예제 #1
0
void ElementGeometryClipper::visitWay(const Way& way)
{
    ClipperLib::Path wayShape;
    PointLocation pointLocation = setPath(quadKeyBbox_, way, wayShape);
    // 1. all geometry inside current quadkey: no need to truncate.
    if (pointLocation == PointLocation::AllInside) {
        callback_(way, quadKey_);
        return;
    }

    // 2. all geometry outside : way should be skipped
    if (pointLocation == PointLocation::AllOutside) {
        return;
    }

    ClipperLib::PolyTree solution;
    clipper_.AddPath(wayShape, ClipperLib::ptSubject, false);
    clipper_.AddPath(createPathFromBoundingBox(), ClipperLib::ptClip, true);
    clipper_.Execute(ClipperLib::ctIntersection, solution);
    clipper_.Clear();
    std::size_t count = static_cast<std::size_t>(solution.Total());

    // 3. way intersects border only once: store a copy with clipped geometry
    if (count == 1) {
        Way clippedWay;
        setData(clippedWay, way, solution.GetFirst()->Contour);
        callback_(clippedWay, quadKey_);
    }
        // 4. in this case, result should be stored as relation (collection of ways)
    else {
        Relation relation;
        relation.id = way.id;
        relation.tags = way.tags;
        relation.elements.reserve(count);
        ClipperLib::PolyNode* polyNode = solution.GetFirst();
        while (polyNode) {
            auto clippedWay = std::make_shared<Way>();
            clippedWay->id = way.id;
            setCoordinates(*clippedWay, polyNode->Contour);
            relation.elements.push_back(clippedWay);
            polyNode = polyNode->GetNext();
        }
        callback_(relation, quadKey_);
    }
}
예제 #2
0
void ElementGeometryClipper::visitRelation(const Relation& relation)
{
    struct RelationVisitor : public ElementVisitor
    {
        RelationVisitor(const BoundingBox& quadKeyBbox, ClipperLib::Clipper& clipper) :
                bbox_(quadKeyBbox), clipper_(clipper) { }

        void visitNode(const Node& node) 
        {
            // TODO
        }

        void visitWay(const Way& way)
        {
            ClipperLib::Path wayShape;
            setPath(bbox_, way, wayShape);
            clipper_.AddPath(wayShape, ClipperLib::ptSubject, false);
        }

        void visitArea(const Area& area)
        {
            ClipperLib::Path areaShape;
            setPath(bbox_, area, areaShape);
            clipper_.AddPath(areaShape, ClipperLib::ptSubject, true);
        }

        void visitRelation(const Relation& relation)
        {
            for (const auto& element : relation.elements) {
                element->accept(*this);
            }
        }

    private:
        const BoundingBox& bbox_;
        ClipperLib::Clipper& clipper_;

    } visitor(quadKeyBbox_, clipper_);

    relation.accept(visitor);

    // Process results
    ClipperLib::PolyTree solution;
    clipper_.AddPath(createPathFromBoundingBox(), ClipperLib::ptClip, true);
    clipper_.Execute(ClipperLib::ctIntersection, solution);
    clipper_.Clear();

    std::size_t count = static_cast<size_t>(solution.Total());
    // Do not store one result as relation
    if (count == 1) {
        ClipperLib::PolyNode* node = solution.GetFirst();
        if (node->IsOpen()) {
            Way way;
            setData(way, relation, node->Contour);
            callback_(way, quadKey_);
        }
        else {
            if (!node->IsHole()) {
                Area area;
                setData(area, relation, node->Contour);
                callback_(area, quadKey_);
            }
        }
    }
    else if (count > 1) {
        Relation newRelation;
        newRelation.id = relation.id;
        newRelation.tags = relation.tags;
        newRelation.elements.reserve(count);

        ClipperLib::PolyNode* polyNode = solution.GetFirst();
        while (polyNode) {
            if (polyNode->IsOpen()) {
                auto way = std::make_shared<Way>();
                setCoordinates(*way, polyNode->Contour);
                newRelation.elements.push_back(way);
            }
            else {
                auto area = std::make_shared<Area>();
                setCoordinates(*area, polyNode->Contour);
                newRelation.elements.push_back(area);
            }
            polyNode = polyNode->GetNext();
        }
        callback_(newRelation, quadKey_);
    }
}