**Worley noise** (also called Voronoi noise) is a [[article:noise|noise]] function first proposed by Steven Worley in 1996. Worley noise is an extension of the [[article:voronoi_diagram|Voronoi diagram]] that, for each coordinate, returns a real value corresponding to the distance of the $n$th nearest site.
==== Creating Worley noise (Processing) ====
Processing is a Java-based IDE that requires minimal setup to get images onto the screen. Processing is free to download at [[https://processing.org|processing.org]].
=== Setup ===
void setup(){
size(500,500);
background(100);
}
void draw(){
loadPixels();
updatePixels();
}
The ''setup()'' function is called once. In it, the canvas size is set to 500 by 500 pixels on the $x$ and $y$ axes, respectively. The ''background()'' function sets the background colour of the canvas. In this case, the background colour has been set to $(100,100,100)$, just grey.
The ''draw()'' function has been created for later. It is called repeatedly, and for now, it ''loadPixels()'' to get data from the canvas into the ''pixels[]'' array, and it ''updatePixels()'' to update the canvas with data from the ''pixels[]'' array. The result of this code should be a static grey canvas.
\\
\\
=== Creating a grid (optional) ===
A naive approach to Worley noise would be to iterate over each site for each canvas pixel. Each canvas pixel must be processed; that is inevitable. However, we can use optimizations to minimize the number of sites we must process per-pixel.
The optimization involves a grid-based approach where each grid cell has a fixed number of sites. In the code below, a 6x6 grid is used to plot 36 sites (1 site/cell).
PVector[] sites;
void setup(){
size(500,500);
background(100);
sites = new PVector[36];
// plot loops here
}
\\
\\
=== Plotting points ===
\\
\\
=== Calculating distance ===
\\
\\
==== See also ====
* [[article:computer_graphics|Computer graphics]]
* [[article:noise|Noise]]