private void rotateAroundPoint(Vector2 point, float delta)
{
var transform = control.transform;
var corners = control.GetCorners();
var plane = new Plane(corners[0], corners[1], corners[2]);
var ray = control.GetCamera().ScreenPointToRay(point);
var distance = 0f;
plane.Raycast(ray, out distance);
var worldAnchor = ray.GetPoint(distance);
var deltaAngle = new Vector3(0, 0, delta);
var angles = (transform.eulerAngles + deltaAngle);
var newPos = rotatePointAroundPivot(transform.position, worldAnchor, deltaAngle);
transform.position = newPos;
transform.eulerAngles = angles;
}