Trouble is: What *is* a mountain? They're not like schematics placed at mapgen time. They're local maxima, certainly, but to which degree? Most of all: Mapgen usually works at 80x80 nodes at a time. That's not much room for a river. If it ought to extend into neighbouring mapchunks, then it has to be possible to calculate independently of terrain where the river will be. Creating the river after mapgen may be tempting, but in such a case the river won't be there when the player first passes by. And quite likely the player either won't ever show up again (for most of the terrain), will start building (and then the river cuts through his/her house?), or will never notice that a nice river came into existence at that spot.voxelproof wrote:Why not? Imo it'd me much more natural than creating closed up into more or less enclosed circular shapes ends of riverbeds. I do understand that for some reasons this could make shaping of terrain easier, but to achieve really good visual and realistic results the whole process should be done reverse: creating mountain first, then placing river source and then eroding a slope to create a true riverbed. This, of course, would be time-costly and a player would have to wait a little bit to see the final version of the landscape, but at least for the sake of the map generator art it's definitely worth trying out. Simple cellular automata mechanics would solve the issue.duane wrote: I don't know about terrainbrot, but valleys figures out where the rivers are going, then builds the terrain around them. I can't imagine trying to do it the other way around.
Obligatory screenshot, goblins taking over a fresh Adventuretest world: