Visgraph.natural_sweep: def of bend-visgraph@2.0.0.0
Import: import bend-visgraph@2.0.0.0/visgraph.bend as Visgraph
Lines 697-716 of bend-visgraph@2.0.0.0/visgraph.bend: https://jend.leeeet.dev/read.txt?path=bend-visgraph@2.0.0.0/visgraph.bend&start_line=697&end_line=716

import Base

# The sweep of point a over the points right of it: ts2vg's inner loop. A
# point b the sweep sees replaces the smallest top and adds its edge at the
# next step, when `up` says so, so a step after an unseen point calls no
# def that recurses.
def natural_sweep(pts: Pts, up: Bool, +dir: Direction, +k: Weight, +lo: F32, +hi: F32, +ia: U32, +xa: F32, +ya: F32, +scale_a: F32, +ts: Tops, low: Low, +ib: U32, +xb: F32, +yb: F32, +sb: F32, es: Edges) -> Edges:
  match pts up:
    case PNil{} False{}:
      es
    case PNil{} True{}:
      natural_edge(dir, k, lo, hi, ia, ib, xa, xb, ya, yb, sb, scale_a, ts, es)
    case PCon{+ic, +xc, +yc, next} False{}:
      Low{+lk, +lv} = low
      +s = F32.div(F32.sub(yc, ya), F32.sub(xc, xa))
      natural_sweep(next, clears(F32.is_gt(s, lv), s, lv, scale_a, xc, yc), dir, k, lo, hi, ia, xa, ya, scale_a, ts, Low{lk, lv}, ic, xc, yc, s, es)
    case PCon{+ic, +xc, +yc, next} True{}:
      Low{+lk, lv} = low
      +after = set_at(lk, ts, sb)
      +now = lowest(after)
      +s = F32.div(F32.sub(yc, ya), F32.sub(xc, xa))
      natural_sweep(next, clears(F32.is_gt(s, Low.v(now)), s, Low.v(now), scale_a, xc, yc), dir, k, lo, hi, ia, xa, ya, scale_a, after, now, ic, xc, yc, s, natural_edge(dir, k, lo, hi, ia, ib, xa, xb, ya, yb, sb, scale_a, ts, es))

Uses (17):
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Bool
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=F32
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=F32.div
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=F32.is_gt
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=F32.sub
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=U32
  https://jend.leeeet.dev/definition.txt?path=bend-visgraph@2.0.0.0/visgraph.bend&name=Direction
  https://jend.leeeet.dev/definition.txt?path=bend-visgraph@2.0.0.0/visgraph.bend&name=Edges
  https://jend.leeeet.dev/definition.txt?path=bend-visgraph@2.0.0.0/visgraph.bend&name=Low
  https://jend.leeeet.dev/definition.txt?path=bend-visgraph@2.0.0.0/visgraph.bend&name=Low.v
  https://jend.leeeet.dev/definition.txt?path=bend-visgraph@2.0.0.0/visgraph.bend&name=Pts
  https://jend.leeeet.dev/definition.txt?path=bend-visgraph@2.0.0.0/visgraph.bend&name=Tops
  https://jend.leeeet.dev/definition.txt?path=bend-visgraph@2.0.0.0/visgraph.bend&name=Weight
  https://jend.leeeet.dev/definition.txt?path=bend-visgraph@2.0.0.0/visgraph.bend&name=clears
  https://jend.leeeet.dev/definition.txt?path=bend-visgraph@2.0.0.0/visgraph.bend&name=lowest
  https://jend.leeeet.dev/definition.txt?path=bend-visgraph@2.0.0.0/visgraph.bend&name=natural_edge
  https://jend.leeeet.dev/definition.txt?path=bend-visgraph@2.0.0.0/visgraph.bend&name=set_at