C++ Polygons::begin方法代码示例

ClipperLib::Paths Slic3rMultiPoints_to_ClipperPaths(const Polygons &input)
{
    ClipperLib::Paths retval;
    for (Polygons::const_iterator it = input.begin(); it != input.end(); ++it)
        retval.emplace_back(Slic3rMultiPoint_to_ClipperPath(*it));
    return retval;
}

Slic3r::Polygons
union_(const Slic3r::ExPolygons &subject1, const Slic3r::ExPolygons &subject2, bool safety_offset)
{
    Polygons pp;
    for (Slic3r::ExPolygons::const_iterator it = subject1.begin(); it != subject1.end(); ++it) {
        Polygons spp = *it;
        pp.insert(pp.end(), spp.begin(), spp.end());
    }
    for (Slic3r::ExPolygons::const_iterator it = subject2.begin(); it != subject2.end(); ++it) {
        Polygons spp = *it;
        pp.insert(pp.end(), spp.begin(), spp.end());
    }
    Polygons retval;
    union_(pp, &retval, safety_offset);
    return retval;
}

void
Polygon::simplify(double tolerance, Polygons &polygons) const
{
    Polygons pp = this->simplify(tolerance);
    polygons.reserve(polygons.size() + pp.size());
    polygons.insert(polygons.end(), pp.begin(), pp.end());
}

std::string
SLAPrint::_SVG_path_d(const ExPolygon &expolygon) const
{
    std::string pd;
    const Polygons pp = expolygon;
    for (Polygons::const_iterator mp = pp.begin(); mp != pp.end(); ++mp) 
        pd += this->_SVG_path_d(*mp) + " ";
    return pd;
}

ExPolygonCollection::operator Points() const
{
    Points points;
    Polygons pp = *this;
    for (Polygons::const_iterator poly = pp.begin(); poly != pp.end(); ++poly) {
        for (Points::const_iterator point = poly->points.begin(); point != poly->points.end(); ++point)
            points.push_back(*point);
    }
    return points;
}

void
SurfaceCollection::filter_by_type(SurfaceType type, Polygons* polygons)
{
    for (Surfaces::iterator surface = this->surfaces.begin(); surface != this->surfaces.end(); ++surface) {
        if (surface->surface_type == type) {
            Polygons pp = surface->expolygon;
            polygons->insert(polygons->end(), pp.begin(), pp.end());
        }
    }
}

Slic3r::ExPolygons
union_ex(const Slic3r::Surfaces &subject, bool safety_offset)
{
    Polygons pp;
    for (Slic3r::Surfaces::const_iterator s = subject.begin(); s != subject.end(); ++s) {
        Polygons spp = *s;
        pp.insert(pp.end(), spp.begin(), spp.end());
    }
    return union_ex(pp, safety_offset);
}

void
SVG::draw(const ExPolygon &expolygon, std::string fill)
{
    this->fill = fill;
    
    std::string d;
    Polygons pp = expolygon;
    for (Polygons::const_iterator p = pp.begin(); p != pp.end(); ++p) {
        d += this->get_path_d(*p, true) + " ";
    }
    this->path(d, true);
}

inline Polylines to_polylines(const Polygons &polys)
{
    Polylines polylines;
    polylines.assign(polys.size(), Polyline());
    size_t idx = 0;
    for (Polygons::const_iterator it = polys.begin(); it != polys.end(); ++ it) {
        Polyline &pl = polylines[idx ++];
        pl.points = it->points;
        pl.points.push_back(it->points.front());
    }
    assert(idx == polylines.size());
    return polylines;
}

Polylines
_clipper_pl(ClipperLib::ClipType clipType, const Polygons &subject, 
    const Polygons &clip, bool safety_offset_)
{
    // transform input polygons into polylines
    Polylines polylines;
    polylines.reserve(subject.size());
    for (Polygons::const_iterator polygon = subject.begin(); polygon != subject.end(); ++polygon)
        polylines.push_back(*polygon);  // implicit call to split_at_first_point()
    
