You can get pretty good results with just a little trigonometry. For example, in the diagram below, the ratio of angles A/(A+B) tells you how shaded the blue ti

You can get pretty good results with just a little trigonometry. For example, in the diagram below, the ratio of angles A/(A+B) tells you how shaded the blue tile should be. You can apply this method recursively. http://i.imgur.com/0rz69.png http://i.imgur.com/0rz69.png