The valleys, cut into a landform at one sample.
Over every segment the sample's cell lists: the distance to the chord and where along it, the floor, channel half-width and depth interpolated there, and then the terms —
ground = landform − max cut + max fill − max notch
where a segment's cut is the landform's height above the floor over the
valley's cross-section, its fill the floor's height above the landform
over the same cross-section, and its notch the channel's depth over the
bed. One segment alone gives mix(landform, floor, shape) − depth · bed:
the bed at the floor less the channel's depth whichever way the landform
went, the floodplain at the floor, the walls blending out to the landform
at the reach. Every term is a maximum of continuous terms that are zero
for a segment out of reach, so the set of segments a sample sees can
change without the ground noticing.
The fill is the term the plan's min(landform, floor + profile) does not
have, and it is alluvium. The relief and the craters are not on the
lattice, so along a channel the landform dips under the floor wherever a
hollow of theirs falls on it, and a cut alone leaves the hollow — either
a pool in the bed or, with the water held at the floor, a channel of
water standing over the land beside it. The fill spans the valley's
cross-section rather than the bed alone, because a fill the bed's width
is a causeway with a cliff for a bank: a crater a cell wide dips hundreds
of meters under a floor, and that height over a bank of tens of meters
put the kernel four meters off the CPU at a float32 position. Over the
whole cross-section the same height is a fan a valley wide.
Where two valleys overlap the deeper cut and the taller fill each win, which at a confluence lays the tributary's floodplain over the trunk's as a cone that thins downstream faster than the trunk's floor drops.
The water is the floor over the bed, or the lake or sea that drowns the reach where that stands higher, and a lake's spill level over its floor, read as a kernel-weighted mean over the lake nodes within reach so one lake is one level exactly.
- graphDrainageGraph
- Undocumented
- lookupVec3
- Undocumented
- landformnumber
- Undocumented