How to calculate position on a circle with a certain angle?

Question

I\'m trying to figure out how I could be able to calculate coordinates on a circle. For simplicity I made some images.

Answer 1

One elegant way to accomplish this is using complex numbers, available for example here.

In pseudo-code:

z = (x_old + I*y_old)*exp(I*angle);
x_new = real(z);
y_new = imag(z);

NOTE: the rotation angle needs to be in radians. NOTE2: this assumes a circle centred at (0,0). Just add a shift if the center is not there.