	@Test
	public void graphics_test(){

		Img img = new Img(400, 400);
		img.paint(g->{
			g.setColor(new Color(0xffff0000));
			g.drawLine(0, 0, 400, 400);
		});
		img.forEach(px->{
			if(px.getX() == px.getY()){
				assertEquals(0xffff0000, px.getValue());
			} else {
				assertEquals(0, px.getValue());
			}
		});
	}