code: void setRotate(double cosA, double sinA, Point2D rotationCenter) {
  		setShift(-rotationCenter.x, -rotationCenter.y);
  		Transformation2D temp = new Transformation2D();
  		temp.setRotate(cosA, sinA);
  		multiply(temp);
  		shift(rotationCenter.x, rotationCenter.y);
  	}
docs: Sets this transformation to be a rotation around point rotationCenter.
  
  When the axis Y is directed up and X is directed to the right, the
  positive angle corresponds to the anti-clockwise rotation. When the axis
  Y is directed down and X is directed to the right, the positive angle
  corresponds to the clockwise rotation.
  
  @param cosA
  The cos of the rotation angle.
  @param sinA
  The sin of the rotation angle.
  @param rotationCenter
  The center point of the rotation.