Yeah, pretty much, though really the colors are based on how long it takes a point to "escape" the set, if it does, with the blackness being ones that never do (to whatever level of diligence you have time to compute "never"). I was thinking the center black bug would be a deep crevasse or the "floor", with mountains rising on either side, so you could wander around in the canyons around a giant flat lowland, surrounded by mountain ridges.