private Rectangle getSelectionRectangle() {
    if (isAltOptionPressed()) {
      // Alt/Option: Center selection around starting point
      int deltaX = Math.abs(myStartScreenX - myCurrentScreenX);
      int deltaY = Math.abs(myStartScreenY - myCurrentScreenY);
      return new Rectangle(myStartScreenX - deltaX, myStartScreenY - deltaY, 2 * deltaX, 2 * deltaY);
    }

    // Select diagonally from upper left to lower right
    return new Rectangle(myStartScreenX, myStartScreenY, 0, 0).union(new Rectangle(myCurrentScreenX, myCurrentScreenY, 0, 0));
  }
private Rectangle getSelectionRectangle()