C++ PolygonRef::add方法代码示例

void addLineInfill(Polygons& result, PointMatrix matrix, int scanline_min_idx, int lineSpacing, AABB boundary, std::vector<std::vector<int64_t> > cutList, int extrusionWidth)
{
    auto addLine = [&](Point from, Point to)
    {            
        PolygonRef p = result.newPoly();
        p.add(matrix.unapply(from));
        p.add(matrix.unapply(to));
    };
    
    auto compare_int64_t = [](const void* a, const void* b)
    {
        int64_t n = (*(int64_t*)a) - (*(int64_t*)b);
        if (n < 0) return -1;
        if (n > 0) return 1;
        return 0;
    };
    
    int scanline_idx = 0;
    for(int64_t x = scanline_min_idx * lineSpacing; x < boundary.max.X; x += lineSpacing)
    {
        qsort(cutList[scanline_idx].data(), cutList[scanline_idx].size(), sizeof(int64_t), compare_int64_t);
        for(unsigned int i = 0; i + 1 < cutList[scanline_idx].size(); i+=2)
        {
            if (cutList[scanline_idx][i+1] - cutList[scanline_idx][i] < extrusionWidth / 5)
                continue;
            addLine(Point(x, cutList[scanline_idx][i]), Point(x, cutList[scanline_idx][i+1]));
        }
        scanline_idx += 1;
    }
}

void FffPolygonGenerator::processFuzzyWalls(SliceMeshStorage& mesh)
{
    if (mesh.getSettingAsCount("wall_line_count") == 0)
    {
        return;
    }
    int64_t fuzziness = mesh.getSettingInMicrons("magic_fuzzy_skin_thickness");
    int64_t avg_dist_between_points = mesh.getSettingInMicrons("magic_fuzzy_skin_point_dist");
    int64_t min_dist_between_points = avg_dist_between_points * 3 / 4; // hardcoded: the point distance may vary between 3/4 and 5/4 the supplied value
    int64_t range_random_point_dist = avg_dist_between_points / 2;
    for (unsigned int layer_nr = 0; layer_nr < mesh.layers.size(); layer_nr++)
    {
        SliceLayer& layer = mesh.layers[layer_nr];
        for (SliceLayerPart& part : layer.parts)
        {
            Polygons results;
            Polygons& skin = (mesh.getSettingAsSurfaceMode("magic_mesh_surface_mode") == ESurfaceMode::SURFACE)? part.outline : part.insets[0];
            for (PolygonRef poly : skin)
            {
                // generate points in between p0 and p1
                PolygonRef result = results.newPoly();
                
                int64_t dist_left_over = rand() % (min_dist_between_points / 2); // the distance to be traversed on the line before making the first new point
                Point* p0 = &poly.back();
                for (Point& p1 : poly)
                { // 'a' is the (next) new point between p0 and p1
                    Point p0p1 = p1 - *p0;
                    int64_t p0p1_size = vSize(p0p1);    
                    int64_t dist_last_point = dist_left_over + p0p1_size * 2; // so that p0p1_size - dist_last_point evaulates to dist_left_over - p0p1_size
                    for (int64_t p0pa_dist = dist_left_over; p0pa_dist < p0p1_size; p0pa_dist += min_dist_between_points + rand() % range_random_point_dist)
                    {
                        int r = rand() % (fuzziness * 2) - fuzziness;
                        Point perp_to_p0p1 = turn90CCW(p0p1);
                        Point fuzz = normal(perp_to_p0p1, r);
                        Point pa = *p0 + normal(p0p1, p0pa_dist) + fuzz;
                        result.add(pa);
                        dist_last_point = p0pa_dist;
                    }
                    dist_left_over = p0p1_size - dist_last_point;
                    
