# Worley noise

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Worley noise is a noise function introduced by Steven Worley in 1996. In computer graphics it is used to create procedural textures, [1] i.e. textures that are created automatically with arbitrary precision and do not have to be drawn by hand. Worley noise comes close to simulating textures of stone, water, or biological cells.

## Basic algorithm

The algorithm chooses random points in space (2- or 3-dimensional) and then for every location in space takes the distances dn to the nth-closest point (e.g. the second-closest point) and uses combinations of those to control color information (note that dn+1 > dn). More precisely:

• Randomly distribute feature points in space organised as grid cells. In practice this is done on the fly without storage (as a procedural noise). The original method considered a variable number of seed points per cell so as to mimic a Poisson distribution, but many implementations just put one.
• At run time, extract the distances dn from the given location to the nth-closest seed point. This can be done efficiently by visiting the current cell and its neighbors.
• Noise W(x) is formally the vector of distances, plus possibly the corresponding seed ids, user-combined so as to produce a color.

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## References

1. Patrick Cozzi; Christophe Riccio (2012). OpenGL Insights. CRC Press. pp. 113–115. ISBN   978-1-4398-9376-0.