Dirkometrix shows you the permitted error in a Basketball shot under a given incident angle. It gives you the option to select a Ball size 7 or size 6. It shows you the original basket, the ellipse of the tilted basket (under the given incident angle), the permitted error without the ball touching the rim (swish), the permitted error with the ball touching the rim and the osculating circle of the ellipse of the tilted basket.You can change the incident angle of the ball to see the change of the error.