NBAlgorithms.cpp

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// Eclipse SUMO, Simulation of Urban MObility; see https://eclipse.org/sumo
// Copyright (C) 2012-2018 German Aerospace Center (DLR) and others.
// This program and the accompanying materials
// are made available under the terms of the Eclipse Public License v2.0
// which accompanies this distribution, and is available at
// http://www.eclipse.org/legal/epl-v20.html
// SPDX-License-Identifier: EPL-2.0
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// Algorithms for network computation
/****************************************************************************/


// ===========================================================================
// included modules
// ===========================================================================
#include <config.h>

#include <sstream>
#include <iostream>
#include <cassert>
#include <algorithm>
#include <utils/common/MsgHandler.h>
#include <utils/common/ToString.h>
#include "NBEdge.h"
#include "NBNodeCont.h"
#include "NBTypeCont.h"
#include "NBNode.h"
#include "NBAlgorithms.h"


// ===========================================================================
// method definitions
// ===========================================================================
// ---------------------------------------------------------------------------
// NBTurningDirectionsComputer
// ---------------------------------------------------------------------------
void
NBTurningDirectionsComputer::computeTurnDirections(NBNodeCont& nc, bool warn) {
    for (std::map<std::string, NBNode*>::const_iterator i = nc.begin(); i != nc.end(); ++i) {
        computeTurnDirectionsForNode(i->second, warn);
    }
}

void
NBTurningDirectionsComputer::computeTurnDirectionsForNode(NBNode* node, bool warn) {
    const std::vector<NBEdge*>& incoming = node->getIncomingEdges();
    const std::vector<NBEdge*>& outgoing = node->getOutgoingEdges();
    // reset turning directions since this may be called multiple times
    for (std::vector<NBEdge*>::const_iterator k = incoming.begin(); k != incoming.end(); ++k) {
        (*k)->setTurningDestination(0);
    }
    std::vector<Combination> combinations;
    for (std::vector<NBEdge*>::const_iterator j = outgoing.begin(); j != outgoing.end(); ++j) {
        NBEdge* outedge = *j;
        for (std::vector<NBEdge*>::const_iterator k = incoming.begin(); k != incoming.end(); ++k) {
            NBEdge* e = *k;
            // @todo: check whether NBHelpers::relAngle is properly defined and whether it should really be used, here
            const double signedAngle = NBHelpers::normRelAngle(e->getAngleAtNode(node), outedge->getAngleAtNode(node));
            if (signedAngle > 0 && signedAngle < 177 && e->getGeometry().back().distanceTo2D(outedge->getGeometry().front()) < POSITION_EPS) {
                // backwards curving edges can only be turnaround when there are
                // non-default endpoints
                continue;
            }
            double angle = fabs(signedAngle);
            // std::cout << "incoming=" << e->getID() << " outgoing=" << outedge->getID() << " relAngle=" << NBHelpers::relAngle(e->getAngleAtNode(node), outedge->getAngleAtNode(node)) << "\n";
            if (e->getFromNode() == outedge->getToNode() && angle > 120) {
                // they connect the same nodes; should be the turnaround direction
                // we'll assign a maximum number
                //
                // @todo: indeed, we have observed some pathological intersections
                //  see "294831560" in OSM/adlershof. Here, several edges are connecting
                //  same nodes. We have to do the angle check before...
                //
                // @todo: and well, there are some other as well, see plain import
                //  of delphi_muenchen (elmar), intersection "59534191". Not that it would
                //  be realistic in any means; we will warn, here.
                angle += 360;
            }
            if (angle < 160) {
                continue;
            }
            Combination c;
            c.from = e;
            c.to = outedge;
            c.angle = angle;
            combinations.push_back(c);
        }
    }
    // sort combinations so that the ones with the highest angle are at the begin
    std::sort(combinations.begin(), combinations.end(), combination_by_angle_sorter());
    std::set<NBEdge*> seen;
    for (std::vector<Combination>::const_iterator j = combinations.begin(); j != combinations.end(); ++j) {
        if (seen.find((*j).from) != seen.end() || seen.find((*j).to) != seen.end()) {
            // do not regard already set edges
            if ((*j).angle > 360 && warn) {
                WRITE_WARNING("Ambiguity in turnarounds computation at junction '" + node->getID() + "'.");
                warn = false;
            }
            continue;
        }
        // mark as seen
        seen.insert((*j).from);
        seen.insert((*j).to);
        // set turnaround information
        bool onlyPossible = (*j).from->getConnections().size() != 0 && !(*j).from->isConnectedTo((*j).to);
        //std::cout << "    setTurningDestination from=" << (*j).from->getID() << " to=" << (*j).to->getID() << " onlyPossible=" << onlyPossible << "\n";
        (*j).from->setTurningDestination((*j).to, onlyPossible);
    }
}


