code: protected int isBetter3D(Box a, Box b, Space space) {
  		int compare = Long.compare(a.getVolume(), b.getVolume());
  		if(compare != 0) {
  			return compare;
  		}
  		// determine lowest fit
  		a.fitRotate3DSmallestFootprint(space);
  		b.fitRotate3DSmallestFootprint(space);
  
  		return Long.compare(b.getFootprint(), a.getFootprint()); // i.e. smaller i better
  	}
docs: Is box b strictly better than a?
  
  @param a box
  @param b box
  @param space free space
  @return -1 if b is better, 0 if equal, 1 if b is better