docs: protected void defineSmallRectangle(ZoomableGraphicsContext gc, T element) {
  		final double ptsSize = element.getPointSize() / 2.;
  		final double x = element.getX() - ptsSize;
  		final double y = element.getY() - ptsSize;
  		final double mx = element.getX() + ptsSize;
  		final double my = element.getY() + ptsSize;
  		gc.moveTo(x, y);
  		gc.lineTo(mx, y);
  		gc.lineTo(mx, my);
  		gc.lineTo(x, my);
  		gc.closePath();
  	}