fix: spaghetti infill now uses connected zigzags to minimize non-extrusion moves (CURA-3238)

also note that due to the spaghetti_inset the zigzags are not connected to the walls (depending on user input)

.gitignore

@@ -7,14 +7,8 @@
 NUL
 *.gcode
 
-## Directories used for other stuff
-Trash/*
-output/*
-callgrind/*
-
 ## Building result.
 build/*
-debug_build/*
 *.pyc
 *.exe
 *.a

CMakeLists.txt

@@ -91,6 +91,7 @@ set(engine_SRCS # Except main.cpp.
     src/Wireframe2gcode.cpp
 
     src/infill/NoZigZagConnectorProcessor.cpp
+    src/infill/SpaghettiInfill.cpp
     src/infill/ZigzagConnectorProcessorConnectedEndPieces.cpp
     src/infill/ZigzagConnectorProcessorDisconnectedEndPieces.cpp
     src/infill/ZigzagConnectorProcessorEndPieces.cpp
@@ -106,7 +107,6 @@ set(engine_SRCS # Except main.cpp.
     src/progress/Progress.cpp
     src/progress/ProgressStageEstimator.cpp
 
-    src/settings/PathConfigStorage.cpp
     src/settings/SettingConfig.cpp
     src/settings/SettingContainer.cpp
     src/settings/SettingRegistry.cpp

src/FffGcodeWriter.h

@@ -74,19 +74,18 @@ private:
 
     std::vector<FanSpeedLayerTimeSettings> fan_speed_layer_time_settings_per_extruder; //!< The settings used relating to minimal layer time and fan speeds. Configured for each extruder.
 
-
-    GCodePlanner::PlanningState planner_state;
-
+    Point last_position_planned; //!< The position of the head before planning the next layer
+    int current_extruder_planned; //!< The extruder train in use before planning the next layer
+    bool is_inside_mesh_layer_part; //!< Whether the last position was inside a layer part (used in combing)
 public:
     FffGcodeWriter(SettingsBase* settings_)
     : SettingsMessenger(settings_)
     , max_object_height(0)
     , layer_plan_buffer(this, gcode)
     , extruder_prime_is_planned {} // initialize all values in array with [false]
-    , planner_state{ no_point
-                    , 0 // changed somewhere early in FffGcodeWriter::writeGCode
-                    , false
-                    }
+    , last_position_planned(no_point)
+    , current_extruder_planned(0) // changed somewhere early in FffGcodeWriter::writeGCode
+    , is_inside_mesh_layer_part(false)
     {
     }
 
@@ -173,6 +172,17 @@ private:
      * \param[out] storage The data storage to which to save the configurations
      */
     void setConfigRetraction(SliceDataStorage& storage);
+    
+    /*!
+     * Initialize the GcodePathConfig config parameters which don't change over
+     * all layers, for each feature.
+     * 
+     * The features are: skirt or brim, support and for each mesh: outer wall,
+     * inner walls, skin, infill (and combined infill).
+     * 
+     * \param[out] storage The data storage to which to save the configurations.
+     */
+    void initConfigs(SliceDataStorage& storage);
 
     /*!
      * Get the extruder with which to start the print.
@@ -182,7 +192,7 @@ private:
      * 
      * \param[in] storage where to get settings from.
      */
-    unsigned int getStartExtruder(const SliceDataStorage& storage);
+    unsigned int getStartExtruder(SliceDataStorage& storage);
 
     /*!
      * Set temperatures and perform initial priming.
@@ -192,14 +202,14 @@ private:
      * \param[in] storage where the slice data is stored.
      * \param[in] start_extruder_nr The extruder with which to start the print.
      */
-    void processStartingCode(const SliceDataStorage& storage, const unsigned int start_extruder_nr);
+    void processStartingCode(SliceDataStorage& storage, const unsigned int start_extruder_nr);
 
     /*!
      * Move up and over the already printed meshgroups to print the next meshgroup.
      * 
      * \param[in] storage where the slice data is stored.
      */
-    void processNextMeshGroupCode(const SliceDataStorage& storage);
+    void processNextMeshGroupCode(SliceDataStorage& storage);
     
     /*!
      * Add raft layer plans onto the FffGcodeWriter::layer_plan_buffer
@@ -207,7 +217,7 @@ private:
      * \param[in,out] storage where the slice data is stored.
      * \param total_layers The total number of layers.
      */
-    void processRaft(const SliceDataStorage& storage, unsigned int total_layers);
+    void processRaft(SliceDataStorage& storage, unsigned int total_layers);
 
     /*!
      * Convert the polygon data of a layer into a layer plan on the FffGcodeWriter::layer_plan_buffer
@@ -218,16 +228,15 @@ private:
      * \param[in] storage where the slice data is stored.
      * \param layer_nr The index of the layer to write the gcode of.
      * \param total_layers The total number of layers.
-     * \return The layer plans
      */
-    GCodePlanner& processLayer(const SliceDataStorage& storage, int layer_nr, unsigned int total_layers) const;
+    void processLayer(SliceDataStorage& storage, int layer_nr, unsigned int total_layers);
 
     /*!
      * Whether the extruders need to be primed separately just before they are used.
      * 
      * \return whether the extruders need to be primed separately just before they are used
      */
-    bool getExtrudersNeedPrimeDuringFirstLayer() const;
+    bool getExtrudersNeedPrimeDuringFirstLayer();
 
     /*!
      * Plan priming of all used extruders which haven't been primed yet
@@ -235,7 +244,7 @@ private:
      * \param layer_plan The initial planning of the g-code of the layer.
      * \param layer_nr The index of the layer to write the gcode of.
      */
-    void ensureAllExtrudersArePrimed(const SliceDataStorage& storage, GCodePlanner& layer_plan, const int layer_nr) const;
+    void ensureAllExtrudersArePrimed(SliceDataStorage& storage, GCodePlanner& layer_plan, const int layer_nr);
 
     /*!
      * Add the skirt or the brim to the layer plan \p gcodeLayer.
@@ -245,7 +254,7 @@ private:
      * \param extruder_nr The extruder train for which to process the skirt or
      * brim.
      */
-    void processSkirtBrim(const SliceDataStorage& storage, GCodePlanner& gcodeLayer, unsigned int extruder_nr) const;
+    void processSkirtBrim(SliceDataStorage& storage, GCodePlanner& gcodeLayer, unsigned int extruder_nr);
     
     /*!
      * Adds the ooze shield to the layer plan \p gcodeLayer.
@@ -254,7 +263,7 @@ private:
      * \param gcodeLayer The initial planning of the gcode of the layer.
      * \param layer_nr The index of the layer to write the gcode of.
      */
-    void processOozeShield(const SliceDataStorage& storage, GCodePlanner& gcodeLayer, unsigned int layer_nr) const;
+    void processOozeShield(SliceDataStorage& storage, GCodePlanner& gcodeLayer, unsigned int layer_nr);
     
     /*!
      * Adds the draft protection screen to the layer plan \p gcodeLayer.
@@ -263,7 +272,7 @@ private:
      * \param gcodeLayer The initial planning of the gcode of the layer.
      * \param layer_nr The index of the layer to write the gcode of.
      */
-    void processDraftShield(const SliceDataStorage& storage, GCodePlanner& gcodeLayer, unsigned int layer_nr) const;
+    void processDraftShield(SliceDataStorage& storage, GCodePlanner& gcodeLayer, unsigned int layer_nr);
 
     /*!
      * Calculate in which order to plan the extruders
@@ -272,7 +281,7 @@ private:
      * \param current_extruder The current extruder with which we last printed
      * \return A vector of pairs of extruder numbers coupled with the mesh indices ordered on print order for that extruder.
      */
-    std::vector<int> calculateExtruderOrder(const SliceDataStorage& storage, int current_extruder) const;
+    std::vector<int> calculateExtruderOrder(SliceDataStorage& storage, int current_extruder);
 
     /*!
      * Calculate in which order to plan the meshes of a specific extruder
@@ -281,95 +290,114 @@ private:
      * \param extruder_nr The extruder for which to determine the order
      * \return A vector of pairs of extruder numbers coupled with the mesh indices ordered on print order for that extruder.
      */
-    std::vector<unsigned int> calculateMeshOrder(const SliceDataStorage& storage, int extruder_nr) const;
+    std::vector<unsigned int> calculateMeshOrder(SliceDataStorage& storage, int extruder_nr);
 
     /*!
      * Add a single layer from a single mesh-volume to the layer plan \p gcodeLayer in mesh surface mode.
      * 
      * \param[in] storage where the slice data is stored.
      * \param mesh The mesh to add to the layer plan \p gcodeLayer.
-     * \param mesh_config the line config with which to print a print feature
      * \param gcodeLayer The initial planning of the gcode of the layer.
      * \param layer_nr The index of the layer to write the gcode of.
      * 
      */
-    void addMeshLayerToGCode_meshSurfaceMode(const SliceDataStorage& storage, const SliceMeshStorage* mesh, const PathConfigStorage::MeshPathConfigs& mesh_config, GCodePlanner& gcodeLayer, int layer_nr) const;
+    void addMeshLayerToGCode_meshSurfaceMode(SliceDataStorage& storage, SliceMeshStorage* mesh, GCodePlanner& gcodeLayer, int layer_nr);
     
     /*!
      * Add the open polylines from a single layer from a single mesh-volume to the layer plan \p gcodeLayer for mesh the surface modes.
      * 
      * \param[in] storage where the slice data is stored.
      * \param mesh The mesh for which to add to the layer plan \p gcodeLayer.
-     * \param mesh_config the line config with which to print a print feature
      * \param gcodeLayer The initial planning of the gcode of the layer.
      * \param layer_nr The index of the layer to write the gcode of.
      * 
      */
-    void addMeshOpenPolyLinesToGCode(const SliceDataStorage& storage, const SliceMeshStorage* mesh, const PathConfigStorage::MeshPathConfigs& mesh_config, GCodePlanner& gcode_layer, int layer_nr) const;
+    void addMeshOpenPolyLinesToGCode(SliceDataStorage& storage, SliceMeshStorage* mesh, GCodePlanner& gcode_layer, int layer_nr);
     
     /*!
      * Add a single layer from a single mesh-volume to the layer plan \p gcode_layer.
      * 
      * \param[in] storage where the slice data is stored.
      * \param mesh The mesh to add to the layer plan \p gcode_layer.
-     * \param mesh_config the line config with which to print a print feature
      * \param gcode_layer The initial planning of the gcode of the layer.
      * \param layer_nr The index of the layer to write the gcode of.
      * 
      */
-    void addMeshLayerToGCode(const SliceDataStorage& storage, const SliceMeshStorage* mesh, const PathConfigStorage::MeshPathConfigs& mesh_config, GCodePlanner& gcode_layer, int layer_nr) const;
+    void addMeshLayerToGCode(SliceDataStorage& storage, SliceMeshStorage* mesh, GCodePlanner& gcode_layer, int layer_nr);
 
     /*!
      * Add a single part from a given layer of a mesh-volume to the layer plan \p gcode_layer.
      * 
      * \param[in] storage where the slice data is stored.
      * \param mesh The mesh to add to the layer plan \p gcode_layer.
-     * \param mesh_config the line config with which to print a print feature
      * \param part The part to add
      * \param gcode_layer The initial planning of the gcode of the layer.
      * \param layer_nr The index of the layer to write the gcode of.
      * 
      */
-    void addMeshPartToGCode(const SliceDataStorage& storage, const SliceMeshStorage* mesh, const PathConfigStorage::MeshPathConfigs& mesh_config, const SliceLayerPart& part, GCodePlanner& gcode_layer, int layer_nr) const;
-    
+    void addMeshPartToGCode(SliceDataStorage& storage, SliceMeshStorage* mesh, SliceLayerPart& part, GCodePlanner& gcode_layer, int layer_nr);
+
+    /*!
+     * Add sparse infill for a given part in a layer plan.
+     * 
+     * \param gcodeLayer The initial planning of the gcode of the layer.
+     * \param mesh The mesh for which to add to the layer plan \p gcodeLayer.
+     * \param part The part for which to create gcode
+     * \param layer_nr The current layer number.
+     * \param infill_line_distance The distance between the infill lines
+     * \param infill_overlap The distance by which the infill overlaps with the wall insets.
+     * \param fillAngle The angle in the XY plane at which the infill is generated.
+     */
+    void processInfill(GCodePlanner& gcodeLayer, SliceMeshStorage* mesh, SliceLayerPart& part, unsigned int layer_nr, int infill_line_distance, int infill_overlap, int fillAngle); 
+
+    /*!
+     * Add spaghetti infill for a given part in a layer plan.
+     * 
+     * \param gcodeLayer The initial planning of the gcode of the layer.
+     * \param mesh The mesh for which to add to the layer plan \p gcodeLayer.
+     * \param part The part for which to create gcode
+     * \param layer_nr The current layer number.
+     * \param infill_line_distance The distance between the infill lines
+     * \param infill_overlap The distance by which the infill overlaps with the wall insets.
+     * \param fillAngle The angle in the XY plane at which the infill is generated.
+     */
+    void processSpaghettiInfill(GCodePlanner& gcodeLayer, SliceMeshStorage* mesh, SliceLayerPart& part, unsigned int layer_nr, int infill_line_distance, int infill_overlap, int fillAngle); 
+
     /*!
      * Add thicker (multiple layers) sparse infill for a given part in a layer plan.
      * 
      * \param gcodeLayer The initial planning of the gcode of the layer.
      * \param mesh The mesh for which to add to the layer plan \p gcodeLayer.
-     * \param mesh_config the line config with which to print a print feature
      * \param part The part for which to create gcode
      * \param layer_nr The current layer number.
      * \param infill_line_distance The distance between the infill lines
      * \param infill_overlap The distance by which the infill overlaps with the wall insets.
      * \param fillAngle The angle in the XY plane at which the infill is generated.
      */
-    void processMultiLayerInfill(GCodePlanner& gcodeLayer, const SliceMeshStorage* mesh, const PathConfigStorage::MeshPathConfigs& mesh_config, const SliceLayerPart& part, unsigned int layer_nr, int infill_line_distance, int infill_overlap, int fillAngle) const;
+    void processMultiLayerInfill(GCodePlanner& gcodeLayer, SliceMeshStorage* mesh, SliceLayerPart& part, unsigned int layer_nr, int infill_line_distance, int infill_overlap, int fillAngle); 
     
     /*!
      * Add normal sparse infill for a given part in a layer.
      * \param gcodeLayer The initial planning of the gcode of the layer.
      * \param mesh The mesh for which to add to the layer plan \p gcodeLayer.
-     * \param mesh_config the line config with which to print a print feature
      * \param part The part for which to create gcode
      * \param layer_nr The current layer number.
      * \param infill_line_distance The distance between the infill lines
      * \param infill_overlap The distance by which the infill overlaps with the wall insets.
      * \param fillAngle The angle in the XY plane at which the infill is generated.
      */
-    void processSingleLayerInfill(GCodePlanner& gcodeLayer, const SliceMeshStorage* mesh, const PathConfigStorage::MeshPathConfigs& mesh_config, const SliceLayerPart& part, unsigned int layer_nr, int infill_line_distance, int infill_overlap, int fillAngle) const;
+    void processSingleLayerInfill(GCodePlanner& gcodeLayer, SliceMeshStorage* mesh, SliceLayerPart& part, unsigned int layer_nr, int infill_line_distance, int infill_overlap, int fillAngle);
     
     /*!
      * Generate the insets for the walls of a given layer part.
      * \param gcodeLayer The initial planning of the gcode of the layer.
      * \param mesh The mesh for which to add to the layer plan \p gcodeLayer.
-     * \param mesh_config the line config with which to print a print feature
      * \param part The part for which to create gcode
      * \param layer_nr The current layer number.
      * \param z_seam_type dir3ective for where to start the outer paerimeter of a part
      * \param z_seam_pos The location near where to start the outer inset in case \p z_seam_type is 'back'
      */
-    void processInsets(GCodePlanner& gcodeLayer, const SliceMeshStorage* mesh, const PathConfigStorage::MeshPathConfigs& mesh_config, const SliceLayerPart& part, unsigned int layer_nr, EZSeamType z_seam_type, Point z_seam_pos) const;
+    void processInsets(GCodePlanner& gcodeLayer, SliceMeshStorage* mesh, SliceLayerPart& part, unsigned int layer_nr, EZSeamType z_seam_type, Point z_seam_pos);
     
     
     /*!
@@ -380,13 +408,12 @@ private:
      * 
      * \param gcodeLayer The initial planning of the gcode of the layer.
      * \param mesh The mesh for which to add to the layer plan \p gcodeLayer.
-     * \param mesh_config the line config with which to print a print feature
      * \param part The part for which to create gcode
      * \param layer_nr The current layer number.
      * \param skin_overlap The distance by which the skin overlaps with the wall insets and the distance by which the perimeter gaps overlap with adjacent print features.
      * \param fillAngle The angle in the XY plane at which the infill is generated.
      */
-    void processSkinAndPerimeterGaps(GCodePlanner& gcode_layer, const SliceMeshStorage* mesh, const PathConfigStorage::MeshPathConfigs& mesh_config, const SliceLayerPart& part, unsigned int layer_nr, int skin_overlap, int infill_angle) const;
+    void processSkinAndPerimeterGaps(cura::GCodePlanner& gcode_layer, cura::SliceMeshStorage* mesh, cura::SliceLayerPart& part, unsigned int layer_nr, int skin_overlap, int infill_angle);
 
     /*!
      * Add the support to the layer plan \p gcodeLayer of the current layer for all support parts with the given \p extruder_nr.
@@ -395,7 +422,7 @@ private:
      * \param layer_nr The index of the layer to write the gcode of.
      * \return whether any support was added to the layer plan
      */
-    bool addSupportToGCode(const SliceDataStorage& storage, GCodePlanner& gcodeLayer, int layer_nr, int extruder_nr) const;
+    bool addSupportToGCode(SliceDataStorage& storage, GCodePlanner& gcodeLayer, int layer_nr, int extruder_nr);
     /*!
      * Add the support lines/walls to the layer plan \p gcodeLayer of the current layer.
      * \param[in] storage where the slice data is stored.
@@ -403,7 +430,7 @@ private:
      * \param layer_nr The index of the layer to write the gcode of.
      * \return whether any support infill was added to the layer plan
      */
-    bool addSupportInfillToGCode(const SliceDataStorage& storage, GCodePlanner& gcodeLayer, int layer_nr) const;
+    bool addSupportInfillToGCode(SliceDataStorage& storage, GCodePlanner& gcodeLayer, int layer_nr);
     /*!
      * Add the support skins to the layer plan \p gcodeLayer of the current layer.
      * \param[in] storage where the slice data is stored.
@@ -411,7 +438,7 @@ private:
      * \param layer_nr The index of the layer to write the gcode of.
      * \return whether any support skin was added to the layer plan
      */
-    bool addSupportRoofsToGCode(const SliceDataStorage& storage, GCodePlanner& gcodeLayer, int layer_nr) const;
+    bool addSupportRoofsToGCode(SliceDataStorage& storage, GCodePlanner& gcodeLayer, int layer_nr);
     
