Break Terrain generation down into phases

[StLoch]

Terrain generation should be broken up into phases (using the builder pattern?) and made to operate on a single interface, rather than manipulating raw data that eventually gets built into a more complex object.

[datalurkur]

Since I imagine terrain storing its data in a 3-dimensional array, this would be a logical progression: 1) Add world layer (this will basically generate a single heightmap, give it a type, and then push it on top of any existing layers) 2) Erode world - this will perform some kind of natural erosion operation, be it thermal or hydrological (note that this doesn't actually add water to the world) 3) Grow features - this is a special step used to add pockets of trace minerals underground in the pre-existing world, or create underground caves (basically the same as the previous example, but creating empty space instead of a mineral type) 4) Simulate seismic activity (This will take chunks of the world and "shear" them to create fault lines, also determining proper places for lava pipes and lakes)

[datalurkur]

World layering is more or less working. I'll move on to erosion and seismic simulation (minus lava flows), next.

[datalurkur]

Terrain gen now has seismic "shearing" and some basic nearest-neighbor-averaging-style erosion. I toyed a bit with the averaging window, and settled on a weighted system. Examine TerrainBuilder for more details.

[datalurkur]

This is pretty much broken up. I'd say we need to create sub-tickets for specific terrain-gen phases.