// ---------------------------------------------------------------------------
// NBNodesEdgesSorter
// ---------------------------------------------------------------------------
void
NBNodesEdgesSorter::sortNodesEdges(NBNodeCont& nc, bool useNodeShape) {
    for (std::map<std::string, NBNode*>::const_iterator i = nc.begin(); i != nc.end(); ++i) {
        i->second->sortEdges(useNodeShape);
    }
}


void
NBNodesEdgesSorter::swapWhenReversed(const NBNode* const n,
                                     const std::vector<NBEdge*>::iterator& i1,
                                     const std::vector<NBEdge*>::iterator& i2) {
    NBEdge* e1 = *i1;
    NBEdge* e2 = *i2;
    // @todo: The difference between "isTurningDirectionAt" and "isTurnaround"
    //  is not nice. Maybe we could get rid of it if we would always mark edges
    //  as turnarounds, even if they do not have to be added, as mentioned in
    //  notes on NBTurningDirectionsComputer::computeTurnDirectionsForNode
    if (e2->getToNode() == n && e2->isTurningDirectionAt(e1)) {
        std::swap(*i1, *i2);
    }
}


// ---------------------------------------------------------------------------
// NBNodeTypeComputer
// ---------------------------------------------------------------------------
void
NBNodeTypeComputer::computeNodeTypes(NBNodeCont& nc) {
    validateRailCrossings(nc);
    for (std::map<std::string, NBNode*>::const_iterator i = nc.begin(); i != nc.end(); ++i) {
        NBNode* n = (*i).second;
        // the type may already be set from the data
        if (n->myType != NODETYPE_UNKNOWN && n->myType != NODETYPE_DEAD_END) {
            continue;
        }
        // check whether the node is a waterway node. Set to unregulated by default
        bool waterway = true;
        for (EdgeVector::const_iterator i = n->getEdges().begin(); i != n->getEdges().end(); ++i) {
            if (!isWaterway((*i)->getPermissions())) {
                waterway = false;
                break;
            }
        }
        if (waterway && (n->myType == NODETYPE_UNKNOWN || n->myType == NODETYPE_DEAD_END)) {
            n->myType = NODETYPE_NOJUNCTION;
            continue;
        }

        // check whether the junction is not a real junction
        if (n->myIncomingEdges.size() == 1) {
            n->myType = NODETYPE_PRIORITY;
            continue;
        }
        // @todo "isSimpleContinuation" should be revalidated
        if (n->isSimpleContinuation()) {
            n->myType = NODETYPE_PRIORITY;
            continue;
        }
        // determine the type
        SumoXMLNodeType type = NODETYPE_RIGHT_BEFORE_LEFT;
        for (EdgeVector::const_iterator i = n->myIncomingEdges.begin(); i != n->myIncomingEdges.end(); i++) {
            for (EdgeVector::const_iterator j = i + 1; j != n->myIncomingEdges.end(); j++) {
                // @todo "getOppositeIncoming" should probably be refactored into something the edge knows
                if (n->getOppositeIncoming(*j) == *i && n->myIncomingEdges.size() > 2) {
                    continue;
                }
                // @todo check against a legal document
                // @todo figure out when NODETYPE_PRIORITY_STOP is appropriate
                const double s1 = (*i)->getSpeed() * (double) 3.6;
                const double s2 = (*j)->getSpeed() * (double) 3.6;
                const int p1 = (*i)->getPriority();
                const int p2 = (*j)->getPriority();
                if (fabs(s1 - s2) > (double) 9.5 || MAX2(s1, s2) >= (double) 49. || p1 != p2) {
                    type = NODETYPE_PRIORITY;
                    break;
                }
            }
        }
        // save type
        n->myType = type;
    }
}


