to from distance and angle to a point (convert polar to cartesian coordinates)
x = cos( angle ) * distance;
y = sin( angle ) * distance;


from a point to angle and distance (convert cartesian to polar coordinates)
angle = atan2( y, x );
distance = dist( 0, 0, x, y );



now, if your center point isn't (0,0) but somewhere else, i.e. (cx,cy) the above
equations turn into:

x = cx + cos( angle ) * distance;
y = cy + sin( angle ) * distance;

angle = atan2( y - cy, x - cx );
distance = dist( cx, cy, x, y );

Thanks, After some tweaking it solved all my problems.