                    p0 = &p1;
                }
                while (result.size() < 3 )
                {
                    unsigned int point_idx = poly.size() - 2;
                    result.add(poly[point_idx]);
                    if (point_idx == 0) { break; }
                    point_idx--;
                }
                if (result.size() < 3)
                {
                    result.clear();
                    for (Point& p : poly)
                        result.add(p);
                }
            }
            skin = results;
        }
    }
}

void FffPolygonGenerator::processInsets(SliceMeshStorage& mesh, unsigned int layer_nr) 
{
    SliceLayer* layer = &mesh.layers[layer_nr];
    if (mesh.getSettingAsSurfaceMode("magic_mesh_surface_mode") != ESurfaceMode::SURFACE)
    {
        int inset_count = mesh.getSettingAsCount("wall_line_count");
        if (mesh.getSettingBoolean("magic_spiralize") && static_cast<int>(layer_nr) < mesh.getSettingAsCount("bottom_layers") && layer_nr % 2 == 1)//Add extra insets every 2 layers when spiralizing, this makes bottoms of cups watertight.
            inset_count += 5;
        int line_width_x = mesh.getSettingInMicrons("wall_line_width_x");
        int line_width_0 = mesh.getSettingInMicrons("wall_line_width_0");
        if (mesh.getSettingBoolean("alternate_extra_perimeter"))
            inset_count += layer_nr % 2; 
        bool recompute_outline_based_on_outer_wall = mesh.getSettingBoolean("support_enable");
        WallsComputation walls_computation(mesh.getSettingInMicrons("wall_0_inset"), line_width_0, line_width_x, inset_count, recompute_outline_based_on_outer_wall);
        walls_computation.generateInsets(layer);
    }
    if (mesh.getSettingAsSurfaceMode("magic_mesh_surface_mode") != ESurfaceMode::NORMAL)
    {
        for (PolygonRef polyline : layer->openPolyLines)
        {
            Polygons segments;
            for (unsigned int point_idx = 1; point_idx < polyline.size(); point_idx++)
            {
                PolygonRef segment = segments.newPoly();
                segment.add(polyline[point_idx-1]);
                segment.add(polyline[point_idx]);
            }
        }
    }
}

void PrimeTower::generateGroundpoly(const SliceDataStorage& storage)
{
    extruder_count = storage.meshgroup->getExtruderCount();

    int64_t prime_tower_wall_thickness = storage.getSettingInMicrons("prime_tower_wall_thickness");
    int64_t tower_size = storage.getSettingInMicrons("prime_tower_size");

    if (prime_tower_wall_thickness * 2 < tower_size)
    {
        is_hollow = true;
    }

    PolygonRef p = ground_poly.newPoly();
    int tower_distance = 0; 
    int x = storage.getSettingInMicrons("prime_tower_position_x"); // storage.model_max.x
    int y = storage.getSettingInMicrons("prime_tower_position_y"); // storage.model_max.y
    p.add(Point(x + tower_distance, y + tower_distance));
    p.add(Point(x + tower_distance, y + tower_distance + tower_size));
    p.add(Point(x + tower_distance - tower_size, y + tower_distance + tower_size));
    p.add(Point(x + tower_distance - tower_size, y + tower_distance));
    middle = Point(x - tower_size / 2, y + tower_size / 2);

    if (is_hollow)
    {
        ground_poly = ground_poly.difference(ground_poly.offset(-prime_tower_wall_thickness));
    }

    post_wipe_point = Point(x + tower_distance - tower_size / 2, y + tower_distance + tower_size / 2);
}

void generateLineInfill(const Polygons& in_outline, Polygons& result, int extrusionWidth, int lineSpacing, int infillOverlap, double rotation)
{
    Polygons outline = in_outline.offset(extrusionWidth * infillOverlap / 100);
    PointMatrix matrix(rotation);
    
    outline.applyMatrix(matrix);
    