void
NBNodeTypeComputer::validateRailCrossings(NBNodeCont& nc) {
    for (std::map<std::string, NBNode*>::const_iterator i = nc.begin(); i != nc.end(); ++i) {
        NBNode* n = (*i).second;
        if (n->myType == NODETYPE_RAIL_CROSSING) {
            // check if it really is a rail crossing
            int numRailway = 0;
            int numNonRailway = 0;
            int numNonRailwayNonPed = 0;
            for (NBEdge* e : n->getIncomingEdges()) {
                if ((e->getPermissions() & ~SVC_RAIL_CLASSES) != 0) {
                    numNonRailway++;
                    if (e->getPermissions() != SVC_PEDESTRIAN) {
                        numNonRailwayNonPed++;
                    }
                } else if ((e->getPermissions() & SVC_RAIL_CLASSES) != 0) {
                    numRailway++;
                }
            }
            for (NBEdge* e : n->getOutgoingEdges()) {
                if (e->getPermissions() == SVC_PEDESTRIAN) {
                    numNonRailway++;
                }
            }
            if (numNonRailway == 0 || numRailway == 0) {
                // not a crossing (maybe unregulated or rail_signal)
                n->myType = NODETYPE_PRIORITY;
            } else if (numNonRailwayNonPed > 2) {
                // does not look like a rail crossing (roads in conflict). maybe a traffic light?
                n->myType = NODETYPE_PRIORITY;
            }
        }
    }
}


bool
NBNodeTypeComputer::isRailwayNode(NBNode* n) {
    int numRailway = 0;
    int numNonRailway = 0;
    for (NBEdge* e : n->getIncomingEdges()) {
        if ((e->getPermissions() & ~SVC_RAIL_CLASSES) != 0) {
            numNonRailway++;
        } else if ((e->getPermissions() & SVC_RAIL_CLASSES) != 0) {
            numRailway++;
        }
    }
    return numRailway > 0 && numNonRailway == 0;
}

// ---------------------------------------------------------------------------
// NBEdgePriorityComputer
// ---------------------------------------------------------------------------
void
NBEdgePriorityComputer::computeEdgePriorities(NBNodeCont& nc) {
    for (std::map<std::string, NBNode*>::const_iterator i = nc.begin(); i != nc.end(); ++i) {
        computeEdgePrioritiesSingleNode((*i).second);
    }
}


void
NBEdgePriorityComputer::computeEdgePrioritiesSingleNode(NBNode* node) {
    // preset all junction's edge priorities to zero
    for (EdgeVector::iterator j = node->myAllEdges.begin(); j != node->myAllEdges.end(); ++j) {
        (*j)->setJunctionPriority(node, NBEdge::MINOR_ROAD);
    }
    node->markBentPriority(false);
    // check if the junction is not a real junction
    if (node->myIncomingEdges.size() == 1 && node->myOutgoingEdges.size() == 1) {
        return;
    }
    // compute the priorities on junction when needed
    if (node->getType() != NODETYPE_RIGHT_BEFORE_LEFT) {
        setPriorityJunctionPriorities(*node);
    }
}


