Starting with a entirely black image, a few base pixels are selected close to the corners of an imaginary equilateral triangle, whose centre corresponds to the centre of the image.
The base pixels are coloured red, green or blue based on their corner.
The intensities of the colour components of all other pixels is affected by the base pixels in a sort of gravitational way.
Once all pixels are ranked by the inherited intensities of their components, they can be recursively picked and assigned unique colours.
Image Licence: Public Domain (CC0).