    // perform clipping
    Polylines retval = _clipper_pl(clipType, polylines, clip, safety_offset_);
    
    /* If the split_at_first_point() call above happens to split the polygon inside the clipping area
       we would get two consecutive polylines instead of a single one, so we go through them in order
       to recombine continuous polylines. */
    for (size_t i = 0; i < retval.size(); ++i) {
        for (size_t j = i+1; j < retval.size(); ++j) {
            if (retval[i].points.back().coincides_with(retval[j].points.front())) {
                /* If last point of i coincides with first point of j,
                   append points of j to i and delete j */
                retval[i].points.insert(retval[i].points.end(), retval[j].points.begin()+1, retval[j].points.end());
                retval.erase(retval.begin() + j);
                --j;
            } else if (retval[i].points.front().coincides_with(retval[j].points.back())) {
                /* If first point of i coincides with last point of j,
                   prepend points of j to i and delete j */
                retval[i].points.insert(retval[i].points.begin(), retval[j].points.begin(), retval[j].points.end()-1);
                retval.erase(retval.begin() + j);
                --j;
            } else if (retval[i].points.front().coincides_with(retval[j].points.front())) {
                /* Since Clipper does not preserve orientation of polylines, 
                   also check the case when first point of i coincides with first point of j. */
                retval[j].reverse();
                retval[i].points.insert(retval[i].points.begin(), retval[j].points.begin(), retval[j].points.end()-1);
                retval.erase(retval.begin() + j);
                --j;
            } else if (retval[i].points.back().coincides_with(retval[j].points.back())) {
                /* Since Clipper does not preserve orientation of polylines, 
                   also check the case when last point of i coincides with last point of j. */
                retval[j].reverse();
                retval[i].points.insert(retval[i].points.end(), retval[j].points.begin()+1, retval[j].points.end());
                retval.erase(retval.begin() + j);
                --j;
            }
        }
    }
    return retval;
}

void
BridgeDetector::unsupported_edges(double angle, Polylines* unsupported) const
{
    // get bridge edges (both contour and holes)
    Polylines bridge_edges;
    {
        Polygons pp = this->expolygon;
        bridge_edges.insert(bridge_edges.end(), pp.begin(), pp.end());  // this uses split_at_first_point()
    }

    // get unsupported edges
    Polygons grown_lower;
    offset(this->lower_slices, &grown_lower, +this->extrusion_width);
    Polylines _unsupported;
    diff(bridge_edges, grown_lower, &_unsupported);

    /*  Split into individual segments and filter out edges parallel to the bridging angle
        TODO: angle tolerance should probably be based on segment length and flow width,
        so that we build supports whenever there's a chance that at least one or two bridge
        extrusions would be anchored within such length (i.e. a slightly non-parallel bridging
        direction might still benefit from anchors if long enough) */
    double angle_tolerance = PI / 180.0 * 5.0;
    for (Polylines::const_iterator polyline = _unsupported.begin(); polyline != _unsupported.end(); ++polyline) {
        Lines lines = polyline->lines();
        for (Lines::const_iterator line = lines.begin(); line != lines.end(); ++line) {
            if (!xd::Geometry::directions_parallel(line->direction(), angle))
                unsupported->push_back(*line);
        }
    }

    /*
    if (0) {
        require "Slic3r/SVG.pm";
        Slic3r::SVG::output(
            "unsupported_" . rad2deg($angle) . ".svg",
            expolygons          => [$self->expolygon],
            green_expolygons    => $self->_anchors,
            red_expolygons      => union_ex($grown_lower),
            no_arrows           => 1,
            polylines           => \@bridge_edges,
            red_polylines       => $unsupported,
        );
    }
    */
}

std::string
GCode::extrude(ExtrusionLoop loop, std::string description, double speed)
{
    // get a copy; don't modify the orientation of the original loop object otherwise
    // next copies (if any) would not detect the correct orientation
    
    // extrude all loops ccw
    bool was_clockwise = loop.make_counter_clockwise();
    
