// Transform rotated rectangle while dragging bottom-right handle
		// The top-left point will not move!
		// For a rectangle with top-left at x, y
		// A = top-left point (A' after rotation)
		// C = bottom-right point (C' after rotation)
		public void AdjustRectangle(Rectangle rectangle, Point bottomRight, float angle) {
			// Establish the center of the rectangle cx, cy
			var center = new PointF(
				rectangle.X + rectangle.Width / 2,
				 rectangle.Y + rectangle.Height / 2
			);
			// Get rotated top-left point
			var rotatedA = rotate(rectangle.Location, center, angle);
			// Get the new center by finding the midpoint between A' and C'.
			var newCenter = new PointF(
				(rotatedA.X+ bottomRight.X) / 2,
				(rotatedA.Y + bottomRight.Y) / 2
			);
			// Get new top-left and new bottom-right points
			var newTopLeft = rotate(rotatedA,newCenter,-angle );
			var newBottomRight = rotate(bottomRight,newCenter,-angle );

			// Rotate point A(x,y) around center cx, cy by angle
			// return A' (rotated top-left)
			PointF rotate(PointF p, PointF c, double a) {
				return new PointF().Set(
					(p.X - c.X) * Math.Cos(a) - (p.Y - c.Y) * Math.Sin(a) + c.X,
					(p.X - c.X) * Math.Sin(a) + (p.Y - c.Y) * Math.Cos(a) + c.Y
				);
			}

			// Apply new transform on rotated Rectangle
			rectangle.Location = newTopLeft.ToPoint();
			rectangle.Size = new SizeF(
				newBottomRight.X - newTopLeft.X,
				newBottomRight.Y - newTopLeft.Y
			).ToSize();
		}