docs: public void getSet(int which , FastQueue<Point2D_I32> list ) {
  		list.reset();
  
  		BlockIndexLength set = sets.get(which);
  
  		for (int i = 0; i < set.length; i++) {
  			int index = set.start + i*2;
  			int blockIndex = set.block + index/blockLength;
  			index %= blockLength;
  
  			int block[] = blocks.get( blockIndex );
  			list.grow().set( block[index] , block[index+1] );
  		}
  	}