     /*!
      * Change to a new extruder, and add the prime tower instructions if the new extruder is different from the last.
@@ -423,7 +450,7 @@ private:
      * \param layer_nr The index of the layer to write the gcode of.
      * \param extruder_nr The extruder to which to switch
      */
-    void setExtruder_addPrime(const SliceDataStorage& storage, GCodePlanner& gcode_layer, int layer_nr, int extruder_nr) const;
+    void setExtruder_addPrime(SliceDataStorage& storage, GCodePlanner& gcode_layer, int layer_nr, int extruder_nr);
     
     /*!
      * Add the prime tower gcode for the current layer.
@@ -432,7 +459,7 @@ private:
      * \param layer_nr The index of the layer to write the gcode of.
      * \param prev_extruder The current extruder with which we last printed.
      */
-    void addPrimeTower(const SliceDataStorage& storage, GCodePlanner& gcodeLayer, int layer_nr, int prev_extruder) const;
+    void addPrimeTower(SliceDataStorage& storage, GCodePlanner& gcodeLayer, int layer_nr, int prev_extruder);
     
     /*!
      * Add the end gcode and set all temperatures to zero.

src/FffPolygonGenerator.cpp

@@ -2,7 +2,6 @@
 
 #include <algorithm>
 #include <map> // multimap (ordered map allowing duplicate keys)
-#include <omp.h>
 
 #include "utils/math.h"
 #include "utils/algorithm.h"
@@ -16,6 +15,7 @@
 #include "WallsComputation.h"
 #include "SkirtBrim.h"
 #include "skin.h"
+#include "infill/SpaghettiInfill.h"
 #include "infill.h"
 #include "raft.h"
 #include "progress/Progress.h"
@@ -346,24 +346,12 @@ void FffPolygonGenerator::processBasicWallsSkinInfill(SliceDataStorage& storage,
     
     
     // walls
-    unsigned int processed_layer_count = 0;
-#pragma omp parallel for default(none) shared(mesh_layer_count, mesh, inset_skin_progress_estimate, processed_layer_count) schedule(dynamic)
     for (unsigned int layer_number = 0; layer_number < mesh.layers.size(); layer_number++)
     {
         logDebug("Processing insets for layer %i of %i\n", layer_number, mesh_layer_count);
         processInsets(mesh, layer_number);
-#ifdef _OPENMP
-        if (omp_get_thread_num() == 0)
-#endif
-        { // progress estimation is done only in one thread so that no two threads message progress at the same time
-            int _processed_layer_count;
-#pragma omp atomic read
-                _processed_layer_count = processed_layer_count;
-            double progress = inset_skin_progress_estimate.progress(_processed_layer_count);
-            Progress::messageProgress(Progress::Stage::INSET_SKIN, progress * 100, 100);
-        }
-#pragma omp atomic
-        processed_layer_count++;
+        double progress = inset_skin_progress_estimate.progress(layer_number);
+        Progress::messageProgress(Progress::Stage::INSET_SKIN, progress * 100, 100);
     }
 
     ProgressEstimatorLinear* skin_estimator = new ProgressEstimatorLinear(mesh_layer_count);
@@ -394,33 +382,16 @@ void FffPolygonGenerator::processBasicWallsSkinInfill(SliceDataStorage& storage,
     {
         mesh_max_bottom_layer_count = std::max(mesh_max_bottom_layer_count, mesh.getSettingAsCount("bottom_layers"));
     }
-
-    processed_layer_count = 0;
-#pragma omp parallel default(none) shared(mesh_layer_count, mesh, mesh_max_bottom_layer_count, process_infill, inset_skin_progress_estimate, processed_layer_count)
+    for (unsigned int layer_number = 0; layer_number < mesh.layers.size(); layer_number++)
     {
-
-#pragma omp for schedule(dynamic)
-        for (unsigned int layer_number = 0; layer_number < mesh.layers.size(); layer_number++)
+        logDebug("Processing skins and infill layer %i of %i\n", layer_number, mesh_layer_count);
+        if (!mesh.getSettingBoolean("magic_spiralize") || static_cast<int>(layer_number) < mesh_max_bottom_layer_count)    //Only generate up/downskin and infill for the first X layers when spiralize is choosen.
         {
-            logDebug("Processing skins and infill layer %i of %i\n", layer_number, mesh_layer_count);
-            if (!mesh.getSettingBoolean("magic_spiralize") || static_cast<int>(layer_number) < mesh_max_bottom_layer_count)    //Only generate up/downskin and infill for the first X layers when spiralize is choosen.
-            {
-                processSkinsAndInfill(mesh, layer_number, process_infill);
-            }
-#ifdef _OPENMP
-            if (omp_get_thread_num() == 0)
-#endif
-            { // progress estimation is done only in one thread so that no two threads message progress at the same time
-                int _processed_layer_count;
-#pragma omp atomic read
-                    _processed_layer_count = processed_layer_count;
-                double progress = inset_skin_progress_estimate.progress(_processed_layer_count);
-                Progress::messageProgress(Progress::Stage::INSET_SKIN, progress * 100, 100);
-            }
-#pragma omp atomic
-                processed_layer_count++;
-        }
+            processSkinsAndInfill(mesh, layer_number, process_infill);
         }
+        double progress = inset_skin_progress_estimate.progress(layer_number);
+        Progress::messageProgress(Progress::Stage::INSET_SKIN, progress * 100, 100);
+    }
 }
 
 void FffPolygonGenerator::processInfillMesh(SliceDataStorage& storage, unsigned int mesh_order_idx, std::vector<unsigned int>& mesh_order)
@@ -496,18 +467,27 @@ void FffPolygonGenerator::processInfillMesh(SliceDataStorage& storage, unsigned
 
 void FffPolygonGenerator::processDerivedWallsSkinInfill(SliceMeshStorage& mesh)
 {
-    // create gradual infill areas
-    SkinInfillAreaComputation::generateGradualInfill(mesh, mesh.getSettingInMicrons("gradual_infill_step_height"), mesh.getSettingAsCount("gradual_infill_steps"));
-
-    //SubDivCube Pre-compute Octree
-    if (mesh.getSettingAsFillMethod("infill_pattern") == EFillMethod::CUBICSUBDIV)
+    // generate spaghetti infill filling areas and volumes
+    if (mesh.getSettingBoolean("spaghetti_infill_enabled"))
     {
-        SubDivCube::precomputeOctree(mesh);
+        SpaghettiInfill::generateSpaghettiInfill(mesh);
     }
+    else
+    {
 
-    // combine infill
-    unsigned int combined_infill_layers = std::max(1U, round_divide(mesh.getSettingInMicrons("infill_sparse_thickness"), std::max(getSettingInMicrons("layer_height"), (coord_t)1))); //How many infill layers to combine to obtain the requested sparse thickness.
-    combineInfillLayers(mesh,combined_infill_layers);
+        // create gradual infill areas
+        SkinInfillAreaComputation::generateGradualInfill(mesh, mesh.getSettingInMicrons("gradual_infill_step_height"), mesh.getSettingAsCount("gradual_infill_steps"));
+
+        //SubDivCube Pre-compute Octree
+        if (mesh.getSettingAsFillMethod("infill_pattern") == EFillMethod::CUBICSUBDIV)
+        {
+            SubDivCube::precomputeOctree(mesh);
+        }
+
+        // combine infill
+        unsigned int combined_infill_layers = std::max(1U, round_divide(mesh.getSettingInMicrons("infill_sparse_thickness"), std::max(getSettingInMicrons("layer_height"), (coord_t)1))); //How many infill layers to combine to obtain the requested sparse thickness.
+        combineInfillLayers(mesh,combined_infill_layers);
+    }
 
     // fuzzy skin
     if (mesh.getSettingBoolean("magic_fuzzy_skin_enabled"))
@@ -516,12 +496,6 @@ void FffPolygonGenerator::processDerivedWallsSkinInfill(SliceMeshStorage& mesh)
     }
 }
 
-/*
- * This function is executed in a parallel region based on layer_nr.
- * When modifying make sure any changes does not introduce data races.
- *
- * processInsets only reads and writes data for the current layer
- */
 void FffPolygonGenerator::processInsets(SliceMeshStorage& mesh, unsigned int layer_nr) 
 {
     SliceLayer* layer = &mesh.layers[layer_nr];
@@ -603,18 +577,8 @@ void FffPolygonGenerator::removeEmptyFirstLayers(SliceDataStorage& storage, cons
         support_layers.erase(support_layers.begin(), support_layers.begin() + n_empty_first_layers);
     }
 }
-
-/*
- * This function is executed in a parallel region based on layer_nr.
- * When modifying make sure any changes does not introduce data races.
- *
- * generateSkins read (depend on) data from mesh.layers[*].parts[*].insets and write mesh.layers[n].parts[*].skin_parts
- * generateInfill read mesh.layers[n].parts[*].{insets,skin_parts,boundingBox} and write mesh.layers[n].parts[*].infill_area
- *
- * processSkinsAndInfill read (depend on) mesh.layers[*].parts[*].{insets,boundingBox}.
- *                       write mesh.layers[n].parts[*].{skin_parts,infill_area}.
- */
-void FffPolygonGenerator::processSkinsAndInfill(SliceMeshStorage& mesh, unsigned int layer_nr, bool process_infill)
+  
+void FffPolygonGenerator::processSkinsAndInfill(SliceMeshStorage& mesh, unsigned int layer_nr, bool process_infill) 
 {
     if (mesh.getSettingAsSurfaceMode("magic_mesh_surface_mode") == ESurfaceMode::SURFACE) 
     { 

src/GCodePathConfig.cpp

@@ -6,74 +6,105 @@
 namespace cura 
 {
 
-GCodePathConfig::GCodePathConfig(const GCodePathConfig& other)
-: type(other.type)
-, speed_derivatives(other.speed_derivatives)
-, line_width(other.line_width)
-, layer_thickness(other.layer_thickness)
-, flow(other.flow)
-, extrusion_mm3_per_mm(other.extrusion_mm3_per_mm)
+GCodePathConfig::BasicConfig::BasicConfig()
+: speed(0)
+, acceleration(0)
+, jerk(0)
+, line_width(0)
+, flow(100)
 {
 }
 
 
-
-GCodePathConfig::GCodePathConfig(PrintFeatureType type, int line_width, int layer_height, double flow, GCodePathConfig::SpeedDerivatives speed_derivatives)
-: type(type)
-, speed_derivatives(speed_derivatives)
+GCodePathConfig::BasicConfig::BasicConfig(double speed, double acceleration, double jerk, int line_width, double flow)
+: speed(speed)
+, acceleration(acceleration)
+, jerk(jerk)
 , line_width(line_width)
-, layer_thickness(layer_height)
 , flow(flow)
-, extrusion_mm3_per_mm(calculateExtrusion())
 {
 }
 
-void GCodePathConfig::smoothSpeed(GCodePathConfig::SpeedDerivatives first_layer_config, int layer_nr, int max_speed_layer_nr) 
+void GCodePathConfig::BasicConfig::set(double speed, double acceleration, double jerk, int line_width, double flow)
 {
-    double max_speed_layer = max_speed_layer_nr;
-    speed_derivatives.speed = (speed_derivatives.speed * layer_nr) / max_speed_layer + (first_layer_config.speed * (max_speed_layer - layer_nr) / max_speed_layer);
-    speed_derivatives.acceleration = (speed_derivatives.acceleration * layer_nr) / max_speed_layer + (first_layer_config.acceleration * (max_speed_layer - layer_nr) / max_speed_layer);
-    speed_derivatives.jerk = (speed_derivatives.jerk * layer_nr) / max_speed_layer + (first_layer_config.jerk * (max_speed_layer - layer_nr) / max_speed_layer);
+    this->speed = speed;
+    this->acceleration = acceleration;
+    this->jerk = jerk;
+    this->line_width = line_width;
+    this->flow = flow;
 }
 
-double GCodePathConfig::getExtrusionMM3perMM() const
+
+GCodePathConfig::GCodePathConfig(PrintFeatureType type)
+: extrusion_mm3_per_mm(0.0)
+, type(type)
+{
+}
+
+void GCodePathConfig::init(double speed, double acceleration, double jerk, int line_width, double flow)
+{
+    iconic_config.set(speed, acceleration, jerk, line_width, flow);
+    current_config = iconic_config;
+}
+
+void GCodePathConfig::setLayerHeight(int layer_height)
+{
+    this->layer_thickness = layer_height;
+    calculateExtrusion();
+}
+
+void GCodePathConfig::smoothSpeed(GCodePathConfig::BasicConfig first_layer_config, int layer_nr, double max_speed_layer) 
+{
+    current_config.speed = (iconic_config.speed * layer_nr) / max_speed_layer + (first_layer_config.speed * (max_speed_layer - layer_nr) / max_speed_layer);
+    current_config.acceleration = (iconic_config.acceleration * layer_nr) / max_speed_layer + (first_layer_config.acceleration * (max_speed_layer - layer_nr) / max_speed_layer);
+    current_config.jerk = (iconic_config.jerk * layer_nr) / max_speed_layer + (first_layer_config.jerk * (max_speed_layer - layer_nr) / max_speed_layer);
+}
+
+void GCodePathConfig::setSpeedIconic()
+{
+    current_config.speed = iconic_config.speed;
+    current_config.acceleration = iconic_config.acceleration;
+    current_config.jerk = iconic_config.jerk;
+}
+
+double GCodePathConfig::getExtrusionMM3perMM()
 {
     return extrusion_mm3_per_mm;
 }
 
-double GCodePathConfig::getSpeed() const
+double GCodePathConfig::getSpeed()
 {
-    return speed_derivatives.speed;
+    return current_config.speed;
 }
 
-double GCodePathConfig::getAcceleration() const
+double GCodePathConfig::getAcceleration()
 {
-    return speed_derivatives.acceleration;
+    return current_config.acceleration;
 }
 
-double GCodePathConfig::getJerk() const
+double GCodePathConfig::getJerk()
 {
-    return speed_derivatives.jerk;
+    return current_config.jerk;
 }
 
-int GCodePathConfig::getLineWidth() const
+int GCodePathConfig::getLineWidth()
 {
-    return line_width;
+    return current_config.line_width;
 }
 
-bool GCodePathConfig::isTravelPath() const
+bool GCodePathConfig::isTravelPath()
 {
-    return line_width == 0;
+    return current_config.line_width == 0;
 }
 
-double GCodePathConfig::getFlowPercentage() const
+double GCodePathConfig::getFlowPercentage()
 {
-    return flow;
+    return current_config.flow;
 }
 
-double GCodePathConfig::calculateExtrusion() const
+void GCodePathConfig::calculateExtrusion()
 {
-    return INT2MM(line_width) * INT2MM(layer_thickness) * double(flow) / 100.0;
+    extrusion_mm3_per_mm = INT2MM(current_config.line_width) * INT2MM(layer_thickness) * double(current_config.flow) / 100.0;
 }
 
 

src/GCodePathConfig.h

@@ -16,70 +16,94 @@ class GCodePathConfig
     friend class GCodePlannerTest;
 public:
     /*!
-     * A simple wrapper class for all derivatives of position which are used when printing a line
+     * The path config settings which may change from layer to layer
      */
-    struct SpeedDerivatives
+    struct BasicConfig
     {
         double speed; //!< movement speed (mm/s)
         double acceleration; //!< acceleration of head movement (mm/s^2)
-        double jerk; //!< jerk of the head movement (around stand still) as instantaneous speed change (mm/s)
+        double jerk; //!< jerk of the head movement (around stand still) (mm/s^3)
+        int line_width; //!< width of the line extruded
+        double flow; //!< extrusion flow modifier in %
+        BasicConfig(); //!< basic contructor initializing with inaccurate values
+        BasicConfig(double speed, double acceleration, double jerk, int line_width, double flow); //!< basic contructor initializing all values
+        void set(double speed, double acceleration, double jerk, int line_width, double flow); //!< Set all config values
     };
-    const PrintFeatureType type; //!< name of the feature type
 private:
-    SpeedDerivatives speed_derivatives; //!< The speed settings (and acceleration and jerk) of the extruded line. May be changed when smoothSpeed is called.
-    const int line_width; //!< width of the line extruded
-    const int layer_thickness; //!< current layer height in micron
-    const double flow; //!< extrusion flow modifier in %
-    const double extrusion_mm3_per_mm;//!< current mm^3 filament moved per mm line traversed
+    BasicConfig iconic_config; //!< The basic path configuration iconic to this print feature type
+    BasicConfig current_config; //!< The current path configuration for the current layer
+    int layer_thickness; //!< current layer height in micron
+    double extrusion_mm3_per_mm;//!< current mm^3 filament moved per mm line traversed
 public:
-    GCodePathConfig(PrintFeatureType type, int line_width, int layer_height, double flow, SpeedDerivatives speed_derivatives); // , SpeedDerivatives slowdown_speed_derivatives, int layer_nr, int max_speed_layer_nr);
+    const PrintFeatureType type; //!< name of the feature type
 
     /*!
-     * copy constructor
+     * Basic constructor.
      */
-    GCodePathConfig(const GCodePathConfig& other);
+    GCodePathConfig(PrintFeatureType type);
+    
+    /*!
+     * Initialize some of the member variables.
+     * 
+     * \warning GCodePathConfig::setLayerHeight still has to be called before this object can be used.
+     * 
+     * \param speed The regular speed with which to print this feature
+     * \param line_width The line width for this feature
+     * \param flow The flow modifier to apply to the extruded filament when printing this feature
+     */
+    void init(double speed, double acceleration, double jerk, int line_width, double flow);
+
+    /*!
+     * Set the layer height and (re)compute the extrusion_per_mm
+     */
+    void setLayerHeight(int layer_height);
 
