// Left to right: 40x20 walls of sand, mixed rubble, and rubble with 20% clay.
// Capture at --ticks 0 and --ticks 180, --zoom 3 --no-light --freeze.
{
  const left = Math.max(4, SX - 400), floor = SY + 40;
  const rubble = [RSTONE, CUORE, FEORE, LDIRT];
  for (let x = left; x < left + 390; x++) {
    surfY[x] = floor; dirtY[x] = floor + 8;
    for (let y = floor - 90; y < floor + 8; y++) {
      bgm[y * W + x] = 0;
      setCell(y * W + x, y >= floor ? STONE : EMPTY, 20, y >= floor ? F_NAT : 0);
    }
  }
  for (let pile = 0; pile < 3; pile++) {
    const start = left + 60 + pile * 120;
    for (let y = floor - 40; y < floor; y++) for (let x = start; x < start + 20; x++) {
      const m = pile === 0 ? SAND : pile === 2 && (x + y) % 5 === 0 ? LCLAY : rubble[(x + y) % 4];
      setCell(y * W + x, m, 20, 0);
    }
  }
  updateRoof();
  window.CAM = [left + 195, floor - 24];
}