    AABB boundary(outline);
    
    boundary.min.X = ((boundary.min.X / lineSpacing) - 1) * lineSpacing;
    int lineCount = (boundary.max.X - boundary.min.X + (lineSpacing - 1)) / lineSpacing;
    vector<vector<int64_t> > cutList;
    for(int n=0; n<lineCount; n++)
        cutList.push_back(vector<int64_t>());

    for(unsigned int polyNr=0; polyNr < outline.size(); polyNr++)
    {
        Point p1 = outline[polyNr][outline[polyNr].size()-1];
        for(unsigned int i=0; i < outline[polyNr].size(); i++)
        {
            Point p0 = outline[polyNr][i];
            int idx0 = (p0.X - boundary.min.X) / lineSpacing;
            int idx1 = (p1.X - boundary.min.X) / lineSpacing;
            int64_t xMin = p0.X, xMax = p1.X;
            if (p0.X > p1.X) { xMin = p1.X; xMax = p0.X; }
            if (idx0 > idx1) { int tmp = idx0; idx0 = idx1; idx1 = tmp; }
            for(int idx = idx0; idx<=idx1; idx++)
            {
                int x = (idx * lineSpacing) + boundary.min.X + lineSpacing / 2;
                if (x < xMin) continue;
                if (x >= xMax) continue;
                int y = p0.Y + (p1.Y - p0.Y) * (x - p0.X) / (p1.X - p0.X);
                cutList[idx].push_back(y);
            }
            p1 = p0;
        }
    }
    
    int idx = 0;
    for(int64_t x = boundary.min.X + lineSpacing / 2; x < boundary.max.X; x += lineSpacing)
    {
        std::sort(cutList[idx].begin(), cutList[idx].end());
        for(unsigned int i = 0; i + 1 < cutList[idx].size(); i+=2)
        {
            if (cutList[idx][i+1] - cutList[idx][i] < extrusionWidth / 5)
                continue;
            PolygonRef p = result.newPoly();
            p.add(matrix.unapply(Point(x, cutList[idx][i])));
            p.add(matrix.unapply(Point(x, cutList[idx][i+1])));
        }
        idx += 1;
    }
}

void PrimeTower::generateGroundpoly(SliceDataStorage& storage) 
{
    PolygonRef p = storage.primeTower.ground_poly.newPoly();
    int tower_size = storage.getSettingInMicrons("prime_tower_size");
    int tower_distance = 0; 
    int x = storage.getSettingInMicrons("prime_tower_position_x"); // storage.model_max.x
    int y = storage.getSettingInMicrons("prime_tower_position_y"); // storage.model_max.y
    p.add(Point(x + tower_distance, y + tower_distance));
    p.add(Point(x + tower_distance, y + tower_distance + tower_size));
    p.add(Point(x + tower_distance - tower_size, y + tower_distance + tower_size));
    p.add(Point(x + tower_distance - tower_size, y + tower_distance));

    storage.wipePoint = Point(x + tower_distance - tower_size / 2, y + tower_distance + tower_size / 2);   
}

void ListPolyIt::convertListPolygonToPolygon(ListPolygon& list_polygon, PolygonRef polygon)
{
    for (Point& p : list_polygon)
    {
        polygon.add(p);
    }
}

void WallOverlapComputation::convertListPolygonToPolygon(ListPolygon& poly, PolygonRef result)
{
    result.clear();
    for (Point& p : poly)
    {
        result.add(p);
    }
}

void AreaSupport::handleWallStruts(
    Polygons& supportLayer_this,
    int supportMinAreaSqrt,
    int supportTowerDiameter
    )
{
    for (unsigned int p = 0; p < supportLayer_this.size(); p++)
    {
        PolygonRef poly = supportLayer_this[p];
        if (poly.size() < 6) // might be a single wall
        {
            PolygonRef poly = supportLayer_this[p];
            int best = -1;
            int best_length2 = -1;
            for (unsigned int i = 0; i < poly.size(); i++)
            {
                int length2 = vSize2(poly[i] - poly[(i+1) % poly.size()]);
                if (length2 > best_length2)
                {
                    best = i;
                    best_length2 = length2;
                }
            }
            
            if (best_length2 < supportMinAreaSqrt * supportMinAreaSqrt)
                break; // this is a small area, not a wall!
                
