Noise algorithms are a fantastic thing to have in your 3D graphics bag of tricks. I can’t tell you how many times Perlin noise has saved my life. Unfortunately, most good noise algorithms don’t lend themselves particularly well to computation on the GPU. Enter Cell noise.
Cell noise, otherwise known as Worley noise, is actually a visualization of a Voronoi diagram: given a random scattering of points, color each pixel on the surface relative to the distance from the closest randomly scattered point. Cell noise appears all over nature, it looks great, and is easy to compute! A cell noise function can give us a volume of noise, which we can sample in a fragment shader, giving us seamless patterns on any object – no UV mapping required. Cool!