void
NBEdgePriorityComputer::setPriorityJunctionPriorities(NBNode& n) {
    if (n.myIncomingEdges.size() == 0 || n.myOutgoingEdges.size() == 0) {
        return;
    }
    EdgeVector incoming = n.myIncomingEdges;
    EdgeVector outgoing = n.myOutgoingEdges;
    // what we do want to have is to extract the pair of roads that are
    //  the major roads for this junction
    // let's get the list of incoming edges with the highest priority
    std::sort(incoming.begin(), incoming.end(), NBContHelper::edge_by_priority_sorter());
    EdgeVector bestIncoming;
    NBEdge* best = incoming[0];
    while (incoming.size() > 0 && samePriority(best, incoming[0])) {
        bestIncoming.push_back(*incoming.begin());
        incoming.erase(incoming.begin());
    }
    // now, let's get the list of best outgoing
    assert(outgoing.size() != 0);
    sort(outgoing.begin(), outgoing.end(), NBContHelper::edge_by_priority_sorter());
    EdgeVector bestOutgoing;
    best = outgoing[0];
    while (outgoing.size() > 0 && samePriority(best, outgoing[0])) { //->getPriority()==best->getPriority()) {
        bestOutgoing.push_back(*outgoing.begin());
        outgoing.erase(outgoing.begin());
    }
    // special case: user input makes mainDirection unambiguous
    const bool mainDirectionExplicit = (
                                           bestIncoming.size() == 1 && n.myIncomingEdges.size() <= 2
                                           && (incoming.size() == 0 || bestIncoming[0]->getPriority() > incoming[0]->getPriority())
                                           && bestOutgoing.size() == 1 && n.myOutgoingEdges.size() <= 2
                                           && (outgoing.size() == 0 || bestOutgoing[0]->getPriority() > outgoing[0]->getPriority())
                                           && !bestIncoming[0]->isTurningDirectionAt(bestOutgoing[0]));
    // now, let's compute for each of the best incoming edges
    //  the incoming which is most opposite
    //  the outgoing which is most opposite
    EdgeVector::iterator i;
    std::map<NBEdge*, NBEdge*> counterIncomingEdges;
    std::map<NBEdge*, NBEdge*> counterOutgoingEdges;
    incoming = n.myIncomingEdges;
    outgoing = n.myOutgoingEdges;
    for (i = bestIncoming.begin(); i != bestIncoming.end(); ++i) {
        std::sort(incoming.begin(), incoming.end(), NBContHelper::edge_opposite_direction_sorter(*i, &n, true));
        counterIncomingEdges[*i] = *incoming.begin();
        std::sort(outgoing.begin(), outgoing.end(), NBContHelper::edge_opposite_direction_sorter(*i, &n, true));
        counterOutgoingEdges[*i] = *outgoing.begin();
    }
    //std::cout << "n=" << n.getID() << " best=" << best->getID() << " bestIncoming=" << toString(bestIncoming) << "\n incoming=" << toString(incoming) << "\n outgoing=" << toString(outgoing) << "\n mainExplicit=" << mainDirectionExplicit << " counterBest=" << counterIncomingEdges.find(bestIncoming[0])->second->getID() << "\n";
    // ok, let's try
    // 1) there is one best incoming road
    if (bestIncoming.size() == 1) {
        // let's mark this road as the best
        NBEdge* best1 = extractAndMarkFirst(n, bestIncoming);
        if (!mainDirectionExplicit && counterIncomingEdges.find(best1) != counterIncomingEdges.end()) {
            // ok, look, what we want is the opposit of the straight continuation edge
            // but, what if such an edge does not exist? By now, we'll determine it
            // geometrically
            NBEdge* s = counterIncomingEdges.find(best1)->second;
            const double minAngleDiff = GeomHelper::getMinAngleDiff(best1->getAngleAtNode(&n), s->getAngleAtNode(&n));
            if (minAngleDiff > 180 - 45
                    || (minAngleDiff > 75 && s->getPriority() == best1->getPriority() && hasDifferentPriorities(incoming, best1))) {
                s->setJunctionPriority(&n, NBEdge::PRIORITY_ROAD);
            }
        }
        markBestParallel(n, best1, 0);
        assert(bestOutgoing.size() != 0);
        // mark the best outgoing as the continuation
        sort(bestOutgoing.begin(), bestOutgoing.end(), NBContHelper::edge_similar_direction_sorter(best1));
        // assign extra priority if the priorities are unambiguous (regardless of geometry)
        NBEdge* bestOut = extractAndMarkFirst(n, bestOutgoing);
        if (!mainDirectionExplicit && counterOutgoingEdges.find(bestOut) != counterOutgoingEdges.end()) {
            NBEdge* s = counterOutgoingEdges.find(bestOut)->second;
            if (GeomHelper::getMinAngleDiff(bestOut->getAngleAtNode(&n), s->getAngleAtNode(&n)) > 180 - 45) {
                s->setJunctionPriority(&n, 1);
            }
        }
        n.markBentPriority(n.getDirection(best1, bestOut) != LINKDIR_STRAIGHT);
        return;
    }

