Cover.act.add: def of gralha-coverage@0.1.0.1
Import: import gralha-coverage@0.1.0.1/cover.bend as Cover
Lines 288-298 of gralha-coverage@0.1.0.1/cover.bend: https://jend.leeeet.dev/read.txt?path=gralha-coverage@0.1.0.1/cover.bend&start_line=288&end_line=298

import Base
import gralha-text-scan@0.1.0.1/scan.bend as U

# A line covers [top, bottom) so a shared vertex counts once; a horizontal line
# never crosses. Lines whose bottom the scanline has passed are dropped.
def act.add(l: CovLine, +sy: F32, acc: List<&2, Act>) -> List<&2, Act>:
  CovLine{x0, y0, x1, y1} = l
  +ax = x0
  +ay = y0
  +bx = x1
  +by = y1
  +up = F32.is_lt(ay, by)
  +bottom = U.max(ay, by)
  act.keep(F32.is_lt(sy, bottom) && Bool.not(F32.is_eq(ay, by)), ax, ay, ((bx - ax) / (by - ay) : F32), bottom, U.choose(F32, up, 1.0, F32.neg(1.0)), sy, acc)

Uses (14):
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Bool.and
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Bool.not
  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_eq
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=F32.is_lt
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=F32.neg
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=F32.sub
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=List
  https://jend.leeeet.dev/definition.txt?path=gralha-coverage@0.1.0.1/cover.bend&name=Act
  https://jend.leeeet.dev/definition.txt?path=gralha-coverage@0.1.0.1/cover.bend&name=CovLine
  https://jend.leeeet.dev/definition.txt?path=gralha-coverage@0.1.0.1/cover.bend&name=act.keep
  https://jend.leeeet.dev/definition.txt?path=gralha-text-scan@0.1.0.1/scan.bend&name=choose
  https://jend.leeeet.dev/definition.txt?path=gralha-text-scan@0.1.0.1/scan.bend&name=max