docs: private void addVirtualEdges(IntObjectMap<VirtualEdgeIterator> node2EdgeMap, EdgeFilter filter, boolean base,
                                   int node, int virtNode) {
          VirtualEdgeIterator existingIter = node2EdgeMap.get(node);
          if (existingIter == null) {
              existingIter = new VirtualEdgeIterator(10);
              node2EdgeMap.put(node, existingIter);
          }
          EdgeIteratorState edge = base
                  ? virtualEdges.get(virtNode * 4 + VE_BASE)
                  : virtualEdges.get(virtNode * 4 + VE_ADJ_REV);
          if (filter.accept(edge))
              existingIter.add(edge);
      }