Simulating worlds on the GPU: Four billion years in four minutes

The simulation randomly generates seed locations for plates, with an initial velocity. These plates grow in size over time with a simple aggregation model, which randomly selects neighbouring points and adds them to a plate if they have not already been assigned to another plate. All of the pixels within a plate store the velocity of the plate's movement. Continuous movement of the plates is difficult, as it would require plate boundaries to account for movements measured in fractions of a pixel. To avoid this, the plates are instead moved at discrete time-steps, by a whole pixel either horizontally or vertically. These times are randomised for each plate such that the average velocity is maintained at the set speed and direction, and also so that it is unlikely that neighbouring plates will move simultaneously. Plate collisions occur when some boundary pixels of one plate move onto a location previously occupied by pixels belonging to another plate.