The walkers spawns randomly in the canvas , the canvas has a texture input which is invisible, so the walker lands somewhere in that textured canvas and then it check the pixel brightness of the canvas texture from its position and it chooses a direction to follow.

For now Ive created only 4 walkers, but more could be added.

I am going to try to evolve this more.

The webcam can be used as texture input, but you have to sit still for a while =) !