Cellular (Voronoi) noise

Value noise gives soft, cloudy blobs. Cellular noise gives something completely different: a pattern of CELLS — cracked mud, reptile scales, stone, foam, a giraffe’s coat. It is built from the randomness you just learned, but used a new way: instead of a random value per cell, you scatter a random POINT in each cell, and color every pixel by its distance to the nearest point.

The recipe (this is the Worley / Voronoi algorithm): divide space into a grid; give each grid cell one random feature point. For a pixel, look at its own cell and the eight neighbours, measure the distance to each of those nine points, and keep the smallest. That nearest-point distance is the pattern — dark right at the points, brightening outward until you hit the border where two cells meet. Animate the points with u_time and the whole cellular field flows like something alive.

That is live cellular noise: the dark centres are the feature points (with a bright dot drawn on each), and the ridges are the cell borders. Change the 5.0 to scatter more or fewer cells, and watch the points drift with time.