            
            // an estimate of the width of the area
            int width = sqrt( poly.area() * poly.area() / best_length2 ); // sqrt (a^2 / l^2) instead of a / sqrt(l^2)
            
            // add square tower (strut) in the middle of the wall
            if (width < supportMinAreaSqrt)
            {
                Point mid = (poly[best] + poly[(best+1) % poly.size()] ) / 2;
                Polygons struts;
                PolygonRef strut = struts.newPoly();
                strut.add(mid + Point( supportTowerDiameter/2,  supportTowerDiameter/2));
                strut.add(mid + Point(-supportTowerDiameter/2,  supportTowerDiameter/2));
                strut.add(mid + Point(-supportTowerDiameter/2, -supportTowerDiameter/2));
                strut.add(mid + Point( supportTowerDiameter/2, -supportTowerDiameter/2));
                supportLayer_this = supportLayer_this.unionPolygons(struts);
            }
        }
    }
}

void PrimeTower::generatePaths_OLD(SliceDataStorage& storage, unsigned int total_layers)
{
    
    if (storage.max_object_height_second_to_last_extruder >= 0 && storage.getSettingBoolean("prime_tower_enable"))
    {
        PolygonRef p = storage.primeTower.ground_poly.newPoly();
        int tower_size = storage.getSettingInMicrons("prime_tower_size");
        int tower_distance = 0; 
        int x = storage.getSettingInMicrons("prime_tower_position_x"); // storage.model_max.x
        int y = storage.getSettingInMicrons("prime_tower_position_y"); // storage.model_max.y
        p.add(Point(x + tower_distance, y + tower_distance));
        p.add(Point(x + tower_distance, y + tower_distance + tower_size));
        p.add(Point(x + tower_distance - tower_size, y + tower_distance + tower_size));
        p.add(Point(x + tower_distance - tower_size, y + tower_distance));

        storage.wipePoint = Point(x + tower_distance - tower_size / 2, y + tower_distance + tower_size / 2);
    }
}

void FffPolygonGenerator::processInsets(SliceDataStorage& storage, unsigned int layer_nr) 
{
    for(SliceMeshStorage& mesh : storage.meshes)
    {
        SliceLayer* layer = &mesh.layers[layer_nr];
        if (mesh.getSettingAsSurfaceMode("magic_mesh_surface_mode") != ESurfaceMode::SURFACE)
        {
            int inset_count = mesh.getSettingAsCount("wall_line_count");
            if (mesh.getSettingBoolean("magic_spiralize") && static_cast<int>(layer_nr) < mesh.getSettingAsCount("bottom_layers") && layer_nr % 2 == 1)//Add extra insets every 2 layers when spiralizing, this makes bottoms of cups watertight.
                inset_count += 5;
            int line_width_x = mesh.getSettingInMicrons("wall_line_width_x");
            int line_width_0 = mesh.getSettingInMicrons("wall_line_width_0");
            if (mesh.getSettingBoolean("alternate_extra_perimeter"))
                inset_count += layer_nr % 2; 
            generateInsets(layer, mesh.getSettingInMicrons("machine_nozzle_size"), line_width_0, line_width_x, inset_count, mesh.getSettingBoolean("remove_overlapping_walls_0_enabled"), mesh.getSettingBoolean("remove_overlapping_walls_x_enabled"));

