Svg.viewbox.matrix: def of gralha-svg-render@0.1.0.1
Import: import gralha-svg-render@0.1.0.1/svg.bend as Svg
Lines 2635-2649 of gralha-svg-render@0.1.0.1/svg.bend: https://jend.leeeet.dev/read.txt?path=gralha-svg-render@0.1.0.1/svg.bend&start_line=2635&end_line=2649

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

# SVG viewports establish local units and intersect their children with overflow clips.
def viewbox.matrix(+v: List<&2, F32>, +w: F32, +h: F32, +aspect: String) -> Matrix:
  +x = U.nth(v, 0n, 0.0)
  +y = U.nth(v, 1n, 0.0)
  +vw = U.nth(v, 2n, w)
  +vh = U.nth(v, 3n, h)
  +sx = (w / U.max(0.000001, vw) : F32)
  +sy = (h / U.max(0.000001, vh) : F32)
  +s = U.choose(F32, U.prefix(U.through(aspect, " "), "slice"), U.max(sx, sy), U.min(sx, sy))
  +tx = U.choose(F32, U.prefix(aspect, "xMin"), 0.0, U.choose(F32, U.prefix(aspect, "xMax"), 1.0, 0.5))
  +ty = U.choose(F32, U.prefix(U.drop(aspect, "xxxx"), "YMin"), 0.0,
    U.choose(F32, U.prefix(U.drop(aspect, "xxxx"), "YMax"), 1.0, 0.5))
  U.branch(Matrix, U.string.equal(aspect, "none"), _ => matrix.mul(scale(sx, sy), translate(F32.neg(x), F32.neg(y))),
    _ => matrix.mul(translate(((w - vw * s) * tx : F32), ((h - vh * s) * ty : F32)),
      matrix.mul(scale(s, s), translate(F32.neg(x), F32.neg(y)))))

Uses (20):
  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.mul
  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=Base/base.bend&name=String
  https://jend.leeeet.dev/definition.txt?path=gralha-svg-render@0.1.0.1/svg.bend&name=Matrix
  https://jend.leeeet.dev/definition.txt?path=gralha-svg-render@0.1.0.1/svg.bend&name=matrix.mul
  https://jend.leeeet.dev/definition.txt?path=gralha-svg-render@0.1.0.1/svg.bend&name=scale
  https://jend.leeeet.dev/definition.txt?path=gralha-svg-render@0.1.0.1/svg.bend&name=translate
  https://jend.leeeet.dev/definition.txt?path=gralha-text-scan@0.1.0.1/scan.bend&name=branch
  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=drop
  https://jend.leeeet.dev/definition.txt?path=gralha-text-scan@0.1.0.1/scan.bend&name=max
  https://jend.leeeet.dev/definition.txt?path=gralha-text-scan@0.1.0.1/scan.bend&name=min
  https://jend.leeeet.dev/definition.txt?path=gralha-text-scan@0.1.0.1/scan.bend&name=nth
  https://jend.leeeet.dev/definition.txt?path=gralha-text-scan@0.1.0.1/scan.bend&name=prefix
  https://jend.leeeet.dev/definition.txt?path=gralha-text-scan@0.1.0.1/scan.bend&name=string.equal
  https://jend.leeeet.dev/definition.txt?path=gralha-text-scan@0.1.0.1/scan.bend&name=through