private int getImageWidthToUse() {
    assert myCurrentImage != null;
    if (!myHorizontal) {
      return myCurrentImage.getWidth();
    }
    
    int sign = myExpand ? 1 : -1;
    int result = myCurrentImage.getWidth() + sign * myAnimationIterationStep;

    if (result <= 0 || result > myImage.getWidth()) {
      return -1;
    }
    return result;
  }
private int getImageWidthToUse()