     /*!
      * Set the speed to somewhere between the speed of @p first_layer_config and the iconic speed.
      * 
      * \warning This functions should not be called with @p layer_nr > @p max_speed_layer !
      * 
-     * \warning Calling this function twice will smooth the speed more toward \p first_layer_config
-     * 
      * \param first_layer_config The speed settings at layer zero
      * \param layer_nr The layer number 
      * \param max_speed_layer The layer number for which the speed_iconic should be used.
      */
-    void smoothSpeed(SpeedDerivatives first_layer_config, int layer_nr, int max_speed_layer);
+    void smoothSpeed(BasicConfig first_layer_config, int layer_nr, double max_speed_layer);
+
+    /*!
+     * Set the speed config to the iconic speed config, i.e. the normal speed of the feature type for which this is a config.
+     * 
+     * Does the same for acceleration and jerk.
+     */
+    void setSpeedIconic();
 
     /*!
      * Can only be called after the layer height has been set (which is done while writing the gcode!)
      */
-    double getExtrusionMM3perMM() const;
+    double getExtrusionMM3perMM();
 
     /*!
      * Get the movement speed in mm/s
      */
-    double getSpeed() const;
+    double getSpeed();
 
     /*!
      * Get the current acceleration of this config
      */
-    double getAcceleration() const;
+    double getAcceleration();
 
     /*!
      * Get the current jerk of this config
      */
-    double getJerk() const;
+    double getJerk();
 
-    int getLineWidth() const;
+    int getLineWidth();
 
-    bool isTravelPath() const;
+    bool isTravelPath();
 
-    double getFlowPercentage() const;
+    double getFlowPercentage();
 
 private:
-    double calculateExtrusion() const;
+    void calculateExtrusion();
 };
 
 

src/LayerPlanBuffer.cpp

@@ -17,7 +17,7 @@ void LayerPlanBuffer::flush()
     }
     while (!buffer.empty())
     {
-        buffer.front()->writeGCode(gcode);
+        buffer.front().writeGCode(gcode);
         if (CommandSocket::isInstantiated())
         {
             CommandSocket::getInstance()->flushGcode();
@@ -324,7 +324,7 @@ void LayerPlanBuffer::insertFinalPrintTempCommand(std::vector<ExtruderPlan*>& ex
 
 void LayerPlanBuffer::insertTempCommands()
 {
-    if (buffer.back()->extruder_plans.size() == 0 || (buffer.back()->extruder_plans.size() == 1 && buffer.back()->extruder_plans[0].paths.size() == 0))
+    if (buffer.back().extruder_plans.size() == 0 || (buffer.back().extruder_plans.size() == 1 && buffer.back().extruder_plans[0].paths.size() == 0))
     { // disregard empty layer
         buffer.pop_back();
         return;
@@ -332,9 +332,9 @@ void LayerPlanBuffer::insertTempCommands()
 
     std::vector<ExtruderPlan*> extruder_plans;
     extruder_plans.reserve(buffer.size() * 2);
-    for (GCodePlanner* layer_plan : buffer)
+    for (GCodePlanner& layer_plan : buffer)
     {
-        for (ExtruderPlan& extr_plan : layer_plan->extruder_plans)
+        for (ExtruderPlan& extr_plan : layer_plan.extruder_plans)
         {
             extruder_plans.push_back(&extr_plan);
         }
@@ -342,7 +342,7 @@ void LayerPlanBuffer::insertTempCommands()
 
 
     // insert commands for all extruder plans on this layer
-    GCodePlanner& layer_plan = *buffer.back();
+    GCodePlanner& layer_plan = buffer.back();
     for (unsigned int extruder_plan_idx = 0; extruder_plan_idx < layer_plan.extruder_plans.size(); extruder_plan_idx++)
     {
         unsigned int overall_extruder_plan_idx = extruder_plans.size() - layer_plan.extruder_plans.size() + extruder_plan_idx;

src/LayerPlanBuffer.h

@@ -42,7 +42,7 @@ class LayerPlanBuffer : SettingsMessenger
 
     std::vector<bool> extruder_used_in_meshgroup; //!< For each extruder whether it has already been planned once in this meshgroup. This is used to see whether we should heat to the initial_print_temp or to the printing_temperature
 public:
-    std::list<GCodePlanner*> buffer; //!< The buffer containing several layer plans (GCodePlanner) before writing them to gcode.
+    std::list<GCodePlanner> buffer; //!< The buffer containing several layer plans (GCodePlanner) before writing them to gcode.
     
     LayerPlanBuffer(SettingsBaseVirtual* settings, GCodeExport& gcode)
     : SettingsMessenger(settings)
@@ -54,39 +54,29 @@ public:
     {
         preheat_config.setConfig(settings);
     }
-
+    
     /*!
-     * Push a new layer plan into the buffer
+     * Place a new layer plan (GcodePlanner) by constructing it with the given arguments.
+     * Pop back the oldest layer plan is it exceeds the buffer size and write it to gcode.
      */
-    void push(GCodePlanner& layer_plan)
-    {
-        buffer.push_back(&layer_plan);
-    }
-
-    /*!
-     * Process all layers in the buffer
-     * This inserts the temperature commands to start warming for a given layer in earlier layers
-     * 
-     * Pop out the earliest layer in the buffer if the buffer size is exceeded
-     * \return A nullptr or the popped gcode_layer
-     */
-    GCodePlanner* processBuffer()
+    template<typename... Args>
+    GCodePlanner& emplace_back(Args&&... constructor_args)
     {
         if (buffer.size() > 0)
         {
             insertTempCommands(); // insert preheat commands of the just completed layer plan (not the newly emplaced one)
         }
+        buffer.emplace_back(constructor_args...);
         if (buffer.size() > buffer_size)
         {
-            GCodePlanner* ret = buffer.front();
+            buffer.front().writeGCode(gcode);
             if (CommandSocket::isInstantiated())
             {
                 CommandSocket::getInstance()->flushGcode();
             }
             buffer.pop_front();
-            return ret;
         }
-        return nullptr;
+        return buffer.back();
     }
     
     /*!

src/MergeInfillLines.h

@@ -17,7 +17,7 @@ class MergeInfillLines
     std::vector<GCodePath>& paths; //!< The paths currently under consideration
     ExtruderPlan& extruder_plan; //!< The extruder plan of the paths currently under consideration
     
-    const GCodePathConfig& travelConfig; //!< The travel settings used to see whether a path is a travel path or an extrusion path
+    GCodePathConfig& travelConfig; //!< The travel settings used to see whether a path is a travel path or an extrusion path
     int64_t nozzle_size; //!< The diameter of the hole in the nozzle
     bool speed_equalize_flow_enabled; //!< Should the speed be varied with extrusion width
     double speed_equalize_flow_max; //!< Maximum speed when adjusting speed for flow
@@ -64,18 +64,9 @@ public:
     /*!
      * Simple constructor only used by MergeInfillLines::isConvertible to easily convey the environment
      */
-    MergeInfillLines(GCodeExport& gcode, int layer_nr, std::vector<GCodePath>& paths, ExtruderPlan& extruder_plan, const GCodePathConfig& travelConfig, int64_t nozzle_size, bool speed_equalize_flow_enabled, double speed_equalize_flow_max)
-    : gcode(gcode)
-    , layer_nr(layer_nr)
-    , paths(paths)
-    , extruder_plan(extruder_plan)
-    , travelConfig(travelConfig)
-    , nozzle_size(nozzle_size)
-    , speed_equalize_flow_enabled(speed_equalize_flow_enabled)
-    , speed_equalize_flow_max(speed_equalize_flow_max)
-    {
-    }
-
+    MergeInfillLines(GCodeExport& gcode, int layer_nr, std::vector<GCodePath>& paths, ExtruderPlan& extruder_plan, GCodePathConfig& travelConfig, int64_t nozzle_size, bool speed_equalize_flow_enabled, double speed_equalize_flow_max) 
+    : gcode(gcode), layer_nr(layer_nr), paths(paths), extruder_plan(extruder_plan), travelConfig(travelConfig), nozzle_size(nozzle_size), speed_equalize_flow_enabled(speed_equalize_flow_enabled), speed_equalize_flow_max(speed_equalize_flow_max) { }
+    
     /*!
      * Check for lots of small moves and combine them into one large line.
      * Updates \p path_idx to the next path which is not combined.

src/PrimeTower.cpp

@@ -15,7 +15,12 @@ namespace cura
 PrimeTower::PrimeTower(const SliceDataStorage& storage)
 : is_hollow(false)
 , wipe_from_middle(false)
+, current_pre_wipe_location_idx(0)
 {
+    for (int extruder_nr = 0; extruder_nr < MAX_EXTRUDERS; extruder_nr++)
+    {
+        last_prime_tower_poly_printed[extruder_nr] = -1;
+    }
     enabled = storage.getSettingBoolean("prime_tower_enable")
            && storage.getSettingInMicrons("prime_tower_wall_thickness") > 10
            && storage.getSettingInMicrons("prime_tower_size") > 10;
@@ -25,6 +30,34 @@ PrimeTower::PrimeTower(const SliceDataStorage& storage)
     }
 }
 
+
+
+void PrimeTower::initConfigs(const MeshGroup* meshgroup)
+{
+    extruder_count = meshgroup->getExtruderCount();
+
+    for (int extr = 0; extr < extruder_count; extr++)
+    {
+        config_per_extruder.emplace_back(PrintFeatureType::Support);// so that visualization in the old Cura still works (TODO)
+    }
+    for (int extr = 0; extr < extruder_count; extr++)
+    {
+        const ExtruderTrain* train = meshgroup->getExtruderTrain(extr);
+        config_per_extruder[extr].init(train->getSettingInMillimetersPerSecond("speed_prime_tower"), train->getSettingInMillimetersPerSecond("acceleration_prime_tower"), train->getSettingInMillimetersPerSecond("jerk_prime_tower"), train->getSettingInMicrons("prime_tower_line_width"), train->getSettingInPercentage("prime_tower_flow"));
+    }
+}
+
+void PrimeTower::setConfigs(const MeshGroup* meshgroup, const int layer_thickness)
+{
+    extruder_count = meshgroup->getExtruderCount();
+
+    for (int extr = 0; extr < extruder_count; extr++)
+    {
+        GCodePathConfig& conf = config_per_extruder[extr];
+        conf.setLayerHeight(layer_thickness);
+    }
+}
+
 void PrimeTower::generateGroundpoly(const SliceDataStorage& storage)
 {
     extruder_count = storage.meshgroup->getExtruderCount();
@@ -94,13 +127,18 @@ void PrimeTower::generatePaths_denseInfill(const SliceDataStorage& storage)
 }
 
 
-void PrimeTower::addToGcode(const SliceDataStorage& storage, GCodePlanner& gcodeLayer, const GCodeExport& gcode, const int layer_nr, const int prev_extruder, const int new_extruder) const
+void PrimeTower::addToGcode(const SliceDataStorage& storage, GCodePlanner& gcodeLayer, const GCodeExport& gcode, const int layer_nr, const int prev_extruder, const int new_extruder)
 {
     if (!enabled)
     {
         return;
     }
-    if (gcodeLayer.getPrimeTowerIsPlanned())
+    bool prime_tower_added = false;
+    for (int extruder = 0; extruder <  storage.meshgroup->getExtruderCount() && !prime_tower_added; extruder++)
+    {
+        prime_tower_added = last_prime_tower_poly_printed[extruder] == int(layer_nr);
+    }
+    if (prime_tower_added)
     { // don't print the prime tower if it has been printed already
         return;
     }
@@ -121,7 +159,7 @@ void PrimeTower::addToGcode(const SliceDataStorage& storage, GCodePlanner& gcode
     // pre-wipe:
     if (pre_wipe)
     {
-        preWipe(storage, gcodeLayer, layer_nr, new_extruder);
+        preWipe(storage, gcodeLayer, new_extruder);
     }
 
     addToGcode_denseInfill(gcodeLayer, layer_nr, new_extruder);
@@ -131,21 +169,21 @@ void PrimeTower::addToGcode(const SliceDataStorage& storage, GCodePlanner& gcode
     { //Make sure we wipe the old extruder on the prime tower.
         gcodeLayer.addTravel(post_wipe_point - gcode.getExtruderOffset(prev_extruder) + gcode.getExtruderOffset(new_extruder));
     }
-
-    gcodeLayer.setPrimeTowerIsPlanned();
 }
 
-void PrimeTower::addToGcode_denseInfill(GCodePlanner& gcode_layer, const int layer_nr, const int extruder_nr) const
+void PrimeTower::addToGcode_denseInfill(GCodePlanner& gcodeLayer, const int layer_nr, const int extruder)
 {
-    const ExtrusionMoves& pattern = patterns_per_extruder[extruder_nr][((layer_nr % 2) + 2) % 2]; // +2) %2 to handle negative layer numbers
+    ExtrusionMoves& pattern = patterns_per_extruder[extruder][((layer_nr % 2) + 2) % 2]; // +2) %2 to handle negative layer numbers
 
-    const GCodePathConfig& config = gcode_layer.configs_storage.prime_tower_config_per_extruder[extruder_nr];
+    GCodePathConfig& config = config_per_extruder[extruder];
 
-    gcode_layer.addPolygonsByOptimizer(pattern.polygons, &config);
-    gcode_layer.addLinesByOptimizer(pattern.lines, &config, SpaceFillType::Lines);
+    gcodeLayer.addPolygonsByOptimizer(pattern.polygons, &config);
+    gcodeLayer.addLinesByOptimizer(pattern.lines, &config, SpaceFillType::Lines);
+
+    last_prime_tower_poly_printed[extruder] = layer_nr;
 }
 
-Point PrimeTower::getLocationBeforePrimeTower(const SliceDataStorage& storage) const
+Point PrimeTower::getLocationBeforePrimeTower(const SliceDataStorage& storage)
 {
     Point ret(0, 0);
     int absolute_starting_points = 0;
@@ -225,10 +263,10 @@ void PrimeTower::generateWipeLocations(const SliceDataStorage& storage)
     PolygonUtils::spreadDots(segment_start, segment_end, number_of_pre_wipe_locations, pre_wipe_locations);
 }
 
-void PrimeTower::preWipe(const SliceDataStorage& storage, GCodePlanner& gcode_layer, const int layer_nr, const int extruder_nr) const
+void PrimeTower::preWipe(const SliceDataStorage& storage, GCodePlanner& gcode_layer, const int extruder_nr)
 {
-    int current_pre_wipe_location_idx = (pre_wipe_location_skip * layer_nr) % number_of_pre_wipe_locations;
     const ClosestPolygonPoint wipe_location = pre_wipe_locations[current_pre_wipe_location_idx];
+    current_pre_wipe_location_idx = (current_pre_wipe_location_idx + pre_wipe_location_skip) % number_of_pre_wipe_locations;
 
     ExtruderTrain& train = *storage.meshgroup->getExtruderTrain(extruder_nr);
     const int inward_dist = train.getSettingInMicrons("machine_nozzle_size") * 3 / 2 ;
@@ -256,7 +294,7 @@ void PrimeTower::preWipe(const SliceDataStorage& storage, GCodePlanner& gcode_la
         gcode_layer.addTravel(start);
     }
     float flow = 0.0001; // force this path being interpreted as an extrusion path, so that no Z hop will occur (TODO: really separately handle travel and extrusion moves)
-    gcode_layer.addExtrusionMove(end, &gcode_layer.configs_storage.prime_tower_config_per_extruder[extruder_nr], SpaceFillType::None, flow);
+    gcode_layer.addExtrusionMove(end, &config_per_extruder[extruder_nr], SpaceFillType::None, flow);
 }
 
 void PrimeTower::subtractFromSupport(SliceDataStorage& storage)

src/PrimeTower.h

@@ -34,6 +34,7 @@ private:
         Polygons lines;
     };
     int extruder_count; //!< number of extruders
+    std::vector<GCodePathConfig> config_per_extruder; //!< Path config for prime tower for each extruder
 
     bool is_hollow; //!< Whether the prime tower is hollow
 
@@ -46,6 +47,7 @@ private:
     const unsigned int pre_wipe_location_skip = 13; //!< How big the steps are when stepping through \ref PrimeTower::wipe_locations
     const unsigned int number_of_pre_wipe_locations = 21; //!< The required size of \ref PrimeTower::wipe_locations
     // note that the above are two consecutive numbers in the Fibonacci sequence
+    int current_pre_wipe_location_idx; //!< Index into \ref PrimeTower::wipe_locations of where to pre-wipe the nozzle
 
 public:
     bool enabled; //!< Whether the prime tower is enabled.
@@ -61,6 +63,21 @@ public:
      */
     PrimeTower(const SliceDataStorage& storage);
 
+    /*!
+     * Initialize \ref PrimeTower::config_per_extruder with speed and line width settings.
+     * 
+     * \param meshgroup Where to retrieve the setttings for each extruder
+     */
+    void initConfigs(const MeshGroup* meshgroup);
+
+    /*!
+     * Complete the \ref PrimeTower::config_per_extruder by settings the layer height.
+     * 
+     * \param meshgroup Where to retrieve the setttings for each extruder
+     * \param layer_thickness The current layer thickness
+     */
+    void setConfigs(const MeshGroup* meshgroup, const int layer_thickness);
+
     /*!
      * Generate the prime tower area to be used on each layer
      * 
@@ -87,7 +104,7 @@ public:
      * \param prev_extruder The previous extruder with which paths were planned; from which extruder a switch was made
      * \param new_extruder The switched to extruder with which the prime tower paths should be generated.
      */
-    void addToGcode(const SliceDataStorage& storage, GCodePlanner& gcode_layer, const GCodeExport& gcode, const int layer_nr, const int prev_extruder, const int new_extruder) const;
+    void addToGcode(const SliceDataStorage& storage, GCodePlanner& gcode_layer, const GCodeExport& gcode, const int layer_nr, const int prev_extruder, const int new_extruder);
 
     /*!
      * \brief Subtract the prime tower from the support areas in storage.
@@ -98,6 +115,12 @@ public:
     void subtractFromSupport(SliceDataStorage& storage);
 
 private:
+    /*!
+     * Layer number of the last layer in which a prime tower has been printed per extruder train.  
+     * 
+     * This is recorded per extruder to account for a prime tower per extruder, instead of the mixed prime tower.
+     */
+    int last_prime_tower_poly_printed[MAX_EXTRUDERS];
 
