code: public void setFrameFromCenter (float centerX, float centerY,
                                      float cornerX, float cornerY) {
          float width = Math.abs(cornerX - centerX);
          float height = Math.abs(cornerY - centerY);
          setFrame(centerX - width, centerY - height, width * 2, height * 2);
      }
docs: Sets the location and size of the framing rectangle of this shape based on the specified
  center and corner points.