docs: private void shearY(Graphics g, int w1, int h1, Color color) {
  
  		int period = RandomUtil.randomInt(40) + 10; // 50;
  
  		boolean borderGap = true;
  		int frames = 20;
  		int phase = 7;
  		for (int i = 0; i < w1; i++) {
  			double d = (double) (period >> 1) * Math.sin((double) i / (double) period + (6.2831853071795862D * (double) phase) / (double) frames);
  			g.copyArea(i, 0, 1, h1, 0, (int) d);
  			if (borderGap) {
  				g.setColor(color);
  				g.drawLine(i, (int) d, i, 0);
  				g.drawLine(i, (int) d + h1, i, h1);
  			}
  
  		}
  
  	}