def tree.at

gralha-coverage@0.1.0.1 · cover.bend:56

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

56def tree.at(t: CovTree, +half: U32, +x: U32, +y: U32) -> F32:
57  match t:
58    case CovFlat{v}: v
59    case CovQuad{a, b, c, d}:
60      +left = U32.is_lt(x, half)
61      +top = U32.is_lt(y, half)
62      +xx = U.choose(U32, left, x, (x - half : U32))
63      +yy = U.choose(U32, top, y, (y - half : U32))
64      +next = U32.div(half, 2)
65      tree.at(U.choose(CovTree, top, U.choose(CovTree, left, a, b), U.choose(CovTree, left, c, d)), next, xx, yy)