Co-ordinates of the four points of a uiview which has been rotated
CGPoint topLeft = view.bounds.origin;
topLeft = [[view superview] convertPoint:topLeft fromView:view];

CGPoint topRight = CGPointMake(view.bounds.origin.x + view.bounds.width, view.bounds.origin.y);
topRight = [[view superview] convertPoint:topRight fromView:view];

// ... likewise for the other points