     /*!
      * Find an approriate representation for the point representing the location before going to the prime tower
@@ -107,7 +130,7 @@ private:
      * \param storage where to get settings from
      * \return that location
      */
-    Point getLocationBeforePrimeTower(const SliceDataStorage& storage) const;
+    Point getLocationBeforePrimeTower(const SliceDataStorage& storage);
 
     /*!
      * \param storage where to get settings from
@@ -136,17 +159,16 @@ private:
      * \param extruder The extruder we just switched to, with which the prime
      * tower paths should be drawn.
      */
-    void addToGcode_denseInfill(GCodePlanner& gcode_layer, const int layer_nr, const int extruder) const;
+    void addToGcode_denseInfill(GCodePlanner& gcode_layer, const int layer_nr, const int extruder);
 
     /*!
      * Plan the moves for wiping the current nozzles oozed material before starting to print the prime tower.
      * 
      * \param storage where to get settings from
      * \param[out] gcode_layer where to add the planned paths for wiping
-     * \param layer_nr The layer number of the \p gcode_layer
      * \param extruder_nr The current extruder
      */
-    void preWipe(const SliceDataStorage& storage, GCodePlanner& gcode_layer, const int layer_nr, const int extruder_nr) const;
+    void preWipe(const SliceDataStorage& storage, GCodePlanner& gcode_layer, const int extruder_nr);
 };
 
 

src/WallsComputation.cpp

@@ -12,12 +12,6 @@ WallsComputation::WallsComputation(int wall_0_inset, int line_width_0, int line_
 {
 }
 
-/*
- * This function is executed in a parallel region based on layer_nr.
- * When modifying make sure any changes does not introduce data races.
- *
- * generateInsets only reads and writes data for the current layer
- */
 void WallsComputation::generateInsets(SliceLayerPart* part)
 {
     if (insetCount == 0)
@@ -64,12 +58,6 @@ void WallsComputation::generateInsets(SliceLayerPart* part)
     }
 }
 
-/*
- * This function is executed in a parallel region based on layer_nr.
- * When modifying make sure any changes does not introduce data races.
- *
- * generateInsets only reads and writes data for the current layer
- */
 void WallsComputation::generateInsets(SliceLayer* layer)
 {
     for(unsigned int partNr = 0; partNr < layer->parts.size(); partNr++)

src/Weaver.cpp

@@ -389,7 +389,7 @@ void Weaver::chainify_polygons(Polygons& parts1, Point start_close_to, Polygons&
 {
     for (unsigned int prt = 0 ; prt < parts1.size(); prt++)
     {
-        ConstPolygonRef upperPart = parts1[prt];
+        const PolygonRef upperPart = parts1[prt];
         
         ClosestPolygonPoint closestInPoly = PolygonUtils::findClosest(start_close_to, upperPart);
 
@@ -439,7 +439,7 @@ void Weaver::connect_polygons(Polygons& supporting, int z0, Polygons& supported,
     for (unsigned int prt = 0 ; prt < supported.size(); prt++)
     {
         
-        ConstPolygonRef upperPart(supported[prt]);
+        const PolygonRef upperPart = supported[prt];
         
         
         parts.emplace_back(prt);

src/bridge.cpp

@@ -5,7 +5,7 @@
 
 namespace cura {
 
-int bridgeAngle(Polygons outline, const SliceLayer* prevLayer)
+int bridgeAngle(Polygons outline, SliceLayer* prevLayer)
 {
     AABB boundaryBox(outline);
     //To detect if we have a bridge, first calculate the intersection of the current layer with the previous layer.

src/bridge.h

@@ -6,7 +6,7 @@ namespace cura {
     class Polygons;
     class SliceLayer;
 
-int bridgeAngle(Polygons outline, const SliceLayer* prevLayer);
+int bridgeAngle(Polygons outline, SliceLayer* prevLayer);
 
 }//namespace cura
 

src/commandSocket.cpp

@@ -215,7 +215,7 @@ public:
     /*!
      * Adds closed polygon to the current path
      */
-    void sendPolygon(PrintFeatureType print_feature_type, ConstPolygonRef poly, int width);
+    void sendPolygon(PrintFeatureType print_feature_type, Polygon poly, int width);
 private:
     /*!
      * Convert and add a point to the points buffer, each point being represented as two consecutive floats. All members adding a 2D point to the data should use this function.
@@ -522,7 +522,7 @@ void CommandSocket::sendPolygons(PrintFeatureType type, const Polygons& polygons
 #endif
 }
 
-void CommandSocket::sendPolygon(PrintFeatureType type, ConstPolygonRef polygon, int line_width)
+void CommandSocket::sendPolygon(PrintFeatureType type, Polygon& polygon, int line_width)
 {
 #ifdef ARCUS
     if (CommandSocket::isInstantiated())
@@ -799,7 +799,7 @@ void CommandSocket::PathCompiler::sendLineTo(PrintFeatureType print_feature_type
     }
 }
 
-void CommandSocket::PathCompiler::sendPolygon(PrintFeatureType print_feature_type, ConstPolygonRef polygon, int width)
+void CommandSocket::PathCompiler::sendPolygon(PrintFeatureType print_feature_type, Polygon polygon, int width)
 {
     if (polygon.size() < 2)
     {

src/commandSocket.h

@@ -64,7 +64,7 @@ public:
     /*! 
      * Send a polygon to the front-end. This is used for the layerview in the GUI
      */
-    static void sendPolygon(cura::PrintFeatureType type, ConstPolygonRef polygon, int line_width);
+    static void sendPolygon(cura::PrintFeatureType type, Polygon& polygon, int line_width);
 
     /*!
      * Send a line to the front-end. This is used for the layerview in the GUI

src/gcodeExport.cpp

@@ -270,7 +270,7 @@ void GCodeExport::setFlavor(EGCodeFlavor flavor)
     }
 }
 
-EGCodeFlavor GCodeExport::getFlavor() const
+EGCodeFlavor GCodeExport::getFlavor()
 {
     return this->flavor;
 }
@@ -775,7 +775,7 @@ void GCodeExport::switchExtruder(int new_extruder, const RetractionConfig& retra
 
     bool force = true;
     bool extruder_switch = true;
-    writeRetraction(retraction_config_old_extruder, force, extruder_switch);
+    writeRetraction(const_cast<RetractionConfig&>(retraction_config_old_extruder), force, extruder_switch);
 
     resetExtrusionValue(); // zero the E value on the old extruder, so that the current_e_value is registered on the old extruder
 

src/gcodeExport.h

@@ -188,7 +188,7 @@ public:
     Point getGcodePos(const int64_t x, const int64_t y, const int extruder_train) const;
     
     void setFlavor(EGCodeFlavor flavor);
-    EGCodeFlavor getFlavor() const;
+    EGCodeFlavor getFlavor();
     
     void setZ(int z);
     

src/gcodePlanner.cpp

@@ -10,7 +10,7 @@
 namespace cura {
 
 
-ExtruderPlan::ExtruderPlan(int extruder, Point start_position, int layer_nr, bool is_initial_layer, int layer_thickness, const FanSpeedLayerTimeSettings& fan_speed_layer_time_settings, const RetractionConfig& retraction_config)
+ExtruderPlan::ExtruderPlan(int extruder, Point start_position, int layer_nr, bool is_initial_layer, int layer_thickness, FanSpeedLayerTimeSettings& fan_speed_layer_time_settings, const RetractionConfig& retraction_config)
 : extruder(extruder)
 , heated_pre_travel_time(0)
 , initial_printing_temperature(-1)
@@ -56,7 +56,7 @@ double ExtruderPlan::getFanSpeed()
 }
 
 
-GCodePath* GCodePlanner::getLatestPathWithConfig(const GCodePathConfig* config, SpaceFillType space_fill_type, float flow, bool spiralize)
+GCodePath* GCodePlanner::getLatestPathWithConfig(GCodePathConfig* config, SpaceFillType space_fill_type, float flow, bool spiralize)
 {
     std::vector<GCodePath>& paths = extruder_plans.back().paths;
     if (paths.size() > 0 && paths.back().config == config && !paths.back().done && paths.back().flow == flow) // spiralize can only change when a travel path is in between
@@ -81,26 +81,23 @@ void GCodePlanner::forceNewPathStart()
         paths[paths.size()-1].done = true;
 }
 
-GCodePlanner::GCodePlanner(const SliceDataStorage& storage, int layer_nr, int z, int layer_thickness, PlanningState last_planned_state, const std::vector<FanSpeedLayerTimeSettings>& fan_speed_layer_time_settings_per_extruder, CombingMode combing_mode, int64_t comb_boundary_offset, bool travel_avoid_other_parts, int64_t travel_avoid_distance)
+GCodePlanner::GCodePlanner(SliceDataStorage& storage, int layer_nr, int z, int layer_thickness, Point last_position, int current_extruder, bool is_inside_mesh, std::vector<FanSpeedLayerTimeSettings>& fan_speed_layer_time_settings_per_extruder, CombingMode combing_mode, int64_t comb_boundary_offset, bool travel_avoid_other_parts, int64_t travel_avoid_distance)
 : storage(storage)
-, configs_storage(storage, layer_nr, layer_thickness)
 , layer_nr(layer_nr)
 , is_initial_layer(layer_nr == 0 - Raft::getTotalExtraLayers(storage))
 , z(z)
 , layer_thickness(layer_thickness)
-, start_position(last_planned_state.last_position)
-, lastPosition(last_planned_state.last_position)
-, has_prime_tower_planned(false)
-, last_extruder_previous_layer(last_planned_state.current_extruder)
-, last_planned_extruder_setting_base(storage.meshgroup->getExtruderTrain(last_planned_state.current_extruder))
+, start_position(last_position)
+, lastPosition(last_position)
+, last_extruder_previous_layer(current_extruder)
+, last_planned_extruder_setting_base(storage.meshgroup->getExtruderTrain(current_extruder))
 , comb_boundary_inside(computeCombBoundaryInside(combing_mode))
 , fan_speed_layer_time_settings_per_extruder(fan_speed_layer_time_settings_per_extruder)
 {
-    int current_extruder = last_planned_state.current_extruder;
     extruder_plans.reserve(storage.meshgroup->getExtruderCount());
     extruder_plans.emplace_back(current_extruder, start_position, layer_nr, is_initial_layer, layer_thickness, fan_speed_layer_time_settings_per_extruder[current_extruder], storage.retraction_config_per_extruder[current_extruder]);
     comb = nullptr;
-    was_inside = last_planned_state.is_inside_mesh_layer_part;
+    was_inside = is_inside_mesh; 
     is_inside = false; // assumes the next move will not be to inside a layer part (overwritten just before going into a layer part)
     if (combing_mode != CombingMode::OFF)
     {
@@ -142,12 +139,12 @@ Polygons GCodePlanner::computeCombBoundaryInside(CombingMode combing_mode)
     else 
     {
         Polygons comb_boundary;
-        for (const SliceMeshStorage& mesh : storage.meshes)
+        for (SliceMeshStorage& mesh : storage.meshes)
         {
-            const SliceLayer& layer = mesh.layers[layer_nr];
+            SliceLayer& layer = mesh.layers[layer_nr];
             if (mesh.getSettingAsCombingMode("retraction_combing") == CombingMode::NO_SKIN)
             {
-                for (const SliceLayerPart& part : layer.parts)
+                for (SliceLayerPart& part : layer.parts)
                 {
                     comb_boundary.add(part.infill_area);
                 }
@@ -244,12 +241,12 @@ void GCodePlanner::moveInsideCombBoundary(int distance)
 GCodePath& GCodePlanner::addTravel(Point p)
 {
     GCodePath* path = nullptr;
-    const GCodePathConfig& travel_config = configs_storage.travel_config_per_extruder[getExtruder()];
-    const RetractionConfig& retraction_config = storage.retraction_config_per_extruder[getExtruder()];
+    GCodePathConfig& travel_config = storage.travel_config_per_extruder[getExtruder()];
+    RetractionConfig& retraction_config = storage.retraction_config_per_extruder[getExtruder()];
     
     bool combed = false;
 
-    const SettingsBaseVirtual* extr = getLastPlannedExtruderTrainSettings();
+    SettingsBaseVirtual* extr = getLastPlannedExtruderTrainSettings();
 
     const bool perform_z_hops = extr->getSettingBoolean("retraction_hop_enabled");
 
@@ -336,7 +333,7 @@ GCodePath& GCodePlanner::addTravel_simple(Point p, GCodePath* path)
 {
     if (path == nullptr)
     {
-        path = getLatestPathWithConfig(&configs_storage.travel_config_per_extruder[getExtruder()], SpaceFillType::None);
+        path = getLatestPathWithConfig(&storage.travel_config_per_extruder[getExtruder()], SpaceFillType::None);
     }
     path->points.push_back(p);
     lastPosition = p;
@@ -352,27 +349,27 @@ void GCodePlanner::planPrime()
     forceNewPathStart();
 }
 
-void GCodePlanner::addExtrusionMove(Point p, const GCodePathConfig* config, SpaceFillType space_fill_type, float flow, bool spiralize)
+void GCodePlanner::addExtrusionMove(Point p, GCodePathConfig* config, SpaceFillType space_fill_type, float flow, bool spiralize)
 {
     getLatestPathWithConfig(config, space_fill_type, flow, spiralize)->points.push_back(p);
     lastPosition = p;
 }
 
-void GCodePlanner::addPolygon(ConstPolygonRef polygon, int start_idx, const GCodePathConfig* config, WallOverlapComputation* wall_overlap_computation, coord_t wall_0_wipe_dist, bool spiralize)
+void GCodePlanner::addPolygon(PolygonRef polygon, int start_idx, GCodePathConfig* config, WallOverlapComputation* wall_overlap_computation, coord_t wall_0_wipe_dist, bool spiralize, float flow_ratio)
 {
     Point p0 = polygon[start_idx];
     addTravel(p0);
     for (unsigned int point_idx = 1; point_idx < polygon.size(); point_idx++)
     {
         Point p1 = polygon[(start_idx + point_idx) % polygon.size()];
-        float flow = (wall_overlap_computation)? wall_overlap_computation->getFlow(p0, p1) : 1.0;
+        float flow = (wall_overlap_computation)? flow_ratio * wall_overlap_computation->getFlow(p0, p1) : flow_ratio;
         addExtrusionMove(p1, config, SpaceFillType::Polygons, flow, spiralize);
         p0 = p1;
     }
     if (polygon.size() > 2)
     {
-        const Point& p1 = polygon[start_idx];
-        float flow = (wall_overlap_computation)? wall_overlap_computation->getFlow(p0, p1) : 1.0;
+        Point& p1 = polygon[start_idx];
+        float flow = (wall_overlap_computation)? flow_ratio * wall_overlap_computation->getFlow(p0, p1) : flow_ratio;
         addExtrusionMove(p1, config, SpaceFillType::Polygons, flow, spiralize);
 
         if (wall_0_wipe_dist > 0)
@@ -406,7 +403,7 @@ void GCodePlanner::addPolygon(ConstPolygonRef polygon, int start_idx, const GCod
     }
 }
 
-void GCodePlanner::addPolygonsByOptimizer(const Polygons& polygons, const GCodePathConfig* config, WallOverlapComputation* wall_overlap_computation, EZSeamType z_seam_type, Point z_seam_pos, coord_t wall_0_wipe_dist, bool spiralize)
+void GCodePlanner::addPolygonsByOptimizer(Polygons& polygons, GCodePathConfig* config, WallOverlapComputation* wall_overlap_computation, EZSeamType z_seam_type, Point z_seam_pos, coord_t wall_0_wipe_dist, bool spiralize, float flow_ratio)
 {
     if (polygons.size() == 0)
     {
@@ -420,10 +417,10 @@ void GCodePlanner::addPolygonsByOptimizer(const Polygons& polygons, const GCodeP
     orderOptimizer.optimize();
     for (unsigned int poly_idx : orderOptimizer.polyOrder)
     {
-        addPolygon(polygons[poly_idx], orderOptimizer.polyStart[poly_idx], config, wall_overlap_computation, wall_0_wipe_dist, spiralize);
+        addPolygon(polygons[poly_idx], orderOptimizer.polyStart[poly_idx], config, wall_overlap_computation, wall_0_wipe_dist, spiralize, flow_ratio);
     }
 }
-void GCodePlanner::addLinesByOptimizer(const Polygons& polygons, const GCodePathConfig* config, SpaceFillType space_fill_type, int wipe_dist)
+void GCodePlanner::addLinesByOptimizer(Polygons& polygons, GCodePathConfig* config, SpaceFillType space_fill_type, int wipe_dist, float flow_ratio)
 {
     LineOrderOptimizer orderOptimizer(lastPosition);
     for (unsigned int line_idx = 0; line_idx < polygons.size(); line_idx++)
@@ -433,13 +430,13 @@ void GCodePlanner::addLinesByOptimizer(const Polygons& polygons, const GCodePath
     orderOptimizer.optimize();
     for (int poly_idx : orderOptimizer.polyOrder)
     {
-        ConstPolygonRef polygon = polygons[poly_idx];
+        PolygonRef polygon = polygons[poly_idx];
         int start = orderOptimizer.polyStart[poly_idx];
         int end = 1 - start;
-        const Point& p0 = polygon[start];
+        Point& p0 = polygon[start];
         addTravel(p0);
-        const Point& p1 = polygon[end];
-        addExtrusionMove(p1, config, space_fill_type);
+        Point& p1 = polygon[end];
+        addExtrusionMove(p1, config, space_fill_type, flow_ratio);
         if (wipe_dist != 0)
         {
             int line_width = config->getLineWidth();
@@ -556,7 +553,7 @@ TimeMaterialEstimates ExtruderPlan::computeNaiveTimeEstimates()
 
 void ExtruderPlan::processFanSpeedAndMinimalLayerTime(bool force_minimal_layer_time)
 {
-    const FanSpeedLayerTimeSettings& fsml = fan_speed_layer_time_settings;
+    FanSpeedLayerTimeSettings& fsml = fan_speed_layer_time_settings;
     TimeMaterialEstimates estimates = computeNaiveTimeEstimates();
     totalPrintTime = estimates.getTotalTime();
     if (force_minimal_layer_time)
@@ -639,6 +636,8 @@ void GCodePlanner::processFanSpeedAndMinimalLayerTime()
 
 void GCodePlanner::writeGCode(GCodeExport& gcode)
 {
+    completeConfigs();
+    
     CommandSocket::setLayerForSend(layer_nr);
     CommandSocket::setSendCurrentPosition( gcode.getPositionXY() );
     gcode.setLayerNr(layer_nr);
@@ -654,7 +653,7 @@ void GCodePlanner::writeGCode(GCodeExport& gcode)
     gcode.setZ(z);
     