            for(unsigned int partNr=0; partNr<layer->parts.size(); partNr++)
            {
                if (layer->parts[partNr].insets.size() > 0)
                {
//                     sendPolygons(Inset0Type, layer_nr, layer->parts[partNr].insets[0], line_width_0); // done after processing fuzzy skin
                    for(unsigned int inset=1; inset<layer->parts[partNr].insets.size(); inset++)
                        sendPolygons(InsetXType, layer_nr, layer->parts[partNr].insets[inset], line_width_x);
                }
            }
        }
        if (mesh.getSettingAsSurfaceMode("magic_mesh_surface_mode") != ESurfaceMode::NORMAL)
        {
            for (PolygonRef polyline : layer->openPolyLines)
            {
                Polygons segments;
                for (unsigned int point_idx = 1; point_idx < polyline.size(); point_idx++)
                {
                    PolygonRef segment = segments.newPoly();
                    segment.add(polyline[point_idx-1]);
                    segment.add(polyline[point_idx]);
                }
                sendPolygons(Inset0Type, layer_nr, segments, mesh.getSettingInMicrons("wall_line_width_0"));
            }
        }
    }
}

void FffPolygonGenerator::processWipeTower(SliceDataStorage& storage, unsigned int totalLayers)
{
    
    
    // TODO: move this code into its own function?
    { // compute storage.max_object_height_second_to_last_extruder, which is used to determine the highest point in the wipe tower
        
        int max_object_height_per_extruder[MAX_EXTRUDERS];
        { // compute max_object_height_per_extruder
            memset(max_object_height_per_extruder, -1, sizeof(max_object_height_per_extruder));
            for (SliceMeshStorage& mesh : storage.meshes)
            {
                max_object_height_per_extruder[mesh.settings->getSettingAsIndex("extruder_nr")] = 
                    std::max(   max_object_height_per_extruder[mesh.settings->getSettingAsIndex("extruder_nr")]
                            ,   mesh.layer_nr_max_filled_layer  ); 
            }
            int support_extruder_nr = getSettingAsIndex("support_extruder_nr");
            max_object_height_per_extruder[support_extruder_nr] = 
            std::max(   max_object_height_per_extruder[support_extruder_nr]
                    ,   storage.support.layer_nr_max_filled_layer  ); 
        }
        { // // compute max_object_height_second_to_last_extruder
            int extruder_max_object_height = 0;
            for (unsigned int extruder_nr = 1; extruder_nr < MAX_EXTRUDERS; extruder_nr++)
            {
                if (max_object_height_per_extruder[extruder_nr] > max_object_height_per_extruder[extruder_max_object_height])
                {
                    extruder_max_object_height = extruder_nr;
                }
            }
            int extruder_second_max_object_height = -1;
            for (int extruder_nr = 0; extruder_nr < MAX_EXTRUDERS; extruder_nr++)
            {
                if (extruder_nr == extruder_max_object_height) { continue; }
                if (max_object_height_per_extruder[extruder_nr] > max_object_height_per_extruder[extruder_second_max_object_height])
                {
                    extruder_second_max_object_height = extruder_nr;
                }
            }
            if (extruder_second_max_object_height < 0)
            {
                storage.max_object_height_second_to_last_extruder = -1;
            }
            else 
            {
                storage.max_object_height_second_to_last_extruder = max_object_height_per_extruder[extruder_second_max_object_height];
            }
        }
    }
       
        
    if (storage.max_object_height_second_to_last_extruder >= 0 && getSettingInMicrons("wipe_tower_distance") > 0 && getSettingInMicrons("wipe_tower_size") > 0)
    {
        PolygonRef p = storage.wipeTower.newPoly();
        int tower_size = getSettingInMicrons("wipe_tower_size");
        int tower_distance = getSettingInMicrons("wipe_tower_distance");
        p.add(Point(storage.model_min.x - tower_distance, storage.model_max.y + tower_distance));
        p.add(Point(storage.model_min.x - tower_distance, storage.model_max.y + tower_distance + tower_size));
        p.add(Point(storage.model_min.x - tower_distance - tower_size, storage.model_max.y + tower_distance + tower_size));
        p.add(Point(storage.model_min.x - tower_distance - tower_size, storage.model_max.y + tower_distance));

        storage.wipePoint = Point(storage.model_min.x - tower_distance - tower_size / 2, storage.model_max.y + tower_distance + tower_size / 2);
    }
}

void SlicerLayer::makePolygons(Mesh* mesh, bool keep_none_closed, bool extensive_stitching)
{
    Polygons openPolygonList;
    
    for(unsigned int startSegment=0; startSegment < segmentList.size(); startSegment++)
    {
        if (segmentList[startSegment].addedToPolygon)
            continue;
        
