static BufferedImage renderBackgroundPlusBoxes_withHints(int w, int h, BackgroundPlusBoxes s) {
  BufferedImage bi = renderBackgroundPlusBoxes(w, h, s);
  for (BoxWithColor e : s.boxes) {
    int x1 = min(e.a.x, e.b.x), y1 = min(e.a.y, e.b.y);
    int x2 = max(e.a.x, e.b.x), y2 = max(e.a.y, e.b.y);
    drawRect(g, x1, y1, x2-x1+1, y2-y1+1, colorWithAlpha(0.5, Color.black));
  }
  ret bi;
}