     
-    const GCodePathConfig* last_extrusion_config = nullptr; // used to check whether we need to insert a TYPE comment in the gcode.
+    GCodePathConfig* last_extrusion_config = nullptr; // used to check whether we need to insert a TYPE comment in the gcode.
 
     int extruder = gcode.getExtruderNr();
     bool acceleration_enabled = storage.getSettingBoolean("acceleration_enabled");
@@ -663,7 +662,7 @@ void GCodePlanner::writeGCode(GCodeExport& gcode)
     for(unsigned int extruder_plan_idx = 0; extruder_plan_idx < extruder_plans.size(); extruder_plan_idx++)
     {
         ExtruderPlan& extruder_plan = extruder_plans[extruder_plan_idx];
-        const RetractionConfig& retraction_config = storage.retraction_config_per_extruder[extruder_plan.extruder];
+        RetractionConfig& retraction_config = storage.retraction_config_per_extruder[extruder_plan.extruder];
 
         if (extruder != extruder_plan.extruder)
         {
@@ -765,7 +764,7 @@ void GCodePlanner::writeGCode(GCodeExport& gcode)
             else
                 speed *= extruder_plan.getExtrudeSpeedFactor();
 
-            if (MergeInfillLines(gcode, layer_nr, paths, extruder_plan, configs_storage.travel_config_per_extruder[extruder], nozzle_size, speed_equalize_flow_enabled, speed_equalize_flow_max).mergeInfillLines(path_idx)) // !! has effect on path_idx !!
+            if (MergeInfillLines(gcode, layer_nr, paths, extruder_plan, storage.travel_config_per_extruder[extruder], nozzle_size, speed_equalize_flow_enabled, speed_equalize_flow_max).mergeInfillLines(path_idx)) // !! has effect on path_idx !!
             { // !! has effect on path_idx !!
                 // works when path_idx is the index of the travel move BEFORE the infill lines to be merged
                 continue;
@@ -788,7 +787,7 @@ void GCodePlanner::writeGCode(GCodeExport& gcode)
             bool spiralize = path.spiralize;
             if (!spiralize) // normal (extrusion) move (with coasting
             {
-                const CoastingConfig& coasting_config = storage.coasting_config[extruder];
+                CoastingConfig& coasting_config = storage.coasting_config[extruder];
                 bool coasting = coasting_config.coasting_enable; 
                 if (coasting)
                 {
@@ -859,15 +858,15 @@ void GCodePlanner::writeGCode(GCodeExport& gcode)
         if (train->getSettingBoolean("cool_lift_head") && extruder_plan.extraTime > 0.0)
         {
             gcode.writeComment("Small layer, adding delay");
-            const RetractionConfig& retraction_config = storage.retraction_config_per_extruder[gcode.getExtruderNr()];
+            RetractionConfig& retraction_config = storage.retraction_config_per_extruder[gcode.getExtruderNr()];
             gcode.writeRetraction(retraction_config);
             if (extruder_plan_idx == extruder_plans.size() - 1 || !train->getSettingBoolean("machine_extruder_end_pos_abs"))
             { // only move the head if it's the last extruder plan; otherwise it's already at the switching bay area 
                 // or do it anyway when we switch extruder in-place
                 gcode.setZ(gcode.getPositionZ() + MM2INT(3.0));
-                gcode.writeMove(gcode.getPositionXY(), configs_storage.travel_config_per_extruder[extruder].getSpeed(), 0);
+                gcode.writeMove(gcode.getPositionXY(), storage.travel_config_per_extruder[extruder].getSpeed(), 0);
                 // TODO: is this safe?! wouldn't the head move into the sides then?!
-                gcode.writeMove(gcode.getPositionXY() - Point(-MM2INT(20.0), 0), configs_storage.travel_config_per_extruder[extruder].getSpeed(), 0);
+                gcode.writeMove(gcode.getPositionXY() - Point(-MM2INT(20.0), 0), storage.travel_config_per_extruder[extruder].getSpeed(), 0);
             }
             gcode.writeDelay(extruder_plan.extraTime);
         }
@@ -887,6 +886,109 @@ void GCodePlanner::overrideFanSpeeds(double speed)
 }
 
 
+void GCodePlanner::completeConfigs()
+{
+    storage.support_config.setLayerHeight(layer_thickness);
+    storage.support_skin_config.setLayerHeight(layer_thickness);
+    
+    for (SliceMeshStorage& mesh : storage.meshes)
+    {
+        mesh.inset0_config.setLayerHeight(layer_thickness);
+
+        mesh.insetX_config.setLayerHeight(layer_thickness);
+        mesh.skin_config.setLayerHeight(layer_thickness);
+        mesh.perimeter_gap_config.setLayerHeight(layer_thickness);
+        for(unsigned int idx=0; idx<MAX_INFILL_COMBINE; idx++)
+        {
+            mesh.infill_config[idx].setLayerHeight(layer_thickness);
+        }
+    }
+    
+    storage.primeTower.setConfigs(storage.meshgroup, layer_thickness);
+    
+    processInitialLayersSpeedup();
+}
+
+
+void GCodePlanner::processInitialLayersSpeedup()
+{
+    int initial_speedup_layers = storage.getSettingAsCount("speed_slowdown_layers");
+    if (layer_nr >= 0 && layer_nr < initial_speedup_layers)
+    {
+        GCodePathConfig::BasicConfig initial_layer_speed_config;
+        int extruder_nr_support_infill = storage.getSettingAsIndex((layer_nr == 0)? "support_extruder_nr_layer_0" : "support_infill_extruder_nr");
+        initial_layer_speed_config.speed = storage.meshgroup->getExtruderTrain(extruder_nr_support_infill)->getSettingInMillimetersPerSecond("speed_print_layer_0");
+        initial_layer_speed_config.acceleration = storage.meshgroup->getExtruderTrain(extruder_nr_support_infill)->getSettingInMillimetersPerSecond("acceleration_print_layer_0");
+        initial_layer_speed_config.jerk = storage.meshgroup->getExtruderTrain(extruder_nr_support_infill)->getSettingInMillimetersPerSecond("jerk_print_layer_0");
+
+        //Support (global).
+        storage.support_config.smoothSpeed(initial_layer_speed_config, layer_nr, initial_speedup_layers);
+
+        //Support roof (global).
+        int extruder_nr_support_skin = storage.getSettingAsIndex("support_interface_extruder_nr");
+        initial_layer_speed_config.speed = storage.meshgroup->getExtruderTrain(extruder_nr_support_skin)->getSettingInMillimetersPerSecond("speed_print_layer_0");
+        initial_layer_speed_config.acceleration = storage.meshgroup->getExtruderTrain(extruder_nr_support_skin)->getSettingInMillimetersPerSecond("acceleration_print_layer_0");
+        initial_layer_speed_config.jerk = storage.meshgroup->getExtruderTrain(extruder_nr_support_skin)->getSettingInMillimetersPerSecond("jerk_print_layer_0");
+        storage.support_skin_config.smoothSpeed(initial_layer_speed_config, layer_nr, initial_speedup_layers);
+
+        for (int extruder_nr = 0; extruder_nr < storage.meshgroup->getExtruderCount(); ++extruder_nr)
+        {
+            const ExtruderTrain* extruder_train = storage.meshgroup->getExtruderTrain(extruder_nr);
+            initial_layer_speed_config.speed = extruder_train->getSettingInMillimetersPerSecond("speed_travel_layer_0");
+            initial_layer_speed_config.acceleration = extruder_train->getSettingInMillimetersPerSecond("acceleration_travel_layer_0");
+            initial_layer_speed_config.jerk = extruder_train->getSettingInMillimetersPerSecond("jerk_travel_layer_0");
+
+            //Travel speed (per extruder).
+            storage.travel_config_per_extruder[extruder_nr].smoothSpeed(initial_layer_speed_config, layer_nr, initial_speedup_layers);
+        }
+
+        for (SliceMeshStorage& mesh : storage.meshes)
+        {
+            initial_layer_speed_config.speed = mesh.getSettingInMillimetersPerSecond("speed_print_layer_0");
+            initial_layer_speed_config.acceleration = mesh.getSettingInMillimetersPerSecond("acceleration_print_layer_0");
+            initial_layer_speed_config.jerk = mesh.getSettingInMillimetersPerSecond("jerk_print_layer_0");
+
+            //Outer wall speed (per mesh).
+            mesh.inset0_config.smoothSpeed(initial_layer_speed_config, layer_nr, initial_speedup_layers);
+
+            //Inner wall speed (per mesh).
+            mesh.insetX_config.smoothSpeed(initial_layer_speed_config, layer_nr, initial_speedup_layers);
+
+            //Skin speed (per mesh).
+            mesh.skin_config.smoothSpeed(initial_layer_speed_config, layer_nr, initial_speedup_layers);
+            mesh.perimeter_gap_config.smoothSpeed(initial_layer_speed_config, layer_nr, initial_speedup_layers);
+
+            for (unsigned int idx = 0; idx < MAX_INFILL_COMBINE; idx++)
+            {
+                //Infill speed (per combine part per mesh).
+                mesh.infill_config[idx].smoothSpeed(initial_layer_speed_config, layer_nr, initial_speedup_layers);
+            }
+        }
+    }
+    else if (layer_nr == initial_speedup_layers) //At the topmost layer of the gradient, reset all speeds to the typical speeds.
+    {
+        storage.support_config.setSpeedIconic();
+        storage.support_skin_config.setSpeedIconic();
+        for (int extruder_nr = 0; extruder_nr < storage.meshgroup->getExtruderCount(); ++extruder_nr)
+        {
+            storage.travel_config_per_extruder[extruder_nr].setSpeedIconic();
+        }
+        for (SliceMeshStorage& mesh : storage.meshes)
+        {
+            mesh.inset0_config.setSpeedIconic();
+            mesh.insetX_config.setSpeedIconic();
+            mesh.skin_config.setSpeedIconic();
+            mesh.perimeter_gap_config.setSpeedIconic();
+            for (unsigned int idx = 0; idx < MAX_INFILL_COMBINE; idx++)
+            {
+                mesh.infill_config[idx].setSpeedIconic();
+            }
+        }
+    }
+}
+
+
+
 bool GCodePlanner::makeRetractSwitchRetract(GCodeExport& gcode, unsigned int extruder_plan_idx, unsigned int path_idx)
 {
     std::vector<GCodePath>& paths = extruder_plans[extruder_plan_idx].paths;

src/gcodePlanner.h

@@ -16,7 +16,6 @@
 #include "FanSpeedLayerTime.h"
 #include "SpaceFillType.h"
 #include "GCodePathConfig.h"
-#include "settings/PathConfigStorage.h"
 
 #include "utils/optional.h"
 
@@ -58,7 +57,7 @@ public:
      * \param extruder The extruder number for which this object is a plan.
      * \param start_position The position the head is when this extruder plan starts
      */
-    ExtruderPlan(int extruder, Point start_position, int layer_nr, bool is_initial_layer, int layer_thickness, const FanSpeedLayerTimeSettings& fan_speed_layer_time_settings, const RetractionConfig& retraction_config);
+    ExtruderPlan(int extruder, Point start_position, int layer_nr, bool is_initial_layer, int layer_thickness, FanSpeedLayerTimeSettings& fan_speed_layer_time_settings, const RetractionConfig& retraction_config);
 
     /*!
      * Add a new Insert, constructed with the given arguments
@@ -166,7 +165,7 @@ protected:
 
     int layer_thickness; //!< The thickness of this layer in Z-direction
 
-    const FanSpeedLayerTimeSettings& fan_speed_layer_time_settings; //!< The fan speed and layer time settings used to limit this extruder plan
+    FanSpeedLayerTimeSettings& fan_speed_layer_time_settings; //!< The fan speed and layer time settings used to limit this extruder plan
 
     const RetractionConfig& retraction_config; //!< The retraction settings for the extruder of this plan
 
@@ -216,25 +215,9 @@ class GCodePlanner : public NoCopy
 {
     friend class LayerPlanBuffer;
     friend class GCodePlannerTest;
-public:
-    /*!
-     * The state which is passed along between layer plans.
-     * This is what a \ref GCodePlanner delivers to further computation in \ref FffGcodeWriter
-     * This is the state which is currently planned, not which is written to gcode.
-     */
-    struct PlanningState
-    {
-        Point last_position; //!< The position of the head before planning the next layer
-        int current_extruder; //!< The extruder train in use before planning the next layer
-        bool is_inside_mesh_layer_part; //!< Whether the last position was inside a layer part (used in combing)
-    };
 private:
-    const SliceDataStorage& storage; //!< The polygon data obtained from FffPolygonProcessor
+    SliceDataStorage& storage; //!< The polygon data obtained from FffPolygonProcessor
 
-public:
-    const PathConfigStorage configs_storage; //!< The line configs for this layer for each feature type
-
-private:
     int layer_nr; //!< The layer number of this layer plan
     int is_initial_layer; //!< Whether this is the first layer (which might be raft)
     
@@ -244,9 +227,7 @@ private:
     
     Point start_position;
     Point lastPosition;
-
-    bool has_prime_tower_planned;
-
+    
     std::vector<ExtruderPlan> extruder_plans; //!< should always contain at least one ExtruderPlan
 
     int last_extruder_previous_layer; //!< The last id of the extruder with which was printed in the previous layer
@@ -257,7 +238,7 @@ private:
     Comb* comb;
 
 
-    const std::vector<FanSpeedLayerTimeSettings>& fan_speed_layer_time_settings_per_extruder;
+    std::vector<FanSpeedLayerTimeSettings>& fan_speed_layer_time_settings_per_extruder;
     
 private:
     /*!
@@ -270,7 +251,7 @@ private:
      * \param spiralize Whether to gradually increase the z while printing. (Note that this path may be part of a sequence of spiralized paths, forming one polygon)
      * \return A path with the given config which is now the last path in GCodePlanner::paths
      */
-    GCodePath* getLatestPathWithConfig(const GCodePathConfig* config, SpaceFillType space_fill_type, float flow = 1.0, bool spiralize = false);
+    GCodePath* getLatestPathWithConfig(GCodePathConfig* config, SpaceFillType space_fill_type, float flow = 1.0, bool spiralize = false);
 
 public:
     /*!
@@ -293,7 +274,7 @@ public:
      * \param last_position The position of the head at the start of this gcode layer
      * \param combing_mode Whether combing is enabled and full or within infill only.
      */
-    GCodePlanner(const SliceDataStorage& storage, int layer_nr, int z, int layer_height, PlanningState last_planned_state, const std::vector<FanSpeedLayerTimeSettings>& fan_speed_layer_time_settings_per_extruder, CombingMode combing_mode, int64_t comb_boundary_offset, bool travel_avoid_other_parts, int64_t travel_avoid_distance);
+    GCodePlanner(SliceDataStorage& storage, int layer_nr, int z, int layer_height, Point last_position, int current_extruder, bool is_inside_mesh, std::vector<FanSpeedLayerTimeSettings>& fan_speed_layer_time_settings_per_extruder, CombingMode combing_mode, int64_t comb_boundary_offset, bool travel_avoid_other_parts, int64_t travel_avoid_distance);
     ~GCodePlanner();
 
     void overrideFanSpeeds(double speed);
@@ -311,21 +292,12 @@ private:
     Polygons computeCombBoundaryInside(CombingMode combing_mode);
 
 public:
-    int getLayerNr() const
+    int getLayerNr()
     {
         return layer_nr;
     }
-
-    PlanningState getPlanningState() const
-    {
-        PlanningState ret;
-        ret.last_position = lastPosition;
-        ret.current_extruder = getExtruder();
-        ret.is_inside_mesh_layer_part = was_inside;
-        return ret;
-    }
-
-    Point getLastPosition() const
+    
+    Point getLastPosition()
     {
         return lastPosition;
     }
@@ -333,25 +305,14 @@ public:
     /*!
      * return whether the last position planned was inside the mesh (used in combing)
      */
-    bool getIsInsideMesh() const
+    bool getIsInsideMesh()
     {
         return was_inside;
     }
-
-    bool getPrimeTowerIsPlanned() const
-    {
-        return has_prime_tower_planned;
-    }
-
-    void setPrimeTowerIsPlanned()
-    {
-        has_prime_tower_planned = true;
-    }
-
     /*!
      * send a line segment through the command socket from the previous point to the given point \p to
      */
-    void sendLineTo(PrintFeatureType print_feature_type, Point to, int line_width) const
+    void sendLineTo(PrintFeatureType print_feature_type, Point to, int line_width)
     {
         CommandSocket::sendLineTo(print_feature_type, to, line_width);
     }
@@ -375,7 +336,7 @@ public:
     /*!
      * Get the last planned extruder.
      */
-    int getExtruder() const
+    int getExtruder()
     {
         return extruder_plans.back().extruder;
     }
@@ -416,7 +377,7 @@ public:
      * \param flow A modifier of the extrusion width which would follow from the \p config
      * \param spiralize Whether to gradually increase the z while printing. (Note that this path may be part of a sequence of spiralized paths, forming one polygon)
      */
-    void addExtrusionMove(Point p, const GCodePathConfig* config, SpaceFillType space_fill_type, float flow = 1.0, bool spiralize = false);
+    void addExtrusionMove(Point p, GCodePathConfig* config, SpaceFillType space_fill_type, float flow = 1.0, bool spiralize = false);
 
     /*!
      * Add polygon to the gcode starting at vertex \p startIdx
@@ -426,8 +387,9 @@ public:
      * \param wall_overlap_computation The wall overlap compensation calculator for each given segment (optionally nullptr)
      * \param wall_0_wipe_dist The distance to travel along the polygon after it has been laid down, in order to wipe the start and end of the wall together
      * \param spiralize Whether to gradually increase the z height from the normal layer height to the height of the next layer over this polygon
+     * \param flow_ratio The ratio with which to multiply the extrusion amount
      */
-    void addPolygon(ConstPolygonRef polygon, int startIdx, const GCodePathConfig* config, WallOverlapComputation* wall_overlap_computation = nullptr, coord_t wall_0_wipe_dist = 0, bool spiralize = false);
+    void addPolygon(PolygonRef polygon, int startIdx, GCodePathConfig* config, WallOverlapComputation* wall_overlap_computation = nullptr, coord_t wall_0_wipe_dist = 0, bool spiralize = false, float flow_ratio = 1.0);
 
