[tripzilch]

Looks cool. The article could use a bit more explanation of what exactly I'm looking at.

Is this is a flood-fill algorithm?

Cause what I remember from back in the day when you could still watch MS Paint do the flood fill, a more efficient version fills out horizontal spans all at once, instead of growing like an ink blot.

But it looks cool.

EDIT: maybe this is one of those "use the entire RGB colour space" type of renderings? (see http://allrgb.com )

[morsch]

It's mostly a visualisation of the tree underlying the colours, I'd say. The pixels of the canvas form a grid, and a spanning tree is created for this graph. A spanning tree contains all nodes of a graph, but only a subset of the edges. A tree is a graph that does not contain any cycles.

[thomasahle]

It's a colored version of this: https://en.wikipedia.org/wiki/Uniform_spanning_tree