C++ Polygons::newPoly方法代码示例

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 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::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 Weaver::chainify_polygons(Polygons& parts1, Point start_close_to, Polygons& result, bool include_last)
{
    for (unsigned int prt = 0 ; prt < parts1.size(); prt++)
    {
        const PolygonRef upperPart = parts1[prt];
        
        ClosestPolygonPoint closestInPoly = PolygonUtils::findClosest(start_close_to, upperPart);

        
        PolygonRef part_top = result.newPoly();
        
        GivenDistPoint next_upper;
        bool found = true;
        int idx = 0;
        
        for (Point upper_point = upperPart[closestInPoly.point_idx]; found; upper_point = next_upper.location)
        {
            found = PolygonUtils::getNextPointWithDistance(upper_point, nozzle_top_diameter, upperPart, idx, closestInPoly.point_idx, next_upper);

            
            if (!found) 
            {
                break;
            }
            
            part_top.add(upper_point);
            
            idx = next_upper.pos;
        }
        if (part_top.size() > 0)
            start_close_to = part_top.back();
        else
            result.remove(result.size()-1);
    }
}

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 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 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 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.........

  void generateTroctInfill(const Polygons& in_outline, Polygons& result, int extrusionWidth, int lineSpacing, int infillOverlap, double rotation, int posZ)
  {
    Polygons outline = in_outline.offset(extrusionWidth * infillOverlap / 100);
    PointMatrix matrix(rotation);
    outline.applyMatrix(matrix);
    AABB boundary(outline);

    // ignore infill for areas smaller than line spacing
    if((abs(boundary.min.X - boundary.max.X) + abs(boundary.min.Y - boundary.max.Y)) < lineSpacing){
      return;
    }

    // fix to normalise against diagonal infill
    lineSpacing = lineSpacing * 2;

    uint64_t Zscale = SQRT2MUL(lineSpacing);

    int offset = abs(posZ % (Zscale) - (Zscale/2)) - (Zscale/4);
    boundary.min.X = ((boundary.min.X / lineSpacing) - 1) * lineSpacing;
    boundary.min.Y = ((boundary.min.Y / lineSpacing) - 1) * lineSpacing;

    unsigned int lineCountX = (boundary.max.X - boundary.min.X + (lineSpacing - 1)) / lineSpacing;
    unsigned int lineCountY = (boundary.max.Y - boundary.min.Y + (lineSpacing - 1)) / lineSpacing;
    int rtMod = int(rotation / 90) % 2;
    // with an odd number of lines, sides need to be swapped around
    if(rtMod == 1){
      rtMod = (lineCountX + int(rotation / 90)) % 2;
    }

    // draw non-horizontal walls of octohedrons
    Polygons po;
    PolygonRef p = po.newPoly();
    for(unsigned int ly=0; ly < lineCountY;){
      for(size_t it = 0; it < 2; ly++, it++){
        int side = (2*((ly + it + rtMod) % 2) - 1);
        int y = (ly * lineSpacing) + boundary.min.Y + lineSpacing / 2 - (offset/2 * side);
        int x = boundary.min.X-(offset/2);
        if(it == 1){
          x = (lineCountX * (lineSpacing)) + boundary.min.X + lineSpacing / 2 - (offset/2);
        }
        p.add(Point(x,y));
        for(unsigned int lx=0; lx < lineCountX; lx++){
          if(it == 1){
            side = (2*((lx + ly + it + rtMod + lineCountX) % 2) - 1);
            y = (ly * lineSpacing) + boundary.min.Y + lineSpacing / 2 + (offset/2 * side);
            x = ((lineCountX - lx - 1) * lineSpacing) + boundary.min.X + lineSpacing / 2;
            p.add(Point(x+lineSpacing-abs(offset/2), y));
            p.add(Point(x+abs(offset/2), y));
          } else {
            side = (2*((lx + ly + it + rtMod) % 2) - 1);
            y = (ly * lineSpacing) + boundary.min.Y + lineSpacing / 2 + (offset/2 * side);
            x = (lx * lineSpacing) + boundary.min.X + lineSpacing / 2;
            p.add(Point(x+abs(offset/2), y));
            p.add(Point(x+lineSpacing-abs(offset/2), y));
          }
        }
        x = (lineCountX * lineSpacing) + boundary.min.X + lineSpacing / 2 - (offset/2);
        if(it == 1){
          x = boundary.min.X-(offset/2);
        }
        y = (ly * lineSpacing) + boundary.min.Y + lineSpacing / 2 - (offset/2 * side);
        p.add(Point(x,y));
      }
    }
    // Generate tops / bottoms of octohedrons
    if(abs((abs(offset) - Zscale/4)) < (extrusionWidth/2)){
      uint64_t startLine = (offset < 0) ? 0 : 1;
      uint64_t coverWidth = OCTSLEN(lineSpacing);
      vector<Point> points;
      for(size_t xi = 0; xi < (lineCountX+1); xi++){
        for(size_t yi = 0; yi < (lineCountY); yi += 2){
          points.push_back(Point(boundary.min.X + OCTDLEN(lineSpacing)
                                 + (xi - startLine + rtMod) * lineSpacing,
                                 boundary.min.Y + OCTDLEN(lineSpacing)
                                 + (yi + (xi%2)) * lineSpacing
                                 + extrusionWidth/2));
        }
      }
      uint64_t order = 0;
      for(Point pp : points){
        PolygonRef p = po.newPoly();
        for(size_t yi = 0; yi <= coverWidth; yi += extrusionWidth) {
          if(order == 0){
            p.add(Point(pp.X, pp.Y + yi));
            p.add(Point(pp.X + coverWidth + extrusionWidth, pp.Y + yi));
          } else {
            p.add(Point(pp.X + coverWidth + extrusionWidth, pp.Y + yi));
            p.add(Point(pp.X, pp.Y + yi));
          }
          order = (order + 1) % 2;
        }
      }
    }
    // intersect with outline polygon(s)
    Polygons pi = po.intersection(outline);
    // Hack to add intersection to result. There doesn't seem
    // to be a direct way to do this
    for(unsigned int polyNr=0; polyNr < pi.size(); polyNr++) {
      PolygonRef p = result.newPoly(); //  = result.newPoly()
      for(unsigned int i=0; i < pi[polyNr].size(); i++) {
//.........这里部分代码省略.........