomena and landscapes, such as wood grain, clouds, and mountain ranges.

OK. That sounds like fun. But how is this done? It's not immediately obvious, at least not to me. So I googled .

According to these links (here and here), the formula for wood is: