NIVissimConnectionCluster.cpp

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/****************************************************************************/
// -------------------
/****************************************************************************/
// SUMO, Simulation of Urban MObility; see http://sumo.dlr.de/
// Copyright (C) 2001-2017 DLR (http://www.dlr.de/) and contributors
/****************************************************************************/
//
//   This file is part of SUMO.
//   SUMO is free software: you can redistribute it and/or modify
//   it under the terms of the GNU General Public License as published by
//   the Free Software Foundation, either version 3 of the License, or
//   (at your option) any later version.
//
/****************************************************************************/


// ===========================================================================
// included modules
// ===========================================================================
#ifdef _MSC_VER
#include <windows_config.h>
#else
#include <config.h>
#endif

#include <algorithm>
#include <iostream>
#include <cassert>
#include <iterator>
#include <utils/geom/Boundary.h>
#include <utils/geom/GeomHelper.h>
#include <utils/common/VectorHelper.h>
#include <utils/common/MsgHandler.h>
#include <utils/common/ToString.h>
#include "NIVissimConnection.h"
#include "NIVissimDisturbance.h"
#include "NIVissimNodeCluster.h"
#include "NIVissimNodeDef.h"
#include "NIVissimEdge.h"
#include "NIVissimTL.h"
#include "NIVissimConnectionCluster.h"


// ===========================================================================
// static members
// ===========================================================================
NIVissimConnectionCluster::ContType NIVissimConnectionCluster::myClusters;
int NIVissimConnectionCluster::myFirstFreeID = 100000;
int NIVissimConnectionCluster::myStaticBlaID = 0;



// ===========================================================================
// method definitions
// ===========================================================================
// ---------------------------------------------------------------------------
// NIVissimConnectionCluster::NodeSubCluster - methods
// ---------------------------------------------------------------------------
NIVissimConnectionCluster::NodeSubCluster::NodeSubCluster(NIVissimConnection* c) {
    add(c);
}


NIVissimConnectionCluster::NodeSubCluster::~NodeSubCluster() {}


void
NIVissimConnectionCluster::NodeSubCluster::add(NIVissimConnection* c) {
    myBoundary.add(c->getBoundingBox());
    myConnections.push_back(c);
}


void
NIVissimConnectionCluster::NodeSubCluster::add(const NIVissimConnectionCluster::NodeSubCluster& c) {
    for (ConnectionCont::const_iterator i = c.myConnections.begin(); i != c.myConnections.end(); i++) {
        add(*i);
    }
}


int
NIVissimConnectionCluster::NodeSubCluster::size() const {
    return (int)myConnections.size();
}


std::vector<int>
NIVissimConnectionCluster::NodeSubCluster::getConnectionIDs() const {
    std::vector<int> ret;
    int id = NIVissimConnectionCluster::getNextFreeNodeID();
    for (ConnectionCont::const_iterator i = myConnections.begin(); i != myConnections.end(); i++) {
        ret.push_back((*i)->getID());
        (*i)->setNodeCluster(id);
    }
    return ret;
}


bool
NIVissimConnectionCluster::NodeSubCluster::overlapsWith(
    const NIVissimConnectionCluster::NodeSubCluster& c,
    double offset) {
    assert(myBoundary.xmax() >= myBoundary.xmin());
    assert(c.myBoundary.xmax() >= c.myBoundary.xmin());
    return myBoundary.overlapsWith(c.myBoundary, offset);
}



// ---------------------------------------------------------------------------
// NIVissimConnectionCluster - methods
// ---------------------------------------------------------------------------
NIVissimConnectionCluster::NIVissimConnectionCluster(
    const std::vector<int>& connections, int nodeCluster, int edgeid)
    : myConnections(connections), myNodeCluster(nodeCluster),
      myBlaID(myStaticBlaID++) {
    recomputeBoundary();
    myClusters.push_back(this);
    assert(edgeid > 0);
    if (edgeid >= 0) {
        myEdges.push_back(edgeid);
    }
    // add information about incoming and outgoing edges
    for (std::vector<int>::const_iterator i = connections.begin(); i != connections.end(); i++) {
        NIVissimConnection* c = NIVissimConnection::dictionary(*i);
        assert(c != 0);
        myOutgoingEdges.push_back(c->getToEdgeID());
        myIncomingEdges.push_back(c->getFromEdgeID());
        assert(c->getFromEdgeID() == edgeid || c->getToEdgeID() == edgeid);
    }
    VectorHelper<int>::removeDouble(myIncomingEdges);
    VectorHelper<int>::removeDouble(myOutgoingEdges);
}


NIVissimConnectionCluster::NIVissimConnectionCluster(
    const std::vector<int>& connections, const Boundary& boundary,
    int nodeCluster, const std::vector<int>& edges)
    : myConnections(connections), myBoundary(boundary),
      myNodeCluster(nodeCluster), myEdges(edges) {
    myClusters.push_back(this);
    recomputeBoundary();
    assert(myBoundary.xmax() >= myBoundary.xmin());
    // add information about incoming and outgoing edges
    for (std::vector<int>::const_iterator i = connections.begin(); i != connections.end(); i++) {
        NIVissimConnection* c = NIVissimConnection::dictionary(*i);
        assert(c != 0);
        myOutgoingEdges.push_back(c->getToEdgeID());
        myIncomingEdges.push_back(c->getFromEdgeID());
        assert(find(edges.begin(), edges.end(), c->getFromEdgeID()) != edges.end()
               ||
               find(edges.begin(), edges.end(), c->getToEdgeID()) != edges.end());
    }
    VectorHelper<int>::removeDouble(myIncomingEdges);
    VectorHelper<int>::removeDouble(myOutgoingEdges);
}


NIVissimConnectionCluster::~NIVissimConnectionCluster() {}



int
NIVissimConnectionCluster::getNextFreeNodeID() {
    return myFirstFreeID++;
}


bool
NIVissimConnectionCluster::overlapsWith(NIVissimConnectionCluster* c,
                                        double offset) const {
    assert(myBoundary.xmax() >= myBoundary.xmin());
    assert(c->myBoundary.xmax() >= c->myBoundary.xmin());
    return c->myBoundary.overlapsWith(myBoundary, offset);
}


void
NIVissimConnectionCluster::add(NIVissimConnectionCluster* c) {
    assert(myBoundary.xmax() >= myBoundary.xmin());
    assert(c->myBoundary.xmax() >= c->myBoundary.xmin());
    myBoundary.add(c->myBoundary);
    for (std::vector<int>::iterator i = c->myConnections.begin(); i != c->myConnections.end(); i++) {
        myConnections.push_back(*i);
    }
    VectorHelper<int>::removeDouble(myConnections);
    assert(myNodeCluster == -1 || c->myNodeCluster == -1);
    if (myNodeCluster == -1) {
        myNodeCluster = c->myNodeCluster;
    }
    // inform edges about merging
    //  !!! merge should be done within one method
    for (std::vector<int>::iterator j = c->myEdges.begin(); j != c->myEdges.end(); j++) {
        NIVissimEdge::dictionary(*j)->mergedInto(c, this);
    }
    copy(c->myEdges.begin(), c->myEdges.end(), back_inserter(myEdges));
    copy(c->myIncomingEdges.begin(), c->myIncomingEdges.end(),
         back_inserter(myIncomingEdges));
    copy(c->myOutgoingEdges.begin(), c->myOutgoingEdges.end(),
         back_inserter(myOutgoingEdges));
    VectorHelper<int>::removeDouble(myEdges);
    VectorHelper<int>::removeDouble(myIncomingEdges);
    VectorHelper<int>::removeDouble(myOutgoingEdges);
}



void
NIVissimConnectionCluster::joinBySameEdges(double offset) {
    // !!! ...
    // Further, we try to omit joining of overlaping nodes. This is done by holding
    //  the lists of incoming and outgoing edges and incrementally building the nodes
    //  regarding this information
    std::vector<NIVissimConnectionCluster*> joinAble;
    int pos = 0;
    ContType::iterator i = myClusters.begin();
    // step1 - faster but no complete
    while (i != myClusters.end()) {
        joinAble.clear();
        ContType::iterator j = i + 1;

        // check whether every combination has been processed
        while (j != myClusters.end()) {
            // check whether the current clusters overlap
            if ((*i)->joinable(*j, offset)) {
                joinAble.push_back(*j);
            }
            j++;
        }
        for (std::vector<NIVissimConnectionCluster*>::iterator k = joinAble.begin();
                k != joinAble.end(); k++) {
            // add the overlaping cluster
            (*i)->add(*k);
            // erase the overlaping cluster
            delete *k;
            myClusters.erase(find(myClusters.begin(), myClusters.end(), *k));
        }
        //
        if (joinAble.size() > 0) {
            i = myClusters.begin() + pos;
            // clear temporary storages
            joinAble.clear();
        } else {
            i++;
            pos++;
        }
    }
    //
    pos = 0;
    i = myClusters.begin();
    while (i != myClusters.end()) {
        ContType::iterator j = i + 1;
        // check whether every combination has been processed
        while (j != myClusters.end()) {
            // check whether the current clusters overlap
            if ((*i)->joinable(*j, offset)) {
                joinAble.push_back(*j);
            }
            j++;
        }
        for (std::vector<NIVissimConnectionCluster*>::iterator k = joinAble.begin();
                k != joinAble.end(); k++) {
            // add the overlaping cluster
            (*i)->add(*k);
            // erase the overlaping cluster
            delete *k;
            myClusters.erase(find(myClusters.begin(), myClusters.end(), *k));
        }
        //
        if (joinAble.size() > 0) {
            i = myClusters.begin();
            // clear temporary storages
            joinAble.clear();
            pos = 0;
        } else {
            i++;
            pos++;
        }
    }
    // check for weak district connections
    //  (junctions made up by district connections, where prohibitions are not
    //   modelled properly)
    pos = 0;
    i = myClusters.begin();
    while (i != myClusters.end()) {
        ContType::iterator j = i + 1;
        // check whether every combination has been processed
        while (j != myClusters.end()) {
            // check whether the current clusters overlap
            if ((*i)->isWeakDistrictConnRealisation(*j)) {
                joinAble.push_back(*j);
            }
            j++;
        }
        for (std::vector<NIVissimConnectionCluster*>::iterator k = joinAble.begin();
                k != joinAble.end(); k++) {
            // add the overlaping cluster
            (*i)->add(*k);
            // erase the overlaping cluster
            delete *k;
            myClusters.erase(find(myClusters.begin(), myClusters.end(), *k));
        }
        //
        if (joinAble.size() > 0) {
            i = myClusters.begin();
            // clear temporary storages
            joinAble.clear();
            pos = 0;
        } else {
            i++;
            pos++;
        }
    }
}


bool
NIVissimConnectionCluster::joinable(NIVissimConnectionCluster* c2, double offset) {
    // join clusters which have at least one connection in common
    if (VectorHelper<int>::subSetExists(myConnections, c2->myConnections)) {
        return true;
    }

    // connections shall overlap otherwise
    if (!overlapsWith(c2, offset)) {
        return false;
    }

    // at least one of the clusters shall not be assigned to a node in previous (!!!??)
    if (hasNodeCluster() && c2->hasNodeCluster()) {
        return false;
    }

    // join clusters which where connections do disturb each other
    if (VectorHelper<int>::subSetExists(c2->getDisturbanceParticipators(), myConnections)
            ||
            VectorHelper<int>::subSetExists(getDisturbanceParticipators(), c2->myConnections)) {

        return true;
    }


    // join clusters which do share the same incoming or outgoing edges (not mutually)
    std::vector<int> extendedOutgoing1;
    std::vector<int> extendedIncoming1;
    std::vector<int> extendedOutgoing2;
    std::vector<int> extendedIncoming2;
    if (myIncomingEdges.size() > 1 || c2->myIncomingEdges.size() > 1) {
        extendedOutgoing1 =
            extendByToTreatAsSame(myOutgoingEdges, myIncomingEdges);
        extendedIncoming1 =
            extendByToTreatAsSame(myIncomingEdges, myOutgoingEdges);
        extendedOutgoing2 =
            extendByToTreatAsSame(c2->myOutgoingEdges, c2->myIncomingEdges);
        extendedIncoming2 =
            extendByToTreatAsSame(c2->myIncomingEdges, c2->myOutgoingEdges);
    } else {
        extendedOutgoing1 = myIncomingEdges;
        extendedIncoming1 = myOutgoingEdges;
        extendedOutgoing2 = c2->myIncomingEdges;
        extendedIncoming2 = c2->myOutgoingEdges;
    }

    if (VectorHelper<int>::subSetExists(extendedOutgoing1, extendedOutgoing2)
            ||
            VectorHelper<int>::subSetExists(extendedIncoming1, extendedIncoming2)
       ) {
        return true;
    }
    return false;
}


bool
NIVissimConnectionCluster::isWeakDistrictConnRealisation(NIVissimConnectionCluster* c2) {
    if ((myIncomingEdges.size() == 1 && myOutgoingEdges.size() == 1)) {
        return false;
    }
    if ((c2->myIncomingEdges.size() == 1 && c2->myOutgoingEdges.size() == 1)) {
        return false;
    }

    // ok, may be the other way round
    if (myIncomingEdges.size() == 1 && c2->myOutgoingEdges.size() == 1) {
        return c2->isWeakDistrictConnRealisation(this);
    }
    // connections must cross
    bool crosses = false;
    for (std::vector<int>::const_iterator j1 = myConnections.begin(); j1 != myConnections.end() && !crosses; j1++) {
        NIVissimConnection* c1 = NIVissimConnection::dictionary(*j1);
        const PositionVector& g1 = c1->getGeometry();
        for (std::vector<int>::const_iterator j2 = c2->myConnections.begin(); j2 != c2->myConnections.end() && !crosses; j2++) {
            NIVissimConnection* c2 = NIVissimConnection::dictionary(*j2);
            const PositionVector& g2 = c2->getGeometry();
            if (g1.intersects(g2)) {
                crosses = true;
            }
        }
    }
    if (!crosses) {
        return false;
    }
    // ok, check for connection
    if (myOutgoingEdges.size() != 1 || c2->myIncomingEdges.size() != 1) {
        return false;
    }
    // check whether the connection is bidirectional
    NIVissimEdge* oe = NIVissimEdge::dictionary(myOutgoingEdges[0]);
    NIVissimEdge* ie = NIVissimEdge::dictionary(c2->myIncomingEdges[0]);
    if (oe == 0 || ie == 0) {
        return false;
    }
    return fabs(GeomHelper::angleDiff(oe->getGeometry().beginEndAngle(), ie->getGeometry().beginEndAngle())) < DEG2RAD(5);
}


bool
NIVissimConnectionCluster::liesOnSameEdgesEnd(NIVissimConnectionCluster* cc2) {
    //
    for (std::vector<int>::iterator i = myConnections.begin(); i != myConnections.end(); i++) {
        NIVissimConnection* c1 = NIVissimConnection::dictionary(*i);
        for (std::vector<int>::iterator j = cc2->myConnections.begin(); j != cc2->myConnections.end(); j++) {
            NIVissimConnection* c2 = NIVissimConnection::dictionary(*j);
            if (c1->getFromEdgeID() == c2->getFromEdgeID()) {
                NIVissimEdge* e = NIVissimEdge::dictionary(c1->getFromEdgeID());
                const PositionVector& g = e->getGeometry();
                double pos1 = GeomHelper::nearest_offset_on_line_to_point2D(
                                  g.front(), g.back(), c1->getBoundary().getCenter());
                double pos2 = GeomHelper::nearest_offset_on_line_to_point2D(
                                  g.front(), g.back(), c2->getBoundary().getCenter());
                if (pos1 <= 5.0 && pos2 <= 5.0) {
                    return true;
                }
            }
            if (c1->getToEdgeID() == c2->getToEdgeID()) {
                NIVissimEdge* e = NIVissimEdge::dictionary(c1->getFromEdgeID());
                const PositionVector& g = e->getGeometry();
                double pos1 = GeomHelper::nearest_offset_on_line_to_point2D(
                                  g.front(), g.back(), c1->getBoundary().getCenter());
                double pos2 = GeomHelper::nearest_offset_on_line_to_point2D(
                                  g.front(), g.back(), c2->getBoundary().getCenter());
                if (pos1 >= g.length() - 5.0 && pos2 >= g.length() - 5.0) {
                    return true;
                }
            }
        }
    }
    return false;
}


std::vector<int>
NIVissimConnectionCluster::extendByToTreatAsSame(const std::vector<int>& iv1,
        const std::vector<int>& iv2) const {
    std::vector<int> ret(iv1);
    for (std::vector<int>::const_iterator i = iv1.begin(); i != iv1.end(); i++) {
        NIVissimEdge* e = NIVissimEdge::dictionary(*i);
        const std::vector<NIVissimEdge*> treatAsSame = e->getToTreatAsSame();
        for (std::vector<NIVissimEdge*>::const_iterator j = treatAsSame.begin(); j != treatAsSame.end(); j++) {
            if (find(iv2.begin(), iv2.end(), (*j)->getID()) == iv2.end()) {
                ret.push_back((*j)->getID());
            }
        }
    }
    return ret;
}

std::vector<int>
NIVissimConnectionCluster::getDisturbanceParticipators() {
    std::vector<int> ret;
    for (std::vector<int>::iterator i = myConnections.begin(); i != myConnections.end(); i++) {
        NIVissimConnection* c = NIVissimConnection::dictionary(*i);
        const std::vector<int>& disturbances = c->getDisturbances();
        for (std::vector<int>::const_iterator j = disturbances.begin(); j != disturbances.end(); j++) {
            NIVissimDisturbance* d = NIVissimDisturbance::dictionary(*j);
            ret.push_back(d->getEdgeID());
            ret.push_back(d->getDisturbanceID());
        }
    }
    return ret;
}


void
NIVissimConnectionCluster::buildNodeClusters() {
    for (ContType::iterator i = myClusters.begin(); i != myClusters.end(); i++) {
        std::vector<int> disturbances;
        std::vector<int> tls;
        std::vector<int> nodes;
        int tlsid = -1;
        int nodeid = -1;
        if ((*i)->myConnections.size() > 0) {
            (*i)->recomputeBoundary();
            disturbances = NIVissimDisturbance::getWithin((*i)->myBoundary);
        }
        nodes = (*i)->myNodes;//NIVissimTL::getWithin((*i)->myBoundary, 5.0);
        if (nodes.size() > 1) {
            WRITE_WARNING("NIVissimConnectionCluster:More than a single node");
            //          throw 1; // !!! eigentlich sollte hier nur eine Ampelanlage sein
        }
        if (nodes.size() > 0) {
            nodeid = nodes[0];
        }
        //
        //
        int id = NIVissimNodeCluster::dictionary(
                     nodeid, tlsid, (*i)->myConnections,
                     disturbances, (*i)->myIncomingEdges.size() < 2);
        assert((*i)->myNodeCluster == id || (*i)->myNodeCluster < 0);
        (*i)->myNodeCluster = id;
    }
}


void
NIVissimConnectionCluster::_debugOut(std::ostream& into) {
    for (ContType::iterator i = myClusters.begin(); i != myClusters.end(); i++) {
        std::vector<int> connections = (*i)->myConnections;
        for (std::vector<int>::iterator j = connections.begin(); j != connections.end(); j++) {
            if (j != connections.begin()) {
                into << ", ";
            }
            into << *j;
        }
        into << "(" << (*i)->myBoundary << ")" << std::endl;
    }
    into << "---------------------------" << std::endl;
}



bool
NIVissimConnectionCluster::hasNodeCluster() const {
    return myNodeCluster != -1;
}


int
NIVissimConnectionCluster::dictSize() {
    return (int)myClusters.size();
}


void
NIVissimConnectionCluster::removeConnections(const NodeSubCluster& c) {
    for (NodeSubCluster::ConnectionCont::const_iterator i = c.myConnections.begin(); i != c.myConnections.end(); i++) {
        NIVissimConnection* conn = *i;
        int connid = conn->getID();
        std::vector<int>::iterator j = find(myConnections.begin(), myConnections.end(), connid);
        if (j != myConnections.end()) {
            myConnections.erase(j);
        }
    }
    recomputeBoundary();
}


void
NIVissimConnectionCluster::recomputeBoundary() {
    myBoundary = Boundary();
    for (std::vector<int>::iterator i = myConnections.begin(); i != myConnections.end(); i++) {
        NIVissimConnection* c = NIVissimConnection::dictionary(*i);
        if (c != 0) {
            myBoundary.add(c->getFromGeomPosition());
            myBoundary.add(c->getToGeomPosition());
            if (c->getGeometry().size() != 0) {
                myBoundary.add(c->getGeometry().getBoxBoundary());
            }
        }
    }
    assert(myBoundary.xmax() >= myBoundary.xmin());
}


NBNode*
NIVissimConnectionCluster::getNBNode() const {
    return NIVissimNodeCluster::dictionary(myNodeCluster)->getNBNode();
}


bool
NIVissimConnectionCluster::around(const Position& p, double offset) const {
    assert(myBoundary.xmax() >= myBoundary.xmin());
    return myBoundary.around(p, offset);
}



void
NIVissimConnectionCluster::recheckEdges() {
    assert(myConnections.size() != 0);
    // remove the cluster from all edges at first
    std::vector<int>::iterator i;
    for (i = myEdges.begin(); i != myEdges.end(); i++) {
        NIVissimEdge* edge = NIVissimEdge::dictionary(*i);
        edge->removeFromConnectionCluster(this);
    }
    // clear edge information
    myEdges.clear();
    // recheck which edges do still participate and add edges
    for (i = myConnections.begin(); i != myConnections.end(); i++) {
        NIVissimConnection* c = NIVissimConnection::dictionary(*i);
        assert(myBoundary.xmax() >= myBoundary.xmin());
        if (myBoundary.around(c->getFromGeomPosition(), 5)) {
            myEdges.push_back(c->getFromEdgeID());
        }
        assert(myBoundary.xmax() >= myBoundary.xmin());
        if (myBoundary.around(c->getToGeomPosition(), 5)) {
            myEdges.push_back(c->getToEdgeID());
        }
    }
    // connect edges
    for (i = myEdges.begin(); i != myEdges.end(); i++) {
        NIVissimEdge* edge = NIVissimEdge::dictionary(*i);
        edge->addToConnectionCluster(this);
    }
}


double
NIVissimConnectionCluster::getPositionForEdge(int edgeid) const {
    // return the middle of the connections when there are any
    if (myConnections.size() != 0) {
        double sum = 0;
        int part = 0;
        std::vector<int>::const_iterator i;
        for (i = myConnections.begin(); i != myConnections.end(); i++) {
            NIVissimConnection* c = NIVissimConnection::dictionary(*i);
            if (c->getFromEdgeID() == edgeid) {
                part++;
                sum += c->getFromPosition();
            }
            if (c->getToEdgeID() == edgeid) {
                part++;
                sum += c->getToPosition();
            }
        }
        if (part > 0) {
            return sum / (double) part;
        }
    }
    // use the position of the node if possible
    if (myNodeCluster >= 0) {
        // try to find the nearest point on the edge
        //  !!! only the main geometry is regarded
        NIVissimNodeDef* node =
            NIVissimNodeDef::dictionary(myNodeCluster);
        if (node != 0) {
            double pos = node->getEdgePosition(edgeid);
            if (pos >= 0) {
                return pos;
            }
        }
        /*
                double try1 = GeomHelper::nearest_offset_on_line_to_point(
                    edge->getBegin2D(), edge->getEnd2D(), node->getPos());
                if(try1>=0) {
                    return try1;
                }
                // try to use simple distance
                double dist1 =
                    GeomHelper::distance(node->getPos(), edge->getBegin2D());
                double dist2 =
                    GeomHelper::distance(node->getPos(), edge->getEnd2D());
                return dist1<dist2
                    ? 0 : edge->getLength();
                    */
    }
    // what else?
    WRITE_WARNING("NIVissimConnectionCluster: how to get an edge's position?");
    // !!!
    assert(myBoundary.xmin() <= myBoundary.xmax());
    NIVissimEdge* edge = NIVissimEdge::dictionary(edgeid);
    std::vector<int>::const_iterator i = find(myEdges.begin(), myEdges.end(), edgeid);
    if (i == myEdges.end()) {
        // edge does not exist!?
        throw 1;
    }
    const PositionVector& edgeGeom = edge->getGeometry();
    Position p = GeomHelper::crossPoint(myBoundary, edgeGeom);
    return GeomHelper::nearest_offset_on_line_to_point2D(
               edgeGeom.front(), edgeGeom.back(), p);
}



void
NIVissimConnectionCluster::clearDict() {
    for (ContType::iterator i = myClusters.begin(); i != myClusters.end(); i++) {
        delete(*i);
    }
    myClusters.clear();
    myFirstFreeID = 100000;
}


PositionVector
NIVissimConnectionCluster::getIncomingContinuationGeometry(NIVissimEdge* e) const {
    // collect connection where this edge is the incoming one
    std::vector<NIVissimConnection*> edgeIsIncoming;
    for (std::vector<int>::const_iterator i = myConnections.begin(); i != myConnections.end(); i++) {
        NIVissimConnection* c = NIVissimConnection::dictionary(*i);
        if (c->getFromEdgeID() == e->getID()) {
            edgeIsIncoming.push_back(c);
        }
    }
    //
    if (edgeIsIncoming.size() == 0) {
        return PositionVector();
    }
    // sort connected edges in same direction
    sort(edgeIsIncoming.begin(), edgeIsIncoming.end(),
         same_direction_sorter(e->getGeometry().beginEndAngle()));
    NIVissimConnection* c = *(edgeIsIncoming.begin());
    return c->getGeometry();
}



NIVissimConnection*
NIVissimConnectionCluster::getIncomingContinuation(NIVissimEdge* e) const {
    // collect connection where this edge is the incoming one
    std::vector<NIVissimConnection*> edgeIsIncoming;
    for (std::vector<int>::const_iterator i = myConnections.begin(); i != myConnections.end(); i++) {
        NIVissimConnection* c = NIVissimConnection::dictionary(*i);
        if (c->getFromEdgeID() == e->getID()) {
            edgeIsIncoming.push_back(c);
        }
    }
    //
    if (edgeIsIncoming.size() == 0) {
        return 0;
    }
    // sort connected edges in same direction
    sort(edgeIsIncoming.begin(), edgeIsIncoming.end(),
         same_direction_sorter(e->getGeometry().beginEndAngle()));
    return *(edgeIsIncoming.begin());
}



PositionVector
NIVissimConnectionCluster::getOutgoingContinuationGeometry(NIVissimEdge* e) const {
    // collect connection where this edge is the outgoing one
    std::vector<NIVissimConnection*> edgeIsOutgoing;
    for (std::vector<int>::const_iterator i = myConnections.begin(); i != myConnections.end(); i++) {
        NIVissimConnection* c = NIVissimConnection::dictionary(*i);
        if (c->getToEdgeID() == e->getID()) {
            edgeIsOutgoing.push_back(c);
        }
    }
    //
    if (edgeIsOutgoing.size() == 0) {
        return PositionVector();
    }
    // sort connected edges in same direction
    sort(edgeIsOutgoing.begin(), edgeIsOutgoing.end(),
         same_direction_sorter(e->getGeometry().beginEndAngle()));
    NIVissimConnection* c = *(edgeIsOutgoing.begin());
    return c->getGeometry();
}


NIVissimConnection*
NIVissimConnectionCluster::getOutgoingContinuation(NIVissimEdge* e) const {
    // collect connection where this edge is the outgoing one
    std::vector<NIVissimConnection*> edgeIsOutgoing;
    for (std::vector<int>::const_iterator i = myConnections.begin(); i != myConnections.end(); i++) {
        NIVissimConnection* c = NIVissimConnection::dictionary(*i);
        if (c->getToEdgeID() == e->getID()) {
            edgeIsOutgoing.push_back(c);
        }
    }
    //
    if (edgeIsOutgoing.size() == 0) {
        return 0;
    }
    // sort connected edges in same direction
    sort(edgeIsOutgoing.begin(), edgeIsOutgoing.end(),
         same_direction_sorter(e->getGeometry().beginEndAngle()));
    return *(edgeIsOutgoing.begin());
}



/****************************************************************************/