Polyholes!

slic3r/Sliç3r#3323
slic3r/Sliç3r#2438
prusa3d/PrusaSlicer#515

src/libslic3r/Print.hpp

@@ -182,6 +182,7 @@ private:
 
     void _slice(const std::vector<coordf_t> &layer_height_profile);
     void _offset_holes(double hole_delta, LayerRegion *layerm);
+    void _transform_hole_to_polyholes();
     void _smooth_curves(LayerRegion *layerm);
     std::string _fix_slicing_errors();
     void _simplify_slices(double distance);

src/libslic3r/PrintConfig.cpp

@@ -1232,6 +1232,7 @@ void PrintConfigDef::init_fff_params()
                    "over the default layer height.");
     def->sidetext = L("mm or %");
     def->ratio_over = "layer_height";
+    def->min = 0;
     def->mode = comAdvanced;
     def->set_default_value(new ConfigOptionFloatOrPercent(0.2, false));
 
@@ -3011,6 +3012,16 @@ void PrintConfigDef::init_fff_params()
     def->mode = comExpert;
     def->set_default_value(new ConfigOptionFloat(0));
 
+    def = this->add("hole_to_polyhole", coBool);
+    def->label = L("Convert round holes to polyholes");
+    def->full_label = L("Convert round holes to polyholes");
+    def->category = L("Slicing");
+    def->tooltip = L("Search for almost-circular holes that span more than one layer and conert the geometry to polyholes."
+        " Use the nozzle size and the (biggest) diameter to compute the polyhole."
+        "\nSee http://hydraraptor.blogspot.com/2011/02/polyholes.html");
+    def->mode = comAdvanced;
+    def->set_default_value(new ConfigOptionBool(false));
+
     def = this->add("z_offset", coFloat);
     def->label = L("Z offset");
     def->tooltip = L("This value will be added (or subtracted) from all the Z coordinates "

src/libslic3r/PrintConfig.hpp

@@ -598,6 +598,7 @@ public:
     ConfigOptionBool                gap_fill;
     ConfigOptionFloatOrPercent      gap_fill_min_area;
     ConfigOptionFloat               gap_fill_speed;
+    ConfigOptionBool                hole_to_polyhole;
     ConfigOptionInt                 infill_extruder;
     ConfigOptionFloatOrPercent      infill_extrusion_width;
     ConfigOptionInt                 infill_every_layers;
@@ -667,6 +668,7 @@ protected:
         OPT_PTR(gap_fill);
         OPT_PTR(gap_fill_min_area);
         OPT_PTR(gap_fill_speed);
+        OPT_PTR(hole_to_polyhole);
         OPT_PTR(infill_extruder);
         OPT_PTR(infill_extrusion_width);
         OPT_PTR(infill_every_layers);

src/libslic3r/PrintObject.cpp

@@ -122,11 +122,127 @@ void PrintObject::slice()
     // Simplify slices if required.
     if (m_print->config().resolution)
         this->_simplify_slices(scale_(this->print()->config().resolution));
+    //create polyholes
+    this->_transform_hole_to_polyholes();
     if (m_layers.empty())
         throw std::runtime_error("No layers were detected. You might want to repair your STL file(s) or check their size or thickness and retry.\n");    
     this->set_done(posSlice);
 }
 