        Polygon poly;
        poly.add(segmentList[startSegment].start);
        
        unsigned int segmentIndex = startSegment;
        bool canClose;
        while(true)
        {
            canClose = false;
            segmentList[segmentIndex].addedToPolygon = true;
            Point p0 = segmentList[segmentIndex].end;
            poly.add(p0);
            int nextIndex = -1;
            const MeshFace& face = mesh->faces[segmentList[segmentIndex].faceIndex];
            for(unsigned int i=0;i<3;i++)
            {
                decltype(face_idx_to_segment_index.begin()) it;
                if (face.connected_face_index[i] > -1 && (it = face_idx_to_segment_index.find(face.connected_face_index[i])) != face_idx_to_segment_index.end())
                {
                    int index = (*it).second;
                    Point p1 = segmentList[index].start;
                    Point diff = p0 - p1;
                    if (shorterThen(diff, MM2INT(0.01)))
                    {
                        if (index == static_cast<int>(startSegment))
                            canClose = true;
                        if (segmentList[index].addedToPolygon)
                            continue;
                        nextIndex = index;
                    }
                }
            }
            if (nextIndex == -1)
                break;
            segmentIndex = nextIndex;
        }
        if (canClose)
            polygonList.add(poly);
        else
            openPolygonList.add(poly);
    }
    //Clear the segmentList to save memory, it is no longer needed after this point.
    segmentList.clear();

    //Connecting polygons that are not closed yet, as models are not always perfect manifold we need to join some stuff up to get proper polygons
    //First link up polygon ends that are within 2 microns.
    for(unsigned int i=0;i<openPolygonList.size();i++)
    {
        if (openPolygonList[i].size() < 1) continue;
        for(unsigned int j=0;j<openPolygonList.size();j++)
        {
            if (openPolygonList[j].size() < 1) continue;
            
            Point diff = openPolygonList[i][openPolygonList[i].size()-1] - openPolygonList[j][0];
            int64_t distSquared = vSize2(diff);

            if (distSquared < MM2INT(0.02) * MM2INT(0.02))
            {
                if (i == j)
                {
                    polygonList.add(openPolygonList[i]);
                    openPolygonList[i].clear();
                    break;
                }else{
                    for(unsigned int n=0; n<openPolygonList[j].size(); n++)
                        openPolygonList[i].add(openPolygonList[j][n]);

                    openPolygonList[j].clear();
                }
            }
        }
    }

    //Next link up all the missing ends, closing up the smallest gaps first. This is an inefficient implementation which can run in O(n*n*n) time.
    while(1)
    {
        int64_t bestScore = MM2INT(10.0) * MM2INT(10.0);
        unsigned int bestA = -1;
        unsigned int bestB = -1;
        bool reversed = false;
        for(unsigned int i=0;i<openPolygonList.size();i++)
        {
            if (openPolygonList[i].size() < 1) continue;
            for(unsigned int j=0;j<openPolygonList.size();j++)
            {
                if (openPolygonList[j].size() < 1) continue;
                
                Point diff = openPolygonList[i][openPolygonList[i].size()-1] - openPolygonList[j][0];
                int64_t distSquared = vSize2(diff);
                if (distSquared < bestScore)
                {
                    bestScore = distSquared;
//.........这里部分代码省略.........

void generateZigZagIninfill_noEndPieces(const Polygons& in_outline, Polygons& result, int extrusionWidth, int lineSpacing, double infillOverlap, double rotation)
{
    if (in_outline.size() == 0) return;
    Polygons outline = in_outline.offset(extrusionWidth * infillOverlap / 100 - extrusionWidth / 2);
    if (outline.size() == 0) return;
    
