Worley noise

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Example picture generated with Worley noise's basic algorithm. Worley.jpg
Example picture generated with Worley noise's basic algorithm.
When computing Worley noise, each seed is located within its own grid square. (Grid is not a part of the noise) Worley-f1 With Grid.jpg
When computing Worley noise, each seed is located within its own grid square. (Grid is not a part of the noise)
Worley noise can be differentiated once to generate a normal map. (Grid is not a part of noise) Worley Noise F1 Normal.png
Worley noise can be differentiated once to generate a normal map. (Grid is not a part of noise)

Worley noise, also called Voronoi noise and cellular noise, is a noise function introduced by Steven Worley in 1996. Worley noise is an extension of the Voronoi diagram that outputs a real value at a given coordinate that corresponds to the Distance of the nth nearest seed (usually n=1) and the seeds are distributed evenly through the region. Worley noise is used to create procedural textures. [1] [2]

Contents

Worley noise of Euclidean distance is differentiable and continuous everywhere except on the edges of the Voronoi diagram of the set of seeds and on the location of the seeds.

Basic algorithm

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

See also

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References

  1. Patrick Cozzi; Christophe Riccio (2012). OpenGL Insights. CRC Press. pp. 113–115. ISBN   978-1-4398-9376-0.
  2. 1 2 Worley, Steven (August 1996). "A cellular texture basis function". Proceedings of the 23rd annual conference on Computer graphics and interactive techniques. pp. 291–294. doi:10.1145/237170.237267. ISBN   0897917464. S2CID   2759214 via ACM Digital Library.

Further reading