+
+Polygon create_polyhole(const Point center, const coord_t diameter, const coord_t nozzle_diameter)
+{
+    // n = max(round(2 * d), 3); // for 0.4mm nozzle
+    size_t nb_polygons = (int)std::max(3, (int)std::round(2.0 * unscaled(diameter) * 0.4 / unscaled(nozzle_diameter)));
+    // cylinder(h = h, r = (d / 2) / cos (180 / n), $fn = n);
+    Points pts;
+    const float rayon = (diameter / 1) / std::cos(PI / nb_polygons);
+    for (int i = 0; i < nb_polygons; ++i) {
+        float angle = (PI * 2 * i) / nb_polygons;
+        pts.emplace_back(center.x() + rayon * cos(angle), center.y() + rayon * sin(angle));
+    }
+     return Polygon{ pts };
+}
+
+void PrintObject::_transform_hole_to_polyholes()
+{
+    // get all circular holes for each layer
+    // the id is center-diameter-extruderid
+    std::vector<std::vector<std::pair<std::tuple<Point,float, int>, Polygon*>>> layerid2center;
+    for (size_t i = 0; i < this->m_layers.size(); i++) layerid2center.emplace_back();
+    //tbb::parallel_for(
+        //tbb::blocked_range<size_t>(0, m_layers.size()),
+        //[this, layerid2center](const tbb::blocked_range<size_t>& range) {
+        //for (size_t layer_idx = range.begin(); layer_idx < range.end(); ++layer_idx) {
+    for (size_t layer_idx = 0; layer_idx < this->m_layers.size(); ++layer_idx) {
+            m_print->throw_if_canceled();
+            Layer *layer = m_layers[layer_idx];
+            for (size_t region_idx = 0; region_idx < layer->m_regions.size(); ++region_idx)
+            {
+                if (layer->m_regions[region_idx]->region()->config().hole_to_polyhole) {
+                    for (Surface &surf : layer->m_regions[region_idx]->m_slices.surfaces) {
+                        for (Polygon &hole : surf.expolygon.holes) {
+                            //test if convex (as it's clockwise bc it's a hole, we have to do the opposite)
+                            if (hole.convex_points().empty() && hole.points.size() > 4) {
+                                double center_x = 0, center_y = 0;
+                                for (int i = 0; i < hole.points.size(); ++i) {
+                                    center_x += hole.points[i].x();
+                                    center_y += hole.points[i].y();
+                                }
+                                Point center{ center_x / hole.points.size(), center_y / hole.points.size() };
+                                double diameter_min = std::numeric_limits<float>::max(), diameter_max = 0;
+                                for (int i = 0; i < hole.points.size(); ++i) {
+                                    double dist = hole.points[i].distance_to_square(center);
+                                    diameter_min = std::min(diameter_min, dist);
+                                    diameter_max = std::max(diameter_max, dist);
+                                }
+                                diameter_min = std::sqrt(diameter_min);
+                                diameter_max = std::sqrt(diameter_max);
+                                if (diameter_max - diameter_min < SCALED_EPSILON) {
+                                    layerid2center[layer_idx].emplace_back(
+                                        std::tuple<Point, float, int>{center, diameter_max, layer->m_regions[region_idx]->region()->config().perimeter_extruder.value}, &hole);
+                                }
+                            }
+                        }
+                    }
+                }
+            }
+            // for layer->slices, it will be also replaced later.
+        }
+    //});
+    //sort holes per center-diameter
+    std::map<std::tuple<Point, float, int>,std::vector<std::pair<Polygon*,int>>> id2layerz2hole;
+
+    //search & find hole that span at least X layers
+    const size_t min_nb_layers = 2;
+    float max_layer_height = config().layer_height * 2;
+    for (size_t layer_idx = 0; layer_idx < this->m_layers.size(); ++layer_idx) {
+        for (size_t hole_idx = 0; hole_idx < layerid2center[layer_idx].size(); ++hole_idx) {
+            //get all other same polygons
+            std::tuple<Point, float, int> &id = layerid2center[layer_idx][hole_idx].first;
+            float max_z = layers()[layer_idx]->print_z;
+            std::vector<std::pair<Polygon*,int>> holes;
+            holes.emplace_back(layerid2center[layer_idx][hole_idx].second, layer_idx);
+            for (size_t search_layer_idx = layer_idx + 1; search_layer_idx < this->m_layers.size(); ++search_layer_idx) {
+                if (layers()[search_layer_idx]->print_z - layers()[search_layer_idx]->height - max_z > EPSILON) break;
+                //search an other polygon with same id
+                for (size_t search_hole_idx = 0; search_hole_idx < layerid2center[search_layer_idx].size(); ++search_hole_idx) {
+                    std::tuple<Point, float, int> &search_id = layerid2center[search_layer_idx][search_hole_idx].first;
+                    if (std::get<0>(id).distance_to(std::get<0>(search_id)) < SCALED_EPSILON
+                        && std::abs(std::get<1>(id) - std::get<1>(search_id)) < SCALED_EPSILON
+                        && std::get<2>(id) == std::get<2>(search_id)) {
+                        max_z = layers()[search_layer_idx]->print_z;
+                        holes.emplace_back(layerid2center[search_layer_idx][search_hole_idx].second, search_layer_idx);
+                        layerid2center[search_layer_idx].erase(layerid2center[search_layer_idx].begin() + search_hole_idx);
+                        search_hole_idx--;
+                        break;
+                    }
+                }
+            }
+            if (holes.size() >= min_nb_layers) {
+                id2layerz2hole.emplace(std::move(id), std::move(holes));
+            }
+        }
+    }
+    //create a polyhole per id and replace holes points by it.
+    for (auto entry : id2layerz2hole) {
+        Polygon polyhole = create_polyhole(std::get<0>(entry.first), std::get<1>(entry.first), scale_(print()->config().nozzle_diameter.get_at(std::get<2>(entry.first) - 1)));
+        polyhole.make_clockwise();
+        for (auto &poly_to_replace : entry.second) {
+            //search the clone in layers->slices
+            for (ExPolygon &explo_slice : m_layers[poly_to_replace.second]->slices.expolygons) {
+                for (Polygon &poly_slice : explo_slice.holes) {
+                    if (poly_slice.points == poly_to_replace.first->points) {
+                        poly_slice.points = polyhole.points;
+                    }
+                }
+            }
+            // copy
+            poly_to_replace.first->points = polyhole.points;
+        }
+    }
+}
+
 // 1) Merges typed region slices into stInternal type.
 // 2) Increases an "extra perimeters" counter at region slices where needed.
 // 3) Generates perimeters, gap fills and fill regions (fill regions of type stInternal).
@@ -500,7 +616,8 @@ bool PrintObject::invalidate_state_by_config_options(const std::vector<t_config_
             || opt_key == "support_material_contact_distance_top" 
             || opt_key == "support_material_contact_distance_bottom" 
             || opt_key == "xy_size_compensation"
-            || opt_key == "hole_size_compensation") {
+            || opt_key == "hole_size_compensation"
+            || opt_key == "hole_to_polyhole") {
             steps.emplace_back(posSlice);
         } else if (opt_key == "support_material") {
             steps.emplace_back(posSupportMaterial);