    PointMatrix matrix(rotation);
    
    outline.applyMatrix(matrix);
    
    auto addLine = [&](Point from, Point to)
    {            
        PolygonRef p = result.newPoly();
        p.add(matrix.unapply(from));
        p.add(matrix.unapply(to));
    };   
        
    AABB boundary(outline);
    
    int scanline_min_idx = boundary.min.X / lineSpacing;
    int lineCount = (boundary.max.X + (lineSpacing - 1)) / lineSpacing - scanline_min_idx;
    
    std::vector<std::vector<int64_t> > cutList; // mapping from scanline to all intersections with polygon segments
    
    for(int n=0; n<lineCount; n++)
        cutList.push_back(std::vector<int64_t>());
    for(unsigned int polyNr=0; polyNr < outline.size(); polyNr++)
    {
        std::vector<Point> firstBoundarySegment;
        std::vector<Point> boundarySegment;
        
        bool isFirstBoundarySegment = true;
        bool firstBoundarySegmentEndsInEven;
        
        bool isEvenScanSegment = false; 
        
        
        Point p0 = outline[polyNr][outline[polyNr].size()-1];
        for(unsigned int i=0; i < outline[polyNr].size(); i++)
        {
            Point p1 = outline[polyNr][i];
            int64_t xMin = p1.X, xMax = p0.X;
            if (xMin == xMax) {
                p0 = p1;
                continue; 
            }
            if (xMin > xMax) { xMin = p0.X; xMax = p1.X; }
            
            int scanline_idx0 = (p0.X + ((p0.X > 0)? -1 : -lineSpacing)) / lineSpacing; // -1 cause a linesegment on scanline x counts as belonging to scansegment x-1   ...
            int scanline_idx1 = (p1.X + ((p1.X > 0)? -1 : -lineSpacing)) / lineSpacing; // -linespacing because a line between scanline -n and -n-1 belongs to scansegment -n-1 (for n=positive natural number)
            int direction = 1;
            if (p0.X > p1.X) 
            { 
                direction = -1; 
                scanline_idx1 += 1; // only consider the scanlines in between the scansegments
            } else scanline_idx0 += 1; // only consider the scanlines in between the scansegments
            
            
            if (isFirstBoundarySegment) firstBoundarySegment.push_back(p0);
            else boundarySegment.push_back(p0);
            for(int scanline_idx = scanline_idx0; scanline_idx != scanline_idx1+direction; scanline_idx+=direction)
            {
                int x = scanline_idx * lineSpacing;
                int y = p1.Y + (p0.Y - p1.Y) * (x - p1.X) / (p0.X - p1.X);
                cutList[scanline_idx - scanline_min_idx].push_back(y);
                
                
                bool last_isEvenScanSegment = isEvenScanSegment;
                if (scanline_idx % 2 == 0) isEvenScanSegment = true;
                else isEvenScanSegment = false;
                
                if (!isFirstBoundarySegment)
                {
                    if (last_isEvenScanSegment && !isEvenScanSegment)
                    { // add whole boundarySegment (including the just obtained point)
                        for (unsigned int p = 1; p < boundarySegment.size(); p++)
                        {
                            addLine(boundarySegment[p-1], boundarySegment[p]);
                        }
                        addLine(boundarySegment[boundarySegment.size()-1], Point(x,y));
                        boundarySegment.clear();
                    } 
                    else if (isEvenScanSegment) // we are either in an end piece or an uneven boundary segment
                    {
                        boundarySegment.clear();
                        boundarySegment.emplace_back(x,y);
                    } else
                        boundarySegment.clear();
                        
                }
                
                if (isFirstBoundarySegment) 
                {
                    firstBoundarySegment.emplace_back(x,y);
                    firstBoundarySegmentEndsInEven = isEvenScanSegment;
                    isFirstBoundarySegment = false;
                    boundarySegment.emplace_back(x,y);
                }
                
            }
//.........这里部分代码省略.........

