C++ ExPolygons::begin方法代码示例

MotionPlanner::MotionPlanner(const ExPolygons &islands)
    : initialized(false)
{
    ExPolygons expp;
    for (ExPolygons::const_iterator island = islands.begin(); island != islands.end(); ++island)
        island->simplify(SCALED_EPSILON, &expp);
    
    for (ExPolygons::const_iterator island = expp.begin(); island != expp.end(); ++island)
        this->islands.push_back(MotionPlannerEnv(*island));
}

inline bool expolygons_contain(ExPolygons &expolys, const Point &pt)
{
    for (ExPolygons::iterator p = expolys.begin(); p != expolys.end(); ++p)
        if (p->contains(pt))
            return true;
    return false;
}

// Count a nuber of polygons stored inside the vector of expolygons.
// Useful for allocating space for polygons when converting expolygons to polygons.
inline size_t number_polygons(const ExPolygons &expolys)
{
    size_t n_polygons = 0;
    for (ExPolygons::const_iterator it = expolys.begin(); it != expolys.end(); ++ it)
        n_polygons += it->holes.size() + 1;
    return n_polygons;
}

inline void polygons_append(Polygons &dst, const ExPolygons &src) 
{ 
    dst.reserve(dst.size() + number_polygons(src));
    for (ExPolygons::const_iterator it = src.begin(); it != src.end(); ++ it) {
        dst.push_back(it->contour);
        dst.insert(dst.end(), it->holes.begin(), it->holes.end());
    }
}

inline Polygons to_polygons(const ExPolygons &src)
{
    Polygons polygons;
    polygons.reserve(number_polygons(src));
    for (ExPolygons::const_iterator it = src.begin(); it != src.end(); ++it) {
        polygons.push_back(it->contour);
        polygons.insert(polygons.end(), it->holes.begin(), it->holes.end());
    }
    return polygons;
}

void
LayerRegion::merge_slices()
{
    // without safety offset, artifacts are generated (GH #2494)
    ExPolygons expp = union_ex((Polygons)this->slices, true);
    this->slices.surfaces.clear();
    this->slices.surfaces.reserve(expp.size());
    
    for (ExPolygons::const_iterator expoly = expp.begin(); expoly != expp.end(); ++expoly)
        this->slices.surfaces.push_back(Surface(stInternal, *expoly));
}

inline Lines to_lines(const ExPolygons &src) 
{
    size_t n_lines = 0;
    for (ExPolygons::const_iterator it_expoly = src.begin(); it_expoly != src.end(); ++ it_expoly) {
        n_lines += it_expoly->contour.points.size();
        for (size_t i = 0; i < it_expoly->holes.size(); ++ i)
            n_lines += it_expoly->holes[i].points.size();
    }
    Lines lines;
    lines.reserve(n_lines);
    for (ExPolygons::const_iterator it_expoly = src.begin(); it_expoly != src.end(); ++ it_expoly) {
        for (size_t i = 0; i <= it_expoly->holes.size(); ++ i) {
            const Points &points = ((i == 0) ? it_expoly->contour : it_expoly->holes[i - 1]).points;
            for (Points::const_iterator it = points.begin(); it != points.end()-1; ++it)
                lines.push_back(Line(*it, *(it + 1)));
            lines.push_back(Line(points.back(), points.front()));
        }
    }
    return lines;
}

void
SLAPrint::_infill_layer(size_t i, const Fill* _fill)
{
    Layer &layer = this->layers[i];
    
    const float shell_thickness = this->config.get_abs_value("perimeter_extrusion_width", this->config.layer_height.value);
    
    // In order to detect what regions of this layer need to be solid,
    // perform an intersection with layers within the requested shell thickness.
    Polygons internal = layer.slices;
    for (size_t j = 0; j < this->layers.size(); ++j) {
        const Layer &other = this->layers[j];
        if (abs(other.print_z - layer.print_z) > shell_thickness) continue;
    
        if (j == 0 || j == this->layers.size()-1) {
            internal.clear();
            break;
        } else if (i != j) {
            internal = intersection(internal, other.slices);
            if (internal.empty()) break;
        }
    }
    
