A region of space is filled through exhaustive placement of slowly expanding boxes. Each box begins very small (2 x 2 pixels) and increases in size until an obstacle (surface border or other box) is encountered.
This probably isn’t the fastest way to fill a region, but it is certainly interesting to watch.
Color is introduced by assigning each box a specific color based on it’s y-origin. This coloring scheme resembles a cutaway exposing geologic sedimentary layers.