    SeamPosition seam_position = this->config.seam_position;
    if (loop.role == elrSkirt) seam_position = spNearest;
    
    // find the point of the loop that is closest to the current extruder position
    // or randomize if requested
    Point last_pos = this->last_pos();
    if (this->config.spiral_vase) {
        loop.split_at(last_pos);
    } else if (seam_position == spNearest || seam_position == spAligned) {
        const Polygon polygon = loop.polygon();
        
        // simplify polygon in order to skip false positives in concave/convex detection
        // (loop is always ccw as polygon.simplify() only works on ccw polygons)
        Polygons simplified = polygon.simplify(scale_(EXTRUDER_CONFIG(nozzle_diameter))/2);
        
        // restore original winding order so that concave and convex detection always happens
        // on the right/outer side of the polygon
        if (was_clockwise) {
            for (Polygons::iterator p = simplified.begin(); p != simplified.end(); ++p)
                p->reverse();
        }
        
        // concave vertices have priority
        Points candidates;
        for (Polygons::const_iterator p = simplified.begin(); p != simplified.end(); ++p) {
            Points concave = p->concave_points(PI*4/3);
            candidates.insert(candidates.end(), concave.begin(), concave.end());
        }
        
        // if no concave points were found, look for convex vertices
        if (candidates.empty()) {
            for (Polygons::const_iterator p = simplified.begin(); p != simplified.end(); ++p) {
                Points convex = p->convex_points(PI*2/3);
                candidates.insert(candidates.end(), convex.begin(), convex.end());
            }
        }
        
        // retrieve the last start position for this object
        if (this->layer != NULL && this->_seam_position.count(this->layer->object()) > 0) {
            last_pos = this->_seam_position[this->layer->object()];
        }
        
        Point point;
        if (seam_position == spNearest) {
            if (candidates.empty()) candidates = polygon.points;
            last_pos.nearest_point(candidates, &point);
            
            // On 32-bit Linux, Clipper will change some point coordinates by 1 unit
            // while performing simplify_polygons(), thus split_at_vertex() won't 
            // find them anymore.
            if (!loop.split_at_vertex(point)) loop.split_at(point);
        } else if (!candidates.empty()) {
            Points non_overhang;
            for (Points::const_iterator p = candidates.begin(); p != candidates.end(); ++p) {
                if (!loop.has_overhang_point(*p))
                    non_overhang.push_back(*p);
            }
            
            if (!non_overhang.empty())
                candidates = non_overhang;
            
            last_pos.nearest_point(candidates, &point);
            if (!loop.split_at_vertex(point)) loop.split_at(point);  // see note above
        } else {
            point = last_pos.projection_onto(polygon);
            loop.split_at(point);
        }
        if (this->layer != NULL)
            this->_seam_position[this->layer->object()] = point;
    } else if (seam_position == spRandom) {
        if (loop.role == elrContourInternalPerimeter) {
            Polygon polygon = loop.polygon();
            Point centroid = polygon.centroid();
            last_pos = Point(polygon.bounding_box().max.x, centroid.y);
            last_pos.rotate(fmod((float)rand()/16.0, 2.0*PI), centroid);
        }
        loop.split_at(last_pos);
    }
    
    // clip the path to avoid the extruder to get exactly on the first point of the loop;
    // if polyline was shorter than the clipping distance we'd get a null polyline, so
    // we discard it in that case
    double clip_length = this->enable_loop_clipping
        ? scale_(EXTRUDER_CONFIG(nozzle_diameter)) * LOOP_CLIPPING_LENGTH_OVER_NOZZLE_DIAMETER
        : 0;
    
    // get paths
    ExtrusionPaths paths;
    loop.clip_end(clip_length, &paths);
    if (paths.empty()) return "";
    
//.........这里部分代码省略.........

