My next step in implementing my algorithm in Java is following.
It is quite difficult to explain, but I know what I need. I have this equation:
Given: d
Asked: $\alpha$
$(1-\cos\alpha)^2 + \sin^2\alpha = d^2 $
Which I "simplified" to this, using this formula's:
$2+2\cos\alpha+\frac{\cos2\alpha}{2}-\frac{\sin\alpha}{2} = d^2$
But now, I'm stuck. This is probably pretty easy, but I'm 15 years old at the moment. I didn't see that much trigonometry in school yet.
Can you help me?