     /*!
      * Add polygons to the gcode with optimized order.
@@ -445,8 +407,9 @@ public:
      * \param z_seam_pos The location near where to start each part in case \p z_seam_type is 'back'
      * \param wall_0_wipe_dist The distance to travel along each polygon after it has been laid down, in order to wipe the start and end of the wall together
      * \param spiralize Whether to gradually increase the z height from the normal layer height to the height of the next layer over each polygon printed
+     * \param flow_ratio The ratio with which to multiply the extrusion amount
      */
-    void addPolygonsByOptimizer(const Polygons& polygons, const GCodePathConfig* config, WallOverlapComputation* wall_overlap_computation = nullptr, EZSeamType z_seam_type = EZSeamType::SHORTEST, Point z_seam_pos = Point(0, 0), coord_t wall_0_wipe_dist = 0, bool spiralize = false);
+    void addPolygonsByOptimizer(Polygons& polygons, GCodePathConfig* config, WallOverlapComputation* wall_overlap_computation = nullptr, EZSeamType z_seam_type = EZSeamType::SHORTEST, Point z_seam_pos = Point(0, 0), coord_t wall_0_wipe_dist = 0, bool spiralize = false, float flow_ratio = 1.0);
 
     /*!
      * Add lines to the gcode with optimized order.
@@ -454,8 +417,9 @@ public:
      * \param config The config of the lines
      * \param space_fill_type The type of space filling used to generate the line segments (should be either Lines or PolyLines!)
      * \param wipe_dist (optional) the distance wiped without extruding after laying down a line.
+     * \param flow_ratio The ratio with which to multiply the extrusion amount
      */
-    void addLinesByOptimizer(const Polygons& polygons, const GCodePathConfig* config, SpaceFillType space_fill_type, int wipe_dist = 0);
+    void addLinesByOptimizer(Polygons& polygons, GCodePathConfig* config, SpaceFillType space_fill_type, int wipe_dist = 0, float flow_ratio = 1.0);
 
     /*!
      * Compute naive time estimates (without accounting for slow down at corners etc.) and naive material estimates (without accounting for MergeInfillLines)
@@ -473,7 +437,20 @@ public:
      * \param gcode The gcode to write the planned paths to
      */
     void writeGCode(GCodeExport& gcode);
-
+    
+    /*!
+     * Complete all GcodePathConfigs by
+     * - altering speeds to conform to speed_print_layer_0 and
+     *   speed_travel_layer_0
+     * - setting the layer_height (and thereby computing the extrusionMM3perMM)
+     */
+    void completeConfigs();
+    
+    /*!
+     * Interpolate between the initial layer speeds and the eventual speeds.
+     */
+    void processInitialLayersSpeedup();
+    
     /*!
      * Whether the current retracted path is to be an extruder switch retraction.
      * This function is used to avoid a G10 S1 after a G10.

src/infill.cpp

@@ -17,7 +17,7 @@ int Infill::computeScanSegmentIdx(int x, int line_width)
     return x / line_width;
 }
 
-void Infill::generate(Polygons& result_polygons, Polygons& result_lines, const SliceMeshStorage* mesh)
+void Infill::generate(Polygons& result_polygons, Polygons& result_lines, SliceMeshStorage* mesh)
 {
     if (in_outline.size() == 0) return;
     if (line_distance == 0) return;
@@ -144,7 +144,7 @@ void Infill::generateTriangleInfill(Polygons& result)
     generateLineInfill(result, line_distance, fill_angle + 120, 0);
 }
 
-void Infill::generateCubicSubDivInfill(Polygons& result, const SliceMeshStorage& mesh)
+void Infill::generateCubicSubDivInfill(Polygons& result, SliceMeshStorage& mesh)
 {
     Polygons uncropped;
     mesh.base_subdiv_cube->generateSubdivisionLines(z, uncropped);

src/infill.h

@@ -80,7 +80,7 @@ public:
      * \param result_lines (output) The resulting line segments (from linear infill types)
      * \param mesh The mesh for which to geenrate infill (should only be used for non-helper objects)
      */
-    void generate(Polygons& result_polygons, Polygons& result_lines, const SliceMeshStorage* mesh = nullptr);
+    void generate(Polygons& result_polygons, Polygons& result_lines, SliceMeshStorage* mesh = nullptr);
 
 private:
     /*!
@@ -148,8 +148,8 @@ private:
      * \param[out] result The resulting lines
      * \param[in] mesh Where the Cubic Subdivision Infill precomputation is stored
      */
-    void generateCubicSubDivInfill(Polygons& result, const SliceMeshStorage& mesh);
-
+    void generateCubicSubDivInfill(Polygons& result, SliceMeshStorage& mesh);
+    
     /*!
      * Convert a mapping from scanline to line_segment-scanline-intersections (\p cut_list) into line segments, using the even-odd rule
      * \param result (output) The resulting lines

src/infill/SpaghettiInfill.cpp

@@ -0,0 +1,139 @@
+/** Copyright (C) 2017 Ultimaker - Released under terms of the AGPLv3 License */
+#include "SpaghettiInfill.h"
+
+namespace cura {
+
+
+void SpaghettiInfill::generateSpaghettiInfill(SliceMeshStorage& mesh)
+{
+    coord_t layer_height = mesh.getSettingInMicrons("layer_height");
+    coord_t line_width = mesh.getSettingInMicrons("infill_line_width");
+    double layer_height_mm = INT2MM(layer_height);
+    int spaghetti_max_layer_count = std::max(1, static_cast<int>(mesh.getSettingInMicrons("spaghetti_max_height") / layer_height));
+    // TODO: account for the initial layer height
+
+    coord_t filling_area_inset = mesh.getSettingInMicrons("spaghetti_inset");
+    
+    if (mesh.getSettingInAngleDegrees("spaghetti_max_infill_angle") >= 90)
+    {
+        return; // infill cannot be combined into pillars
+    }
+    coord_t connection_inset_dist = tan(mesh.getSettingInAngleRadians("spaghetti_max_infill_angle")) * layer_height; // Horizontal component of the spaghetti_max_infill_angle
+
+    std::list<SpaghettiInfill::InfillPillar> pillar_base;
+    size_t min_layer = mesh.getSettingAsCount("bottom_layers") + 1;
+    size_t max_layer = mesh.layers.size() - 1 - mesh.getSettingAsCount("top_layers");
+    for (size_t layer_idx = min_layer; layer_idx <= max_layer; layer_idx++) //Skip every few layers, but extrude more.
+    {
+        SliceLayer& layer = mesh.layers[layer_idx];
+
+        // add infill parts to pillar_base
+        for (SliceLayerPart& slice_layer_part : layer.parts)
+        {
+            std::vector<PolygonsPart> part_infill_parts = slice_layer_part.getOwnInfillArea().splitIntoParts();
+
+            // add parts to pillar_base
+            for (PolygonsPart& infill_part : part_infill_parts)
+            {
+                SpaghettiInfill::InfillPillar& pillar = addPartToPillarBase(infill_part, pillar_base, connection_inset_dist);
+                pillar.top_slice_layer_part = &slice_layer_part;
+                pillar.last_layer_added = layer_idx;
+                pillar.layer_count++;
+            }
+        }
+
+
+        // handle finished pillars
+        for (auto it = pillar_base.begin(); it != pillar_base.end();)
+        {
+            InfillPillar& pillar = *it;
+            if (pillar.layer_count >= spaghetti_max_layer_count
+                || pillar.last_layer_added < static_cast<int>(layer_idx)
+            )
+            {
+                pillar.addToTopSliceLayerPart(layer_height_mm, filling_area_inset, line_width);
+                auto to_be_erased = it;
+                ++it;
+                pillar_base.erase(to_be_erased);
+            }
+            else
+            {
+                ++it;
+            }
+        }
+    }
+    // handle unfinished pillars
+    for (auto it = pillar_base.begin(); it != pillar_base.end(); ++it)
+    {
+        it->addToTopSliceLayerPart(layer_height_mm, filling_area_inset, line_width);
+    }
+}
+
+void SpaghettiInfill::InfillPillar::addToTopSliceLayerPart(double layer_height_mm, coord_t filling_area_inset, coord_t line_width)
+{
+    SliceLayerPart& slice_layer_part = *top_slice_layer_part;
+    double volume = total_area_mm2 * layer_height_mm;
+    assert(volume > 0.0);
+
+    // get filling area
+    Polygons filling_area = top_part.offset(-filling_area_inset);
+    assert(top_part.size() > 0 && top_part[0].size() > 0 && "the top part must be a non-zero area!");
+    if (filling_area.size() == 0)
+    {
+        AABB aabb(top_part);
+        Point inside = (aabb.min + aabb.max) / 2;
+        if (!top_part.inside(inside))
+        {
+            inside = top_part[0][0];
+        }
+        filling_area = PolygonsPart();
+        PolygonRef poly = filling_area.newPoly();
+        poly.emplace_back(inside + Point(-line_width / 2 - 10, line_width / 2 + 10));
+        poly.emplace_back(inside + Point(line_width / 2 + 10, line_width / 2 + 10));
+        poly.emplace_back(inside + Point(line_width / 2 + 10, -line_width / 2 - 10));
+        poly.emplace_back(inside + Point(-line_width / 2 - 10, -line_width / 2 - 10));
+    }
+    slice_layer_part.spaghetti_infill_volumes.emplace_back(top_part, volume);
+}
+
+bool SpaghettiInfill::InfillPillar::isConnected(const PolygonsPart& infill_part) const
+{
+    Polygons insetted = infill_part.offset(-connection_inset_dist);
+    if (insetted.intersection(top_part).size() > 0)
+    {
+        return true;
+    }
+    else
+    {
+        return false;
+    }
+}
+
+SpaghettiInfill::InfillPillar& SpaghettiInfill::addPartToPillarBase(const PolygonsPart& infill_part, std::list<SpaghettiInfill::InfillPillar>& pillar_base, coord_t connection_inset_dist)
+{
+    std::list<SpaghettiInfill::InfillPillar>::iterator ret = pillar_base.end();
+    for (auto it = pillar_base.begin(); it != pillar_base.end(); ++it)
+    {
+        InfillPillar& pillar = *it;
+        if (pillar.isConnected(infill_part))
+        {
+            pillar.total_area_mm2 += INT2MM(INT2MM(infill_part.area()));
+            pillar.top_part = infill_part;
+            if (ret != pillar_base.end())
+            { // connecting two pillars of the layer below via one area on this layer
+                pillar.total_area_mm2 += ret->total_area_mm2;
+                pillar_base.erase(ret);
+            }
+            ret = it;
+        }
+    }
+    if (ret == pillar_base.end())
+    { // couldn't connect to any existing pillar
+        pillar_base.emplace_back(infill_part, connection_inset_dist);
+        return pillar_base.back();
+    }
+    return *ret;
+}
+
+
+}//namespace cura

src/infill/SpaghettiInfill.h

@@ -0,0 +1,95 @@
+/** Copyright (C) 2017 Ultimaker - Released under terms of the AGPLv3 License */
+#ifndef INFILL_SPAGHETTI_INFILL_H
+#define INFILL_SPAGHETTI_INFILL_H
+
+#include <list>
+
+#include "../utils/intpoint.h"
+#include "../utils/polygon.h"
+#include "../sliceDataStorage.h"
+
+namespace cura {
+
+/*!
+ * Spaghetti infill is a type of infill which fills every so many layers, but extrudes as much filament corresponding to the total unfilled volume under the filling area.
+ * 
+ * A filling layer is inserted when a a pillar of infill areas is becoming too high, or when the angle between the filling areas is too shallow.
+ * 
+ * The filling area might be smaller than the actual infill area, so that we fill the pillar from a smaller top area.
+ * 
+ * Infill pillars can join each other if they are connected on the top. The total volume will then be extruded from the top.
+ * 
+ * Where the model spits into two from bottom to top, one of the top pieces will be connected to the lower part as one big pillar, while a new pillar will be generated for the other top part.
+ * Which part the base will be connected to is arbitrary.
+ * 
+ */
+class SpaghettiInfill
+{
+public:
+    /*!
+     * Generate the filling areas and corresponding volume to extrude over such areas for spaghetti infill.
+     */
+    static void generateSpaghettiInfill(SliceMeshStorage& mesh);
+
+protected:
+    struct InfillPillar
+    {
+        SliceLayerPart* top_slice_layer_part = nullptr; //!< A reference to the slice_layer_part from which the top part is generated
+        PolygonsPart top_part; //!< The top area of this pillar
+        double total_area_mm2; //!< The total volume of the pillar divided by the layer height
+        coord_t connection_inset_dist; //!< Horizontal component of the spaghetti_max_infill_angle: the distance insetted corresponding to the maximum angle which can be filled by spaghetti infill.
+        int layer_count; //!< The height of the pillar in numer of layers
+        int last_layer_added = -1; //!< The last layer from which areas got added to this pillar
+
+        /*!
+         * Basic constructor of a pillar from a single area, which is to be the top of the new pillar
+         * 
+         * \param _top_part The area which is the base and the top of the new pillar
+         * \param connection_inset_dist Horizontal component of the spaghetti_max_infill_angle
+         */
+        InfillPillar(const PolygonsPart& _top_part, coord_t connection_inset_dist)
+        : top_part(_top_part) // TODO: prevent copy construction! Is that possible?
+        , total_area_mm2(INT2MM(INT2MM(top_part.area())))
+        , connection_inset_dist(connection_inset_dist)
+        , layer_count(1)
+        {
+        }
+
+        /*!
+         * Check whether the top of this pillar is connected (enough) to the given \p infill_part.
+         * It is assumed the infill_part is on the layer directly above the top part of this pillar.
+         * 
+         * \param infill_part The part to check for connectivity
+         * \return Whether the infill part can be incorporated in this pillar
+         */
+        bool isConnected(const PolygonsPart& infill_part) const;
+
+        /*!
+         * Register the volume of this infill pillar in the sliceDataStorage.
+         * The filling area and the volume are saved in \ref SliceLayerPart::spaghetti_infill_volumes
+         * 
+         * Note that the filling area is different from the infill area, because the spaghetti can curl toward the sides.
+         * 
+         * \param layer_height_mm The layer height in millimeters
+         * \param filling_area_inset The inset from the boundary of the walls to get from the infill area to the filling area
+         * \param line_width The line width used to generate an area just large enough for infill lines to be generated, when the infill area would otherwise be too small to get infill
+         */
+        void addToTopSliceLayerPart(double layer_height_mm, coord_t filling_area_inset, coord_t line_width);
+    };
+private:
+    /*!
+     * Add an area to the pillar base:
+     * - add it to an existing pillar if possible
+     * - otherwise create a new pillar for this area
+     * The pillar to which the area was added is returned
+     * 
+     * \param infill_part The area to add to the base
+     * \param pillar_base The collection of pillars used up till the current layer
+     * \param connection_inset_dist The distance insetted corresponding to the maximum angle which can be filled by spaghetti infill
+     */
+    static InfillPillar& addPartToPillarBase(const PolygonsPart& infill_part, std::list<InfillPillar>& pillar_base, coord_t connection_inset_dist);
+};
+
+}//namespace cura
+
+#endif//INFILL_SPAGHETTI_INFILL_H

src/layerPart.cpp

@@ -44,10 +44,7 @@ void createLayerWithParts(SliceLayer& storageLayer, SlicerLayer* layer, bool uni
 }
 void createLayerParts(SliceMeshStorage& mesh, Slicer* slicer, bool union_layers, bool union_all_remove_holes)
 {
-    const auto total_layers = slicer->layers.size();
-    assert(mesh.layers.size() == total_layers);
-#pragma omp parallel for default(none) shared(mesh,slicer) firstprivate(union_layers,union_all_remove_holes) schedule(dynamic)
-    for(unsigned int layer_nr = 0; layer_nr < total_layers; layer_nr++)
+    for(unsigned int layer_nr = 0; layer_nr < slicer->layers.size(); layer_nr++)
     {
         mesh.layers[layer_nr].sliceZ = slicer->layers[layer_nr].z;
         mesh.layers[layer_nr].printZ = slicer->layers[layer_nr].z;

src/main.cpp

@@ -20,8 +20,6 @@
 
 #include "settings/SettingsToGV.h"
 
-#include <omp.h> // omp_get_num_threads
-
 namespace cura
 {
     
@@ -330,19 +328,7 @@ int main(int argc, char **argv)
         print_usage();
         exit(1);
     }
-
-#pragma omp parallel
-    {
-#pragma omp master
-        {
-#ifdef _OPENMP
-            log("OpenMP multithreading enabled, likely number of threads to be used: %u\n", omp_get_num_threads());
-#else
-            log("OpenMP multithreading disabled\n");
-#endif
-        }
-    }
-
+    
     if (stringcasecompare(argv[1], "connect") == 0)
     {
         connect(argc, argv);

src/pathOrderOptimizer.cpp

@@ -16,7 +16,7 @@ void PathOrderOptimizer::optimize()
     bool picked[polygons.size()];
     memset(picked, false, sizeof(bool) * polygons.size());/// initialized as falses
     
