export function createPatchContext({ world, rects, candidateWindow, seed, patchAlpha, sourceIndexForWorld, worldIndex }) {
  const writeRect = rects?.writeRect;
  const writeCells = [];
  if (world && writeRect && typeof patchAlpha === "function" && typeof sourceIndexForWorld === "function" && typeof worldIndex === "function") {
    for (let y = writeRect.y0; y < writeRect.y1; y++) {
      for (let x = writeRect.x0; x < writeRect.x1; x++) {
        const wi = worldIndex(world, x, y);
        if (wi < 0) continue;
        const si = sourceIndexForWorld(rects, candidateWindow, x, y);
        if (si < 0) continue;
        const alpha = patchAlpha(x, y, rects, seed);
        if (alpha <= 0.005) continue;
        writeCells.push({ x, y, wi, si, alpha });
      }
    }
  }
  return {
    world,
    rects,
    candidateWindow,
    seed,
    writeCells,
  };
}