sclass RegionBoundingBoxPainter > RegionPainter {
  settable int lineWidth = 3;

  void drawRegion {
    Rect r = bounds();
    g.setColor(withOpacity(.75, Color.red));
    temp tempSetStroke(g, new BasicStroke(lineWidth));
    drawRect(g, growRectTopAndLeft(scaleRect_floor(growRectRightAndBottom(r), zoomX, zoomY)));
  }
}