CGPoint CGPointMake(CGFloat x, CGFloat y);
bool CGPointEqualToPoint(CGPoint point1, CGPoint point2)
CGPointZero
bool CGRectContainsPoint(CGRect rect, CGPoint point)
CGPoint getVector(CGPoint p1, CGPoint p2) { return CGPointMake(p2.x - p1.x, p2.y - p1.y); }
float getDistance(CGPoint p) { return sqrtf((p.x)*(p.x) + (p.y)*(p.y)); }