snow_land

Fills a height buffer with the mountain the ski run descends.

The shape is composed, not sampled. A massif of overlapping summit bells carries the mass, a general tilt drops the ground away toward the valley, ridged noise stands aretes up wherever the massif is high, and fine FBM roughens the whole surface. The piste is part of the same function: a corridor down the fall line takes the smooth field alone, level across its width and rolling gently along it, blended back into the mountain over a margin.

Dispatch it 2D over the grid, ceil(grid / 8) groups on each axis.

Buffers

binding	name	role
0	land	the height buffer written, row-major, grid * grid floats
1	ctrl	the parameters below

ctrl

slot	meaning
0	grid size
1	extent in metres, centred on the origin
2	seed
3	valley floor height
4	massif height
5	ridge amplitude
6	detail amplitude
7	tilt: the drop across the extent
8	piste half width
9	piste blend margin
10	piste roll amplitude
11	piste roll length
12	piste dish: the rise at the corridor edge