-    for (ConstPolygonRef poly : polygons) /// find closest point to initial starting point within each polygon +initialize picked
+    for (PolygonRef poly : polygons) /// find closest point to initial starting point within each polygon +initialize picked
     {
         int best = -1;
         float bestDist = std::numeric_limits<float>::infinity();
@@ -102,15 +102,15 @@ int PathOrderOptimizer::getPolyStart(Point prev_point, int poly_idx)
 
 int PathOrderOptimizer::getClosestPointInPolygon(Point prev_point, int poly_idx)
 {
-    ConstPolygonRef poly = polygons[poly_idx];
+    PolygonRef poly = polygons[poly_idx];
 
     int best_point_idx = -1;
     float best_point_score = std::numeric_limits<float>::infinity();
     Point p0 = poly.back();
     for (unsigned int point_idx = 0; point_idx < poly.size(); point_idx++)
     {
-        const Point& p1 = poly[point_idx];
-        const Point& p2 = poly[(point_idx + 1) % poly.size()];
+        Point& p1 = poly[point_idx];
+        Point& p2 = poly[(point_idx + 1) % poly.size()];
         int64_t dist = vSize2(p1 - prev_point);
         float is_on_inside_corner_score = -LinearAlg2D::getAngleLeft(p0, p1, p2) / M_PI * 5000 * 5000; // prefer inside corners
         // this score is in the order of 5 mm
@@ -143,7 +143,7 @@ void LineOrderOptimizer::optimize()
     {
         int best_point_idx = -1;
         float best_point_dist = std::numeric_limits<float>::infinity();
-        ConstPolygonRef poly = polygons[poly_idx];
+        PolygonRef poly = polygons[poly_idx];
         for (unsigned int point_idx = 0; point_idx < poly.size(); point_idx++) /// get closest point from polygon
         {
             float dist = vSize2f(poly[point_idx] - startPoint);
@@ -199,13 +199,13 @@ void LineOrderOptimizer::optimize()
 
         if (best_line_idx > -1) /// should always be true; we should have been able to identify the best next polygon
         {
-            ConstPolygonRef best_line = polygons[best_line_idx];
+            PolygonRef best_line = polygons[best_line_idx];
             assert(best_line.size() == 2);
 
             int line_start_point_idx = polyStart[best_line_idx];
             int line_end_point_idx = line_start_point_idx * -1 + 1; /// 1 -> 0 , 0 -> 1
-            const Point& line_start = best_line[line_start_point_idx];
-            const Point& line_end = best_line[line_end_point_idx];
+            Point& line_start = best_line[line_start_point_idx];
+            Point& line_end = best_line[line_end_point_idx];
             prev_point = line_end;
             incoming_perpundicular_normal = turn90CCW(normal(line_end - line_start, 1000));
 
@@ -221,8 +221,8 @@ void LineOrderOptimizer::optimize()
 
 inline void LineOrderOptimizer::updateBestLine(unsigned int poly_idx, int& best, float& best_score, Point prev_point, Point incoming_perpundicular_normal)
 {
-    const Point& p0 = polygons[poly_idx][0];
-    const Point& p1 = polygons[poly_idx][1];
+    Point& p0 = polygons[poly_idx][0];
+    Point& p1 = polygons[poly_idx][1];
     float dot_score = getAngleScore(incoming_perpundicular_normal, p0, p1);
     { /// check distance to first point on line (0)
         float score = vSize2f(p0 - prev_point) + dot_score; // prefer 90 degree corners

src/pathOrderOptimizer.h

@@ -20,7 +20,7 @@ public:
     EZSeamType type;
     Point startPoint; //!< A location near the prefered start location
     Point z_seam_pos; //!< The position near where to create the z_seam (if \ref PathOrderOptimizer::type == 'back')
-    std::vector<ConstPolygonRef> polygons; //!< the parts of the layer (in arbitrary order)
+    std::vector<PolygonRef> polygons; //!< the parts of the layer (in arbitrary order)
     std::vector<int> polyStart; //!< polygons[i][polyStart[i]] = point of polygon i which is to be the starting point in printing the polygon
     std::vector<int> polyOrder; //!< the optimized order as indices in #polygons
 
@@ -33,15 +33,10 @@ public:
 
     void addPolygon(PolygonRef polygon)
     {
-        this->polygons.emplace_back(polygon);
+        this->polygons.push_back(polygon);
     }
 
-    void addPolygon(ConstPolygonRef polygon)
-    {
-        this->polygons.emplace_back(polygon);
-    }
-
-    void addPolygons(const Polygons& polygons)
+    void addPolygons(Polygons& polygons)
     {
         for(unsigned int i=0;i<polygons.size(); i++)
             this->polygons.push_back(polygons[i]);
@@ -71,7 +66,7 @@ class LineOrderOptimizer
 {
 public:
     Point startPoint; //!< The location of the nozzle before starting to print the current layer
-    std::vector<ConstPolygonRef> polygons; //!< the parts of the layer (in arbitrary order)
+    std::vector<PolygonRef> polygons; //!< the parts of the layer (in arbitrary order)
     std::vector<int> polyStart; //!< polygons[i][polyStart[i]] = point of polygon i which is to be the starting point in printing the polygon
     std::vector<int> polyOrder; //!< the optimized order as indices in #polygons
 
@@ -85,11 +80,6 @@ public:
         this->polygons.push_back(polygon);
     }
 
-    void addPolygon(ConstPolygonRef polygon)
-    {
-        this->polygons.push_back(polygon);
-    }
-
     void addPolygons(Polygons& polygons)
     {
         for(unsigned int i=0;i<polygons.size(); i++)

src/pathPlanning/Comb.cpp

@@ -6,7 +6,6 @@
 #include <unordered_set>
 
 #include "../utils/polygonUtils.h"
-#include "../utils/linearAlg2D.h"
 #include "../utils/PolygonsPointIndex.h"
 #include "../sliceDataStorage.h"
 #include "../utils/SVG.h"
@@ -23,7 +22,7 @@ Polygons& Comb::getBoundaryOutside()
     return *boundary_outside;
 }
   
-Comb::Comb(const SliceDataStorage& storage, int layer_nr, const Polygons& comb_boundary_inside, int64_t comb_boundary_offset, bool travel_avoid_other_parts, int64_t travel_avoid_distance)
+Comb::Comb(SliceDataStorage& storage, int layer_nr, Polygons& comb_boundary_inside, int64_t comb_boundary_offset, bool travel_avoid_other_parts, int64_t travel_avoid_distance)
 : storage(storage)
 , layer_nr(layer_nr)
 , offset_from_outlines(comb_boundary_offset) // between second wall and infill / other walls
@@ -32,7 +31,7 @@ Comb::Comb(const SliceDataStorage& storage, int layer_nr, const Polygons& comb_b
 , offset_from_inside_to_outside(offset_from_outlines + offset_from_outlines_outside)
 , max_crossing_dist2(offset_from_inside_to_outside * offset_from_inside_to_outside * 2) // so max_crossing_dist = offset_from_inside_to_outside * sqrt(2) =approx 1.5 to allow for slightly diagonal crossings and slightly inaccurate crossing computation
 , avoid_other_parts(travel_avoid_other_parts)
-, boundary_inside( comb_boundary_inside ) // copy the boundary, because the partsView_inside will reorder the polygons
+, boundary_inside( comb_boundary_inside )
 , partsView_inside( boundary_inside.splitIntoPartsView() ) // WARNING !! changes the order of boundary_inside !!
 , inside_loc_to_line(PolygonUtils::createLocToLineGrid(boundary_inside, comb_boundary_offset))
 , boundary_outside(
@@ -214,7 +213,7 @@ Comb::Crossing::Crossing(const Point& dest_point, const bool dest_is_inside, con
 {
     if (dest_is_inside)
     {
-        dest_crossing_poly.emplace(boundary_inside[dest_part_boundary_crossing_poly_idx]); // initialize with most obvious poly, cause mostly a combing move will move outside the part, rather than inside a hole in the part
+        dest_crossing_poly = boundary_inside[dest_part_boundary_crossing_poly_idx]; // initialize with most obvious poly, cause mostly a combing move will move outside the part, rather than inside a hole in the part
     }
 }
 
@@ -333,7 +332,7 @@ bool Comb::Crossing::findOutside(const Polygons& outside, const Point close_to,
 }
 
 
-std::shared_ptr<std::pair<ClosestPolygonPoint, ClosestPolygonPoint>> Comb::Crossing::findBestCrossing(const Polygons& outside, ConstPolygonRef from, const Point estimated_start, const Point estimated_end, Comb& comber)
+std::shared_ptr<std::pair<ClosestPolygonPoint, ClosestPolygonPoint>> Comb::Crossing::findBestCrossing(const Polygons& outside, const PolygonRef from, const Point estimated_start, const Point estimated_end, Comb& comber)
 {
     ClosestPolygonPoint* best_in = nullptr;
     ClosestPolygonPoint* best_out = nullptr;

src/pathPlanning/Comb.h

@@ -48,7 +48,7 @@ private:
         Point in_or_mid; //!< The point on the inside boundary, or in between the inside and outside boundary if the start/end point isn't inside the inside boudary
         Point out; //!< The point on the outside boundary
         PolygonsPart dest_part; //!< The assembled inside-boundary PolygonsPart in which the dest_point lies. (will only be initialized when Crossing::dest_is_inside holds)
-        std::optional<ConstPolygonRef> dest_crossing_poly; //!< The polygon of the part in which dest_point lies, which will be crossed (often will be the outside polygon)
+        std::optional<PolygonRef> dest_crossing_poly; //!< The polygon of the part in which dest_point lies, which will be crossed (often will be the outside polygon)
         const Polygons& boundary_inside; //!< The inside boundary as in \ref Comb::boundary_inside
         const LocToLineGrid* inside_loc_to_line; //!< The loc to line grid \ref Comb::inside_loc_to_line
 
@@ -97,11 +97,11 @@ private:
          * \param comber[in] The combing calculator which has references to the offsets and boundaries to use in combing.
          * \return A pair of which the first is the crossing point on the inside boundary and the second the crossing point on the outside boundary
          */
-        std::shared_ptr<std::pair<ClosestPolygonPoint, ClosestPolygonPoint>> findBestCrossing(const Polygons& outside, ConstPolygonRef from, Point estimated_start, Point estimated_end, Comb& comber);
+        std::shared_ptr<std::pair<ClosestPolygonPoint, ClosestPolygonPoint>> findBestCrossing(const Polygons& outside, const PolygonRef from, Point estimated_start, Point estimated_end, Comb& comber);
     };
 
 
-    const SliceDataStorage& storage; //!< The storage from which to compute the outside boundary, when needed.
+    SliceDataStorage& storage; //!< The storage from which to compute the outside boundary, when needed.
     const int layer_nr; //!< The layer number for the layer for which to compute the outside boundary, when needed.
     
     const int64_t offset_from_outlines; //!< Offset from the boundary of a part to the comb path. (nozzle width / 2)
@@ -115,8 +115,8 @@ private:
 
     const bool avoid_other_parts; //!< Whether to perform inverse combing a.k.a. avoid parts.
     
-    Polygons boundary_inside; //!< The boundary within which to comb. (Will be reordered by the partsView_inside)
-    const PartsView partsView_inside; //!< Structured indices onto boundary_inside which shows which polygons belong to which part. 
+    Polygons& boundary_inside; //!< The boundary within which to comb.
+    PartsView partsView_inside; //!< Structured indices onto boundary_inside which shows which polygons belong to which part. 
     LocToLineGrid* inside_loc_to_line; //!< The SparsePointGridInclusive mapping locations to line segments of the inner boundary.
     LazyInitialization<Polygons> boundary_outside; //!< The boundary outside of which to stay to avoid collision with other layer parts. This is a pointer cause we only compute it when we move outside the boundary (so not when there is only a single part in the layer)
     LazyInitialization<LocToLineGrid, Comb*, const int64_t> outside_loc_to_line; //!< The SparsePointGridInclusive mapping locations to line segments of the outside boundary.
@@ -153,7 +153,7 @@ public:
      * \param travel_avoid_other_parts Whether to avoid other layer parts when traveling through air.
      * \param travel_avoid_distance The distance by which to avoid other layer parts when traveling through air.
      */
-    Comb(const SliceDataStorage& storage, int layer_nr, const Polygons& comb_boundary_inside, int64_t offset_from_outlines, bool travel_avoid_other_parts, int64_t travel_avoid_distance);
+    Comb(SliceDataStorage& storage, int layer_nr, Polygons& comb_boundary_inside, int64_t offset_from_outlines, bool travel_avoid_other_parts, int64_t travel_avoid_distance);
 
     ~Comb();
 

src/pathPlanning/GCodePath.h

@@ -23,7 +23,7 @@ namespace cura
 class GCodePath
 {
 public:
-    const GCodePathConfig* config; //!< The configuration settings of the path.
+    GCodePathConfig* config; //!< The configuration settings of the path.
     SpaceFillType space_fill_type; //!< The type of space filling of which this path is a part
     float flow; //!< A type-independent flow configuration (used for wall overlap compensation)
     bool retract; //!< Whether the path is a move path preceded by a retraction move; whether the path is a retracted move path. 

