From Wikipedia: The Buddhabrot is rendered by creating a 2-dimensional array of counters, one for each pixel. Then, a random (or, alternately, an evenly spaced) sampling of points c is iterated through the Mandelbrot function, and, for points which do escape within a chosen number of iterations, and are thus not in the Mandelbrot set, the counters for each pixel that the z value landed on are incremented (once per hit). After a large number of values c have been iterated, image colors (or color saturation/brightness) are then chosen based on the values recorded in the array.