    // If we have no internal infill, just print the whole layer as a solid slice.
    if (internal.empty()) return;
    layer.solid = false;
    
    const Polygons infill = offset(layer.slices, -scale_(shell_thickness));
    
    // Generate solid infill
    layer.solid_infill << diff_ex(infill, internal, true);
    
    // Generate internal infill
    {
        std::auto_ptr<Fill> fill(_fill->clone());
        fill->layer_id = i;
        fill->z        = layer.print_z;
        
        ExtrusionPath templ(erInternalInfill);
        templ.width = fill->spacing;
        const ExPolygons internal_ex = intersection_ex(infill, internal);
        for (ExPolygons::const_iterator it = internal_ex.begin(); it != internal_ex.end(); ++it) {
            Polylines polylines = fill->fill_surface(Surface(stInternal, *it));
            layer.infill.append(polylines, templ);
        }
    }
    
    // Generate perimeter(s).
    layer.perimeters << diff_ex(
        layer.slices,
        offset(layer.slices, -scale_(shell_thickness))
    );
}

ExtrusionEntityCollection
PerimeterGenerator::_fill_gaps(double min, double max, double w,
    const Polygons &gaps) const
{
    ExtrusionEntityCollection coll;
    
    min *= (1 - INSET_OVERLAP_TOLERANCE);
    
    ExPolygons curr = diff_ex(
        offset2(gaps, -min/2, +min/2),
        offset2(gaps, -max/2, +max/2),
        true
    );
    
    Polylines polylines;
    for (ExPolygons::const_iterator ex = curr.begin(); ex != curr.end(); ++ex)
        ex->medial_axis(max, min/2, &polylines);
    if (polylines.empty())
        return coll;
    
    #ifdef SLIC3R_DEBUG
    if (!curr.empty())
        printf("  %zu gaps filled with extrusion width = %f\n", curr.size(), w);
    #endif
    
    //my $flow = $layerm->flow(FLOW_ROLE_SOLID_INFILL, 0, $w);
    Flow flow(
        w, this->layer_height, this->solid_infill_flow.nozzle_diameter
    );
    
    double mm3_per_mm = flow.mm3_per_mm();
    
    for (Polylines::const_iterator p = polylines.begin(); p != polylines.end(); ++p) {
        ExtrusionPath path(erGapFill);
        path.polyline   = *p;
        path.mm3_per_mm = mm3_per_mm;
        path.width      = flow.width;
        path.height     = this->layer_height;
        
        if (p->is_valid() && p->first_point().coincides_with(p->last_point())) {
            // since medial_axis() now returns only Polyline objects, detect loops here
            ExtrusionLoop loop;
            loop.paths.push_back(path);
            coll.append(loop);
        } else {
            coll.append(path);
        }
    }
    
    return coll;
}

void
SurfaceCollection::simplify(double tolerance)
{
    Surfaces ss;
    for (Surfaces::const_iterator it_s = this->surfaces.begin(); it_s != this->surfaces.end(); ++it_s) {
        ExPolygons expp;
        it_s->expolygon.simplify(tolerance, expp);
        for (ExPolygons::const_iterator it_e = expp.begin(); it_e != expp.end(); ++it_e) {
            Surface s = *it_s;
            s.expolygon = *it_e;
            ss.push_back(s);
        }
    }
    this->surfaces = ss;
}

Surfaces
offset(const Surface &surface, const float delta,
    double scale, ClipperLib::JoinType joinType, double miterLimit)
{
    // perform offset
    ExPolygons expp = offset_ex(surface.expolygon, delta, scale, joinType, miterLimit);
    
    // clone the input surface for each expolygon we got
    Surfaces retval;
    retval.reserve(expp.size());
    for (ExPolygons::iterator it = expp.begin(); it != expp.end(); ++it) {
        Surface s = surface;  // clone
        s.expolygon = *it;
        retval.push_back(s);
    }
    return retval;
}

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

inline void expolygons_append(ExPolygons &dst, const ExPolygons &src) 
{ 
    dst.insert(dst.end(), src.begin(), src.end());
}

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.........

void
SVG::draw(const ExPolygons &expolygons, std::string fill)
{
    for (ExPolygons::const_iterator it = expolygons.begin(); it != expolygons.end(); ++it)
        this->draw(*it, fill);
}