static BufferedImage renderShape(Color bg default Color.white, Shape shape, int w, int h) {
  BufferedImage img = newBufferedImage(w, h, bg);
  Graphics2D g = img.createGraphics();
  g.setColor(Color.black);
  g.fill(shape);
  ret img;
}

static BufferedImage renderShape(Color bg default Color.white, Shape shape, Rect bounds) {
  BufferedImage img = newBufferedImage(bounds.w, bounds.h, bg);
  Graphics2D g = img.createGraphics();
  g.translate(-bounds.x, -bounds.y);
  g.setColor(Color.black);
  g.fill(shape);
  ret img;
}