MotionPlannerGraph*
MotionPlanner::init_graph(int island_idx)
{
    if (this->graphs[island_idx + 1] == NULL) {
        Polygons pp;
        if (island_idx == -1) {
            pp = this->outer;
        } else {
            pp = this->inner[island_idx];
        }
        
        MotionPlannerGraph* graph = this->graphs[island_idx + 1] = new MotionPlannerGraph();
        
        // add polygon boundaries as edges
        size_t node_idx = 0;
        Lines lines;
        for (Polygons::const_iterator polygon = pp.begin(); polygon != pp.end(); ++polygon) {
            graph->nodes.push_back(polygon->points.back());
            node_idx++;
            for (Points::const_iterator p = polygon->points.begin(); p != polygon->points.end(); ++p) {
                graph->nodes.push_back(*p);
                double dist = graph->nodes[node_idx-1].distance_to(*p);
                graph->add_edge(node_idx-1, node_idx, dist);
                graph->add_edge(node_idx, node_idx-1, dist);
                node_idx++;
            }
            polygon->lines(&lines);
        }
        
        // add Voronoi edges as internal edges
        {
            typedef voronoi_diagram<double> VD;
            typedef std::map<const VD::vertex_type*,size_t> t_vd_vertices;
            VD vd;
            t_vd_vertices vd_vertices;
            
            boost::polygon::construct_voronoi(lines.begin(), lines.end(), &vd);
            for (VD::const_edge_iterator edge = vd.edges().begin(); edge != vd.edges().end(); ++edge) {
                if (edge->is_infinite()) continue;
                
                const VD::vertex_type* v0 = edge->vertex0();
                const VD::vertex_type* v1 = edge->vertex1();
                Point p0 = Point(v0->x(), v0->y());
                Point p1 = Point(v1->x(), v1->y());
                // contains() should probably be faster than contains(),
                // and should it fail on any boundary points it's not a big problem
                if (island_idx == -1) {
                    if (!this->outer.contains(p0) || !this->outer.contains(p1)) continue;
                } else {
                    if (!this->inner[island_idx].contains(p0) || !this->inner[island_idx].contains(p1)) continue;
                }
                
                t_vd_vertices::const_iterator i_v0 = vd_vertices.find(v0);
                size_t v0_idx;
                if (i_v0 == vd_vertices.end()) {
                    graph->nodes.push_back(p0);
                    v0_idx = node_idx;
                    vd_vertices[v0] = node_idx;
                    node_idx++;
                } else {
                    v0_idx = i_v0->second;
                }
                
                t_vd_vertices::const_iterator i_v1 = vd_vertices.find(v1);
                size_t v1_idx;
                if (i_v1 == vd_vertices.end()) {
                    graph->nodes.push_back(p1);
                    v1_idx = node_idx;
                    vd_vertices[v1] = node_idx;
                    node_idx++;
                } else {
                    v1_idx = i_v1->second;
                }
                
                double dist = graph->nodes[v0_idx].distance_to(graph->nodes[v1_idx]);
                graph->add_edge(v0_idx, v1_idx, dist);
            }
        }
        
        return graph;
    }
    return this->graphs[island_idx + 1];
}

inline void polygons_rotate(Polygons &polys, double angle)
{
    for (Polygons::iterator p = polys.begin(); p != polys.end(); ++p)
        p->rotate(angle);
}

void
PerimeterGenerator::process()
{
    // other perimeters
    this->_mm3_per_mm           = this->perimeter_flow.mm3_per_mm();
    coord_t pwidth              = this->perimeter_flow.scaled_width();
    coord_t pspacing            = this->perimeter_flow.scaled_spacing();
    
    // external perimeters
    this->_ext_mm3_per_mm       = this->ext_perimeter_flow.mm3_per_mm();
    coord_t ext_pwidth          = this->ext_perimeter_flow.scaled_width();
    coord_t ext_pspacing        = this->ext_perimeter_flow.scaled_spacing();
    coord_t ext_pspacing2       = this->ext_perimeter_flow.scaled_spacing(this->perimeter_flow);
    
    // overhang perimeters
    this->_mm3_per_mm_overhang  = this->overhang_flow.mm3_per_mm();
    