src/libslic3r/Slicing.cpp

@@ -47,7 +47,7 @@ SlicingParameters SlicingParameters::create_from_config(
 	coordf_t				 object_height,
 	const std::vector<unsigned int> &object_extruders)
 {
-    coordf_t first_layer_height                      = (object_config.first_layer_height.value <= 0) ? 
+    coordf_t first_layer_height                      = (object_config.first_layer_height.get_abs_value(object_config.layer_height.value) <= 0) ?
         object_config.layer_height.value : 
         object_config.first_layer_height.get_abs_value(object_config.layer_height.value);
     // If object_config.support_material_extruder == 0 resp. object_config.support_material_interface_extruder == 0,

src/slic3r/GUI/Preset.cpp

@@ -426,7 +426,9 @@ const std::vector<std::string>& Preset::print_options()
         "top_infill_extrusion_width", "support_material_extrusion_width", "infill_overlap", "bridge_flow_ratio", 
         "clip_multipart_objects",
         "over_bridge_flow_ratio", "clip_multipart_objects", "enforce_full_fill_volume", "external_infill_margin", "bridged_infill_margin",
-        "elefant_foot_compensation", "xy_size_compensation", "hole_size_compensation", "threads", "resolution",
+        "elefant_foot_compensation", "xy_size_compensation", "hole_size_compensation", 
+        "hole_to_polyhole",
+        "threads", "resolution",
         "wipe_tower", "wipe_tower_x", "wipe_tower_y", "wipe_tower_width", "wipe_tower_rotation_angle", "wipe_tower_bridging",
         "single_extruder_multi_material_priming", "compatible_printers", "compatible_printers_condition", "inherits", 
         "infill_dense", "infill_dense_algo",

src/slic3r/GUI/Tab.cpp

@@ -1109,6 +1109,8 @@ void TabPrint::build()
         line.append_option(optgroup->get_option("hole_size_compensation"));
         optgroup->append_line(line);
 
+        optgroup->append_single_option_line("hole_to_polyhole");
+
         optgroup = page->new_optgroup(_(L("Other")));
         optgroup->append_single_option_line("clip_multipart_objects");