/*!
 * adapted from generateLineInfill(.)
 * 
 * generate lines within the area of [in_outline], at regular intervals of [lineSpacing]
 * idea:
 * intersect a regular grid of 'scanlines' with the area inside [in_outline]
 * sigzag:
 * include pieces of boundary, connecting the lines, forming an accordion like zigzag instead of separate lines    |_|^|_|
 * 
 * we call the areas between two consecutive scanlines a 'scansegment'
 * 
 * algorithm:
 * 1. for each line segment of each polygon:
 *      store the intersections of that line segment with all scanlines in a mapping (vector of vectors) from scanline to intersections
 *      (zigzag): add boundary segments to result
 * 2. for each scanline:
 *      sort the associated intersections 
 *      and connect them using the even-odd rule
 * 
 * zigzag algorithm:
 * while walking around (each) polygon (1.)
 *  if polygon intersects with even scanline
 *      start boundary segment (add each following segment to the [result])
 *  when polygon intersects with a scanline again
 *      stop boundary segment (stop adding segments to the [result])
 *      if polygon intersects with even scanline again (instead of odd)
 *          dont add the last line segment to the boundary (unless [connect_zigzags])
 * 
 * 
 *     <--
 *     ___
 *    |   |   |
 *    |   |   |
 *    |   |___|
 *         -->
 * 
 *        ^ = even scanline
 * 
 * start boundary from even scanline! :D
 * 
 * 
 *          _____
 *   |     |     | ,
 *   |     |     |  |
 *   |_____|     |__/
 * 
 *   ^     ^     ^    scanlines
 *                 ^  disconnected end piece
 */
void generateZigZagIninfill_endPieces(const Polygons& in_outline, Polygons& result, int extrusionWidth, int lineSpacing, double infillOverlap, double rotation, bool connect_zigzags)
{
//     if (in_outline.size() == 0) return;
//     Polygons outline = in_outline.offset(extrusionWidth * infillOverlap / 100 - extrusionWidth / 2);
    Polygons empty;
    Polygons outline = in_outline.difference(empty); // copy
    if (outline.size() == 0) return;
    
    PointMatrix matrix(rotation);
    
    outline.applyMatrix(matrix);
    
    auto addLine = [&](Point from, Point to)
    {            
        PolygonRef p = result.newPoly();
        p.add(matrix.unapply(from));
        p.add(matrix.unapply(to));
    };   
        
    AABB boundary(outline);
    
    int scanline_min_idx = boundary.min.X / lineSpacing;
    int lineCount = (boundary.max.X + (lineSpacing - 1)) / lineSpacing - scanline_min_idx;
    
    std::vector<std::vector<int64_t> > cutList; // mapping from scanline to all intersections with polygon segments
    
    for(int n=0; n<lineCount; n++)
        cutList.push_back(std::vector<int64_t>());
    for(unsigned int polyNr=0; polyNr < outline.size(); polyNr++)
    {
        std::vector<Point> firstBoundarySegment;
        std::vector<Point> unevenBoundarySegment; // stored cause for connected_zigzags a boundary segment which ends in an uneven scanline needs to be included
        
        bool isFirstBoundarySegment = true;
        bool firstBoundarySegmentEndsInEven;
        
        bool isEvenScanSegment = false; 
        
        
        Point p0 = outline[polyNr][outline[polyNr].size()-1];
        Point lastPoint = p0;
        for(unsigned int i=0; i < outline[polyNr].size(); i++)
        {
            Point p1 = outline[polyNr][i];
            int64_t xMin = p1.X, xMax = p0.X;
            if (xMin == xMax) {
                lastPoint = p1;
                p0 = p1;
                continue; 
            }
            if (xMin > xMax) { xMin = p0.X; xMax = p1.X; }
//.........这里部分代码省略.........