bool
NBTrafficLightDefinition::foes(const NBEdge* const from1, const NBEdge* const to1,
                               const NBEdge* const from2, const NBEdge* const to2) const {
    if (to1 == 0 || to2 == 0) {
        return false;
    }
    // retrieve both nodes (it is possible that a connection
    std::vector<NBNode*>::const_iterator incoming =
        find_if(myControlledNodes.begin(), myControlledNodes.end(),
                NBContHelper::node_with_incoming_finder(from1));
    std::vector<NBNode*>::const_iterator outgoing =
        find_if(myControlledNodes.begin(), myControlledNodes.end(),
                NBContHelper::node_with_outgoing_finder(to1));
    assert(incoming != myControlledNodes.end());
    NBNode* incnode = *incoming;
    NBNode* outnode = *outgoing;
    if (incnode != outnode) {
        return false;
    }
    return incnode->foes(from1, to1, from2, to2);
}
bool
NBTrafficLightDefinition::forbids(const NBEdge* const possProhibitorFrom,
                                  const NBEdge* const possProhibitorTo,
                                  const NBEdge* const possProhibitedFrom,
                                  const NBEdge* const possProhibitedTo,
                                  bool regardNonSignalisedLowerPriority,
                                  bool sameNodeOnly) const {
    if (possProhibitorFrom == 0 || possProhibitorTo == 0 || possProhibitedFrom == 0 || possProhibitedTo == 0) {
        return false;
    }
    // retrieve both nodes
    std::vector<NBNode*>::const_iterator incoming =
        find_if(myControlledNodes.begin(), myControlledNodes.end(), NBContHelper::node_with_incoming_finder(possProhibitorFrom));
    std::vector<NBNode*>::const_iterator outgoing =
        find_if(myControlledNodes.begin(), myControlledNodes.end(), NBContHelper::node_with_outgoing_finder(possProhibitedTo));
    assert(incoming != myControlledNodes.end());
    NBNode* incnode = *incoming;
    NBNode* outnode = *outgoing;
    EdgeVector::const_iterator i;

    if (incnode != outnode) {
        if (sameNodeOnly) {
            return false;
        }
        // the links are located at different nodes
        const EdgeVector& ev1 = possProhibitedTo->getConnectedEdges();
        // go through the following edge,
        //  check whether one of these connections is prohibited
        for (i = ev1.begin(); i != ev1.end(); ++i) {
            std::vector<NBNode*>::const_iterator outgoing2 =
                find_if(myControlledNodes.begin(), myControlledNodes.end(), NBContHelper::node_with_outgoing_finder(*i));
            if (outgoing2 == myControlledNodes.end()) {
                continue;
            }
            NBNode* outnode2 = *outgoing2;
            if (incnode != outnode2) {
                continue;
            }
            if (incnode->getDirection(possProhibitedTo, *i) != LINKDIR_STRAIGHT) {
                continue;
            }
            bool ret1 = incnode->foes(possProhibitorFrom, possProhibitorTo,
                                      possProhibitedTo, *i);
            bool ret2 = incnode->forbids(possProhibitorFrom, possProhibitorTo,
                                         possProhibitedTo, *i,
                                         regardNonSignalisedLowerPriority);
            bool ret = ret1 || ret2;
            if (ret) {
                return true;
            }
        }

        const EdgeVector& ev2 = possProhibitorTo->getConnectedEdges();
        // go through the following edge,
        //  check whether one of these connections is prohibited
        for (i = ev2.begin(); i != ev2.end(); ++i) {
            std::vector<NBNode*>::const_iterator incoming2 =
                find_if(myControlledNodes.begin(), myControlledNodes.end(), NBContHelper::node_with_incoming_finder(possProhibitorTo));
            if (incoming2 == myControlledNodes.end()) {
                continue;
            }
            NBNode* incnode2 = *incoming2;
            if (incnode2 != outnode) {
                continue;
            }
            if (incnode2->getDirection(possProhibitorTo, *i) != LINKDIR_STRAIGHT) {
                continue;
            }
            bool ret1 = incnode2->foes(possProhibitorTo, *i,
                                       possProhibitedFrom, possProhibitedTo);
            bool ret2 = incnode2->forbids(possProhibitorTo, *i,
                                          possProhibitedFrom, possProhibitedTo,
                                          regardNonSignalisedLowerPriority);
            bool ret = ret1 || ret2;
            if (ret) {
                return true;
            }
        }
        return false;
    }
    // both links are located at the same node
    //  check using this node's information
    return incnode->forbids(possProhibitorFrom, possProhibitorTo,
                            possProhibitedFrom, possProhibitedTo,
                            regardNonSignalisedLowerPriority);
}