    // solid infill
    coord_t ispacing            = this->solid_infill_flow.scaled_spacing();
    coord_t gap_area_threshold  = pwidth * pwidth;
    
    // Calculate the minimum required spacing between two adjacent traces.
    // This should be equal to the nominal flow spacing but we experiment
    // with some tolerance in order to avoid triggering medial axis when
    // some squishing might work. Loops are still spaced by the entire
    // flow spacing; this only applies to collapsing parts.
    // For ext_min_spacing we use the ext_pspacing calculated for two adjacent
    // external loops (which is the correct way) instead of using ext_pspacing2
    // which is the spacing between external and internal, which is not correct
    // and would make the collapsing (thus the details resolution) dependent on 
    // internal flow which is unrelated.
    coord_t min_spacing         = pspacing      * (1 - INSET_OVERLAP_TOLERANCE);
    coord_t ext_min_spacing     = ext_pspacing  * (1 - INSET_OVERLAP_TOLERANCE);
    
    // prepare grown lower layer slices for overhang detection
    if (this->lower_slices != NULL && this->config->overhangs) {
        // We consider overhang any part where the entire nozzle diameter is not supported by the
        // lower layer, so we take lower slices and offset them by half the nozzle diameter used 
        // in the current layer
        double nozzle_diameter = this->print_config->nozzle_diameter.get_at(this->config->perimeter_extruder-1);
        
        this->_lower_slices_p = offset(*this->lower_slices, scale_(+nozzle_diameter/2));
    }
    
    // we need to process each island separately because we might have different
    // extra perimeters for each one
    for (Surfaces::const_iterator surface = this->slices->surfaces.begin();
        surface != this->slices->surfaces.end(); ++surface) {
        // detect how many perimeters must be generated for this island
        signed short loop_number = this->config->perimeters + surface->extra_perimeters;
        loop_number--;  // 0-indexed loops
        
        Polygons gaps;
        
        Polygons last = surface->expolygon.simplify_p(SCALED_RESOLUTION);
        if (loop_number >= 0) {  // no loops = -1
            
            std::vector<PerimeterGeneratorLoops> contours(loop_number+1);    // depth => loops
            std::vector<PerimeterGeneratorLoops> holes(loop_number+1);       // depth => loops
            Polylines thin_walls;
            
            // we loop one time more than needed in order to find gaps after the last perimeter was applied
            for (signed short i = 0; i <= loop_number+1; ++i) {  // outer loop is 0
                Polygons offsets;
                if (i == 0) {
                    // the minimum thickness of a single loop is:
                    // ext_width/2 + ext_spacing/2 + spacing/2 + width/2
                    if (this->config->thin_walls) {
                        offsets = offset2(
                            last,
                            -(ext_pwidth/2 + ext_min_spacing/2 - 1),
                            +(ext_min_spacing/2 - 1)
                        );
                    } else {
                        offsets = offset(last, -ext_pwidth/2);
                    }
                    
                    // look for thin walls
                    if (this->config->thin_walls) {
                        Polygons diffpp = diff(
                            last,
                            offset(offsets, +ext_pwidth/2),
                            true  // medial axis requires non-overlapping geometry
                        );
                        
                        // the following offset2 ensures almost nothing in @thin_walls is narrower than $min_width
                        // (actually, something larger than that still may exist due to mitering or other causes)
                        coord_t min_width = ext_pwidth / 2;
                        ExPolygons expp = offset2_ex(diffpp, -min_width/2, +min_width/2);
                        
                        // the maximum thickness of our thin wall area is equal to the minimum thickness of a single loop
                        Polylines pp;
                        for (ExPolygons::const_iterator ex = expp.begin(); ex != expp.end(); ++ex)
                            ex->medial_axis(ext_pwidth + ext_pspacing2, min_width, &pp);
                        
                        double threshold = ext_pwidth * 2;
                        for (Polylines::const_iterator p = pp.begin(); p != pp.end(); ++p) {
                            if (p->length() > threshold) {
                                thin_walls.push_back(*p);
                            }
//.........这里部分代码省略.........