    // ok, what we want to do in this case is to determine which incoming
    //  has the best continuation...
    // This means, when several incoming roads have the same priority,
    //  we want a (any) straight connection to be more priorised than a turning
    double bestAngle = 0;
    NBEdge* bestFirst = 0;
    NBEdge* bestSecond = 0;
    bool hadBest = false;
    for (i = bestIncoming.begin(); i != bestIncoming.end(); ++i) {
        EdgeVector::iterator j;
        NBEdge* t1 = *i;
        double angle1 = t1->getAngleAtNode(&n) + 180;
        if (angle1 >= 360) {
            angle1 -= 360;
        }
        for (j = i + 1; j != bestIncoming.end(); ++j) {
            NBEdge* t2 = *j;
            double angle2 = t2->getAngleAtNode(&n) + 180;
            if (angle2 >= 360) {
                angle2 -= 360;
            }
            double angle = GeomHelper::getMinAngleDiff(angle1, angle2);
            if (!hadBest || angle > bestAngle) {
                bestAngle = angle;
                bestFirst = *i;
                bestSecond = *j;
                hadBest = true;
            }
        }
    }
    bestFirst->setJunctionPriority(&n, 1);
    sort(bestOutgoing.begin(), bestOutgoing.end(), NBContHelper::edge_similar_direction_sorter(bestFirst));
    if (bestOutgoing.size() != 0) {
        extractAndMarkFirst(n, bestOutgoing);
    }
    bestSecond->setJunctionPriority(&n, 1);
    sort(bestOutgoing.begin(), bestOutgoing.end(), NBContHelper::edge_similar_direction_sorter(bestSecond));
    if (bestOutgoing.size() != 0) {
        extractAndMarkFirst(n, bestOutgoing);
    }
    n.markBentPriority(GeomHelper::getMinAngleDiff(bestFirst->getAngleAtNode(&n), bestSecond->getAngleAtNode(&n)) < 135);
    markBestParallel(n, bestFirst, bestSecond);
}

void
NBEdgePriorityComputer::markBestParallel(const NBNode& n, NBEdge* bestFirst, NBEdge* bestSecond) {
    // edges running parallel to the main direction should also be prioritised
    const double a1 = bestFirst->getAngleAtNode(&n);
    const double a2 = bestSecond == 0 ? a1 : bestSecond->getAngleAtNode(&n);
    SVCPermissions p1 = bestFirst->getPermissions();
    SVCPermissions p2 = bestSecond == 0 ? p1 : bestSecond->getPermissions();
    for (NBEdge* e : n.getIncomingEdges()) {
        // @note: this rule might also apply if there are common permissions but
        // then we would not further rules to resolve the priority between the best edge and its parallel edge
        SVCPermissions perm = e->getPermissions();
        if (((GeomHelper::getMinAngleDiff(e->getAngleAtNode(&n), a1) < 10
                || GeomHelper::getMinAngleDiff(e->getAngleAtNode(&n), a2) < 10))
                && (p1 & perm) == 0 && (p2 & perm) == 0) {
            e->setJunctionPriority(&n, 1);
        }
    }
}


NBEdge*
NBEdgePriorityComputer::extractAndMarkFirst(NBNode& n, std::vector<NBEdge*>& s, int prio) {
    if (s.size() == 0) {
        return 0;
    }
    NBEdge* ret = s.front();
    s.erase(s.begin());
    ret->setJunctionPriority(&n, prio);
    return ret;
}


bool
NBEdgePriorityComputer::samePriority(const NBEdge* const e1, const NBEdge* const e2) {
    if (e1 == e2) {
        return true;
    }
    if (e1->getPriority() != e2->getPriority()) {
        return false;
    }
    if ((int) e1->getSpeed() != (int) e2->getSpeed()) {
        return false;
    }
    return (int) e1->getNumLanes() == (int) e2->getNumLanes();
}


bool
NBEdgePriorityComputer::hasDifferentPriorities(const EdgeVector& edges, const NBEdge* excluded) {
    if (edges.size() < 2) {
        return false;
    }
    int prio = edges[0] == excluded ? edges[1]->getPriority() : edges[0]->getPriority();
    for (auto e : edges) {
        if (e != excluded && e->getPriority() != prio) {
            return true;
        }
    }
    return false;
}


NBNodesEdgesSorter::crossing_by_junction_angle_sorter::crossing_by_junction_angle_sorter(const NBNode* node, const EdgeVector& ordering) {
    // reorder based on getAngleAtNodeToCenter
    myOrdering = ordering;
    sort(myOrdering.begin(), myOrdering.end(), NBContHelper::edge_by_angle_to_nodeShapeCentroid_sorter(node));
    // let the first edge remain the first
    rotate(myOrdering.begin(), std::find(myOrdering.begin(), myOrdering.end(), ordering.front()), myOrdering.end());
}


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