src/settings/PathConfigStorage.cpp

@@ -1,235 +0,0 @@
-/** Copyright (C) 2017 Ultimaker - Released under terms of the AGPLv3 License */
-#include "PathConfigStorage.h"
-
-#include "settings.h" // MAX_INFILL_COMBINE
-#include "../sliceDataStorage.h" // SliceDataStorage
-
-
-namespace cura
-{
-
-GCodePathConfig getPerimeterGapConfig(const SliceMeshStorage& mesh, int layer_thickness)
-{
-    // The perimeter gap config follows the skin config, but has a different line width:
-    // wall_line_width_x divided by two because the gaps are between 0 and 1 times the wall line width
-    const int perimeter_gaps_line_width = mesh.getSettingInMicrons("wall_line_width_x") / 2;
-    double perimeter_gaps_speed = mesh.getSettingInMillimetersPerSecond("speed_topbottom");
-    if (mesh.getSettingBoolean("speed_equalize_flow_enabled"))
-    {
-        perimeter_gaps_speed = perimeter_gaps_speed * mesh.getSettingInMicrons("skin_line_width") / perimeter_gaps_line_width;
-    }
-    return GCodePathConfig(
-            PrintFeatureType::Skin
-            , perimeter_gaps_line_width
-            , layer_thickness
-            , mesh.getSettingInPercentage("material_flow")
-            , GCodePathConfig::SpeedDerivatives{perimeter_gaps_speed, mesh.getSettingInMillimetersPerSecond("acceleration_topbottom"), mesh.getSettingInMillimetersPerSecond("jerk_topbottom")}
-        );
-}
-
-PathConfigStorage::MeshPathConfigs::MeshPathConfigs(const SliceMeshStorage& mesh, int layer_thickness)
-: inset0_config(
-    PrintFeatureType::OuterWall
-    , mesh.getSettingInMicrons("wall_line_width_0")
-    , layer_thickness
-    , mesh.getSettingInPercentage("material_flow")
-    , GCodePathConfig::SpeedDerivatives{mesh.getSettingInMillimetersPerSecond("speed_wall_0"), mesh.getSettingInMillimetersPerSecond("acceleration_wall_0"), mesh.getSettingInMillimetersPerSecond("jerk_wall_0")}
-)
-, insetX_config(
-    PrintFeatureType::InnerWall
-    , mesh.getSettingInMicrons("wall_line_width_x")
-    , layer_thickness
-    , mesh.getSettingInPercentage("material_flow")
-    , GCodePathConfig::SpeedDerivatives{mesh.getSettingInMillimetersPerSecond("speed_wall_x"), mesh.getSettingInMillimetersPerSecond("acceleration_wall_x"), mesh.getSettingInMillimetersPerSecond("jerk_wall_x")}
-)
-, skin_config(
-    PrintFeatureType::Skin
-    , mesh.getSettingInMicrons("skin_line_width")
-    , layer_thickness
-    , mesh.getSettingInPercentage("material_flow")
-    , GCodePathConfig::SpeedDerivatives{mesh.getSettingInMillimetersPerSecond("speed_topbottom"), mesh.getSettingInMillimetersPerSecond("acceleration_topbottom"), mesh.getSettingInMillimetersPerSecond("jerk_topbottom")}
-)
-
-, perimeter_gap_config(getPerimeterGapConfig(mesh, layer_thickness))
-{
-    infill_config.reserve(MAX_INFILL_COMBINE);
-    for (int combine_idx = 0; combine_idx < MAX_INFILL_COMBINE; combine_idx++)
-    {
-        infill_config.emplace_back(
-                PrintFeatureType::Infill
-                , mesh.getSettingInMicrons("infill_line_width") * (combine_idx + 1)
-                , layer_thickness
-                , mesh.getSettingInPercentage("material_flow")
-                , GCodePathConfig::SpeedDerivatives{mesh.getSettingInMillimetersPerSecond("speed_infill"), mesh.getSettingInMillimetersPerSecond("acceleration_infill"), mesh.getSettingInMillimetersPerSecond("jerk_infill")}
-            );
-    }
-}
-
-PathConfigStorage::PathConfigStorage(const SliceDataStorage& storage, int layer_nr, int layer_thickness)
-: adhesion_extruder_train(storage.meshgroup->getExtruderTrain(storage.getSettingAsIndex("adhesion_extruder_nr")))
-, support_infill_train(storage.meshgroup->getExtruderTrain(storage.getSettingAsIndex("support_infill_extruder_nr")))
-, support_interface_train(storage.meshgroup->getExtruderTrain(storage.getSettingAsIndex("support_interface_extruder_nr")))
-, raft_base_config(
-            PrintFeatureType::SupportInterface
-            , adhesion_extruder_train->getSettingInMicrons("raft_base_line_width")
-            , adhesion_extruder_train->getSettingInMicrons("raft_base_thickness")
-            , adhesion_extruder_train->getSettingInPercentage("material_flow")
-            , GCodePathConfig::SpeedDerivatives{adhesion_extruder_train->getSettingInMillimetersPerSecond("raft_base_speed"), adhesion_extruder_train->getSettingInMillimetersPerSecond("raft_base_acceleration"), adhesion_extruder_train->getSettingInMillimetersPerSecond("raft_base_jerk")}
-        )
-, raft_interface_config(
-            PrintFeatureType::Support
-            , adhesion_extruder_train->getSettingInMicrons("raft_interface_line_width")
-            , adhesion_extruder_train->getSettingInMicrons("raft_interface_thickness")
-            , adhesion_extruder_train->getSettingInPercentage("material_flow")
-            , GCodePathConfig::SpeedDerivatives{adhesion_extruder_train->getSettingInMillimetersPerSecond("raft_interface_speed"), adhesion_extruder_train->getSettingInMillimetersPerSecond("raft_interface_acceleration"), adhesion_extruder_train->getSettingInMillimetersPerSecond("raft_interface_jerk")}
-        )
-, raft_surface_config(
-            PrintFeatureType::SupportInterface
-            , adhesion_extruder_train->getSettingInMicrons("raft_surface_line_width")
-            , adhesion_extruder_train->getSettingInMicrons("raft_surface_thickness")
-            , adhesion_extruder_train->getSettingInPercentage("material_flow")
-            , GCodePathConfig::SpeedDerivatives{adhesion_extruder_train->getSettingInMillimetersPerSecond("raft_surface_speed"), adhesion_extruder_train->getSettingInMillimetersPerSecond("raft_surface_acceleration"), adhesion_extruder_train->getSettingInMillimetersPerSecond("raft_surface_jerk")}
-        )
-, support_infill_config(
-            PrintFeatureType::Support
-            , support_infill_train->getSettingInMicrons("support_line_width")
-            , layer_thickness
-            , support_infill_train->getSettingInPercentage("material_flow")
-            , GCodePathConfig::SpeedDerivatives{support_infill_train->getSettingInMillimetersPerSecond("speed_support_infill"), support_infill_train->getSettingInMillimetersPerSecond("acceleration_support_infill"), support_infill_train->getSettingInMillimetersPerSecond("jerk_support_infill")}
-        )
-, support_interface_config(
-            PrintFeatureType::SupportInterface
-            , support_interface_train->getSettingInMicrons("support_interface_line_width")
-            , layer_thickness
-            , support_interface_train->getSettingInPercentage("material_flow")
-            , GCodePathConfig::SpeedDerivatives{support_interface_train->getSettingInMillimetersPerSecond("speed_support_interface"), support_interface_train->getSettingInMillimetersPerSecond("acceleration_support_interface"), support_interface_train->getSettingInMillimetersPerSecond("jerk_support_interface")}
-        )
-{
-    int extruder_count = storage.meshgroup->getExtruderCount();
-    travel_config_per_extruder.reserve(extruder_count);
-    skirt_brim_config.reserve(extruder_count);
-    prime_tower_config_per_extruder.reserve(extruder_count);
-    for (int extruder_nr = 0; extruder_nr < extruder_count; extruder_nr++)
-    {
-        const ExtruderTrain* train = storage.meshgroup->getExtruderTrain(extruder_nr);
-        travel_config_per_extruder.emplace_back(
-                PrintFeatureType::MoveCombing
-                , 0
-                , 0
-                , 0.0
-                , GCodePathConfig::SpeedDerivatives{train->getSettingInMillimetersPerSecond("speed_travel"), train->getSettingInMillimetersPerSecond("acceleration_travel"), train->getSettingInMillimetersPerSecond("jerk_travel")}
-            );
-        skirt_brim_config.emplace_back(
-                PrintFeatureType::SkirtBrim
-                , train->getSettingInMicrons("skirt_brim_line_width")
-                , layer_thickness
-                , train->getSettingInPercentage("material_flow")
-                , GCodePathConfig::SpeedDerivatives{train->getSettingInMillimetersPerSecond("skirt_brim_speed"), train->getSettingInMillimetersPerSecond("acceleration_skirt_brim"), train->getSettingInMillimetersPerSecond("jerk_skirt_brim")}
-            );
-        prime_tower_config_per_extruder.emplace_back(
-                PrintFeatureType::SupportInfill
-                , train->getSettingInMicrons("prime_tower_line_width")
-                , layer_thickness
-                , train->getSettingInPercentage("prime_tower_flow")
-                , GCodePathConfig::SpeedDerivatives{train->getSettingInMillimetersPerSecond("speed_prime_tower"), train->getSettingInMillimetersPerSecond("acceleration_prime_tower"), train->getSettingInMillimetersPerSecond("jerk_prime_tower")}
-            );
-    }
-
-    mesh_configs.reserve(storage.meshes.size());
-    for (const SliceMeshStorage& mesh_storage : storage.meshes)
-    {
-        mesh_configs.emplace_back(mesh_storage, layer_thickness);
-    }
-
-    int initial_speedup_layer_count = storage.getSettingAsCount("speed_slowdown_layers");
-    if (layer_nr < initial_speedup_layer_count)
-    {
-        handleInitialLayerSpeedup(storage, layer_nr, initial_speedup_layer_count);
-    }
-}
-
-void cura::PathConfigStorage::handleInitialLayerSpeedup(const SliceDataStorage& storage, int layer_nr, int initial_speedup_layer_count)
-{
-    std::vector<GCodePathConfig::SpeedDerivatives> global_first_layer_config_per_extruder;
-    global_first_layer_config_per_extruder.reserve(storage.meshgroup->getExtruderCount());
-    for (int extruder_nr = 0; extruder_nr < storage.meshgroup->getExtruderCount(); extruder_nr++)
-    {
-        const ExtruderTrain* extruder = storage.meshgroup->getExtruderTrain(extruder_nr);
-        global_first_layer_config_per_extruder.emplace_back(
-            GCodePathConfig::SpeedDerivatives{
-                extruder->getSettingInMillimetersPerSecond("speed_print_layer_0")
-                , extruder->getSettingInMillimetersPerSecond("acceleration_print_layer_0")
-                , extruder->getSettingInMillimetersPerSecond("jerk_print_layer_0")
-            });
-    }
-
-    { // support
-        if (layer_nr < initial_speedup_layer_count)
-        {
-            int extruder_nr_support_infill = storage.getSettingAsIndex((layer_nr <= 0)? "support_extruder_nr_layer_0" : "support_infill_extruder_nr");
-            GCodePathConfig::SpeedDerivatives& first_layer_config_infill = global_first_layer_config_per_extruder[extruder_nr_support_infill];
-            support_infill_config.smoothSpeed(first_layer_config_infill, std::max(0, layer_nr), initial_speedup_layer_count);
-
-            int extruder_nr_support_interface = storage.getSettingAsIndex("support_interface_extruder_nr");
-            GCodePathConfig::SpeedDerivatives& first_layer_config_interface = global_first_layer_config_per_extruder[extruder_nr_support_interface];
-            support_interface_config.smoothSpeed(first_layer_config_interface, std::max(0, layer_nr), initial_speedup_layer_count);
-        }
-    }
-
-    { // extruder configs: travel, skirt/brim (= shield)
-        for (int extruder_nr = 0; extruder_nr < storage.meshgroup->getExtruderCount(); ++extruder_nr)
-        {
-            const ExtruderTrain* train = storage.meshgroup->getExtruderTrain(extruder_nr);
-            GCodePathConfig::SpeedDerivatives initial_layer_speed_config{
-                    train->getSettingInMillimetersPerSecond("speed_travel_layer_0")
-                    , train->getSettingInMillimetersPerSecond("acceleration_travel_layer_0")
-                    , train->getSettingInMillimetersPerSecond("jerk_travel_layer_0")
-            };
-            GCodePathConfig& travel = travel_config_per_extruder[extruder_nr];
-
-            travel.smoothSpeed(initial_layer_speed_config, std::max(0, layer_nr), initial_speedup_layer_count);
-
-            // don't smooth speed for the skirt/brim!
-            // NOTE: not smoothing skirt/brim means the speeds are also not smoothed for the draft/ooze shield
-
-            GCodePathConfig& prime_tower = prime_tower_config_per_extruder[extruder_nr];
-
-            prime_tower.smoothSpeed(initial_layer_speed_config, std::max(0, layer_nr), initial_speedup_layer_count);
-        }
-
-    }
-
-    { // meshes
-        for (unsigned int mesh_idx = 0; mesh_idx < storage.meshes.size(); mesh_idx++)
-        {
-            const SliceMeshStorage& mesh = storage.meshes[mesh_idx];
-
-
-            GCodePathConfig::SpeedDerivatives initial_layer_speed_config{
-                    mesh.getSettingInMillimetersPerSecond("speed_print_layer_0")
-                    , mesh.getSettingInMillimetersPerSecond("acceleration_print_layer_0")
-                    , mesh.getSettingInMillimetersPerSecond("jerk_print_layer_0")
-            };
-
-            MeshPathConfigs& mesh_config = mesh_configs[mesh_idx];
-            //Outer wall speed (per mesh).
-            mesh_config.inset0_config.smoothSpeed(initial_layer_speed_config, layer_nr, initial_speedup_layer_count);
-
-            //Inner wall speed (per mesh).
-            mesh_config.insetX_config.smoothSpeed(initial_layer_speed_config, layer_nr, initial_speedup_layer_count);
-
-            //Skin speed (per mesh).
-            mesh_config.skin_config.smoothSpeed(initial_layer_speed_config, layer_nr, initial_speedup_layer_count);
-            mesh_config.perimeter_gap_config.smoothSpeed(initial_layer_speed_config, layer_nr, initial_speedup_layer_count);
-
-            for (unsigned int idx = 0; idx < MAX_INFILL_COMBINE; idx++)
-            {
-                //Infill speed (per combine part per mesh).
-                mesh_config.infill_config[idx].smoothSpeed(initial_layer_speed_config, layer_nr, initial_speedup_layer_count);
-            }
-        }
-    }
-}
-
-
-}//namespace cura

src/settings/PathConfigStorage.h

@@ -1,63 +0,0 @@
-/** Copyright (C) 2017 Ultimaker - Released under terms of the AGPLv3 License */
-#ifndef SETTINGS_PATH_CONFIGS_H
-#define SETTINGS_PATH_CONFIGS_H
-
-#include <vector>
-
-#include "../utils/intpoint.h" // coord_t
-#include "../GCodePathConfig.h"
-
-namespace cura
-{
-
-class SliceDataStorage; // forward decl for SliceDataStorage
-class SliceMeshStorage; // forward decl for SliceDataStorage
-class ExtruderTrain; // forward decl for SliceDataStorage
-
-/*!
- * A class to represent all configurations for all features types of printed lines in a meshgroup.
- */
-class PathConfigStorage
-{
-private:
-    const ExtruderTrain* adhesion_extruder_train;
-    const ExtruderTrain* support_infill_train;
-    const ExtruderTrain* support_interface_train;
-public:
-    class MeshPathConfigs
-    {
-    public:
-        GCodePathConfig inset0_config;
-        GCodePathConfig insetX_config;
-        GCodePathConfig skin_config;
-        GCodePathConfig perimeter_gap_config;
-        std::vector<GCodePathConfig> infill_config;
-
-        MeshPathConfigs(const SliceMeshStorage& mesh, int layer_thickness);
-    };
-    
-    GCodePathConfig raft_base_config;
-    GCodePathConfig raft_interface_config;
-    GCodePathConfig raft_surface_config;
-
-    std::vector<GCodePathConfig> travel_config_per_extruder; //!< The config used for travel moves (only speed is set!)
-    std::vector<GCodePathConfig> skirt_brim_config; //!< Configuration for skirt and brim per extruder.
-    std::vector<GCodePathConfig> prime_tower_config_per_extruder; //!< Configuration for the prime tower per extruder.
-
-    GCodePathConfig support_infill_config; //!< The config used to print the normal support, rather than the support interface
-    GCodePathConfig support_interface_config; //!< The config to use to print the dense roofs and bottoms of support
-
-    std::vector<MeshPathConfigs> mesh_configs; //!< For each meash the config for all its feature types
-    
-    /*!
-     * \warning Note that the layer_nr might be below zero for raft (filler) layers
-     */
-    PathConfigStorage(const SliceDataStorage& storage, int layer_nr, int layer_thickness);
-
-private:
-    void handleInitialLayerSpeedup(const SliceDataStorage& storage, int layer_nr, int initial_speedup_layer_count);
-};
-
-}; // namespace cura
-
-#endif // SETTINGS_PATH_CONFIGS_H

src/settings/settings.cpp

@@ -93,23 +93,21 @@ void SettingsBase::setSettingInheritBase(std::string key, const SettingsBaseVirt
 
 std::string SettingsBase::getSettingString(std::string key) const
 {
-    auto value_it = setting_values.find(key);
-    if (value_it != setting_values.end())
+    if (setting_values.find(key) != setting_values.end())
     {
-        return value_it->second;
+        return setting_values.at(key);
     }
-    auto inherit_override_it = setting_inherit_base.find(key);
-    if (inherit_override_it != setting_inherit_base.end())
+    if (setting_inherit_base.find(key) != setting_inherit_base.end())
     {
-        return inherit_override_it->second->getSettingString(key);
+        return setting_inherit_base.at(key)->getSettingString(key);
     }
     if (parent)
     {
         return parent->getSettingString(key);
     }
 
-    cura::logError("Trying to retrieve unregistered setting with no value given: '%s'\n", key.c_str());
-    std::exit(-1);
+    const_cast<SettingsBase&>(*this).setting_values[key] = "";
+    cura::logWarning("Unregistered setting %s\n", key.c_str());
     return "";
 }
 
@@ -428,7 +426,7 @@ FillPerimeterGapMode SettingsBaseVirtual::getSettingAsFillPerimeterGapMode(std::
     return FillPerimeterGapMode::NOWHERE;
 }
 
-CombingMode SettingsBaseVirtual::getSettingAsCombingMode(std::string key) const
+CombingMode SettingsBaseVirtual::getSettingAsCombingMode(std::string key)
 {
     std::string value = getSettingString(key);
     if (value == "off")
@@ -446,7 +444,7 @@ CombingMode SettingsBaseVirtual::getSettingAsCombingMode(std::string key) const
     return CombingMode::ALL;
 }
 
-SupportDistPriority SettingsBaseVirtual::getSettingAsSupportDistPriority(std::string key) const
+SupportDistPriority SettingsBaseVirtual::getSettingAsSupportDistPriority(std::string key)
 {
     std::string value = getSettingString(key);
     if (value == "xy_overrides_z")

src/settings/settings.h

@@ -251,8 +251,8 @@ public:
     EZSeamType getSettingAsZSeamType(std::string key) const;
     ESurfaceMode getSettingAsSurfaceMode(std::string key) const;
     FillPerimeterGapMode getSettingAsFillPerimeterGapMode(std::string key) const;
-    CombingMode getSettingAsCombingMode(std::string key) const;
-    SupportDistPriority getSettingAsSupportDistPriority(std::string key) const;
+    CombingMode getSettingAsCombingMode(std::string key);
+    SupportDistPriority getSettingAsSupportDistPriority(std::string key);
 };
 
 class SettingRegistry;

src/skin.cpp

@@ -10,16 +10,7 @@
 namespace cura 
 {
 
-
-/*
- * This function is executed in a parallel region based on layer_nr.
- * When modifying make sure any changes does not introduce data races.
- *
- * generateSkinAreas reads data from mesh.layers.parts[*].insets and writes to mesh.layers[n].parts[*].skin_parts
- * generateSkinInsets only read/writes the skin_parts from the current layer.
- *
- * generateSkins therefore reads (depends on) data from mesh.layers[*].parts[*].insets and writes mesh.layers[n].parts[*].skin_parts
- */
+        
 void generateSkins(int layerNr, SliceMeshStorage& mesh, int downSkinCount, int upSkinCount, int wall_line_count, int innermost_wall_line_width, int insetCount, bool no_small_gaps_heuristic)
 {
     generateSkinAreas(layerNr, mesh, innermost_wall_line_width, downSkinCount, upSkinCount, wall_line_count, no_small_gaps_heuristic);
@@ -32,12 +23,6 @@ void generateSkins(int layerNr, SliceMeshStorage& mesh, int downSkinCount, int u
     }
 }
 
-/*
- * This function is executed in a parallel region based on layer_nr.
- * When modifying make sure any changes does not introduce data races.
- *
- * generateSkinAreas reads data from mesh.layers[*].parts[*].insets and writes to mesh.layers[n].parts[*].skin_parts
- */
 void generateSkinAreas(int layer_nr, SliceMeshStorage& mesh, const int innermost_wall_line_width, int downSkinCount, int upSkinCount, int wall_line_count, bool no_small_gaps_heuristic)
 {
     SliceLayer& layer = mesh.layers[layer_nr];
@@ -139,12 +124,7 @@ void generateSkinAreas(int layer_nr, SliceMeshStorage& mesh, const int innermost
     }
 }
 
-/*
- * This function is executed in a parallel region based on layer_nr.
- * When modifying make sure any changes does not introduce data races.
- *
- * generateSkinInsets only read/writes the skin_parts from the current layer.
- */
+
 void generateSkinInsets(SliceLayerPart* part, const int wall_line_width, int insetCount)
 {
     if (insetCount == 0)
@@ -177,12 +157,6 @@ void generateSkinInsets(SliceLayerPart* part, const int wall_line_width, int ins
     }
 }
 
-/*
- * This function is executed in a parallel region based on layer_nr.
- * When modifying make sure any changes does not introduce data races.
- *
- * generateInfill read mesh.layers[n].parts[*].{insets,skin_parts,boundingBox} and write mesh.layers[n].parts[*].infill_area
- */
 void generateInfill(int layerNr, SliceMeshStorage& mesh, const int innermost_wall_line_width, int infill_skin_overlap, int wall_line_count)
 {
     SliceLayer& layer = mesh.layers[layerNr];

src/sliceDataStorage.cpp

@@ -35,7 +35,7 @@ void SliceLayer::getOutlines(Polygons& result, bool external_polys_only) const
     {
         if (external_polys_only)
         {
-            result.add(part.outline.outerPolygon());
+            result.add(const_cast<SliceLayerPart&>(part).outline.outerPolygon()); // TODO: make a const version of outerPolygon()
         }
         else 
         {
@@ -57,12 +57,12 @@ void SliceLayer::getSecondOrInnermostWalls(Polygons& layer_walls) const
     {
         // we want the 2nd inner walls
         if (part.insets.size() >= 2) {
-            layer_walls.add(part.insets[1]);
+            layer_walls.add(const_cast<SliceLayerPart&>(part).insets[1]); // TODO const cast!
             continue;
         }
         // but we'll also take the inner wall if the 2nd doesn't exist
         if (part.insets.size() == 1) {
-            layer_walls.add(part.insets[0]);
+            layer_walls.add(const_cast<SliceLayerPart&>(part).insets[0]); // TODO const cast!
             continue;
         }
         // offset_from_outlines was so large that it completely destroyed our isle,
@@ -87,11 +87,38 @@ std::vector<RetractionConfig> SliceDataStorage::initializeRetractionConfigs()
     return ret;
 }
 
+std::vector<GCodePathConfig> SliceDataStorage::initializeTravelConfigs()
+{
+    std::vector<GCodePathConfig> ret;
+    for (int extruder = 0; extruder < meshgroup->getExtruderCount(); extruder++)
+    {
+        travel_config_per_extruder.emplace_back(PrintFeatureType::MoveCombing);
+    }
+    return ret;
+}
+
+std::vector<GCodePathConfig> SliceDataStorage::initializeSkirtBrimConfigs()
+{
+    std::vector<GCodePathConfig> ret;
+    for (int extruder = 0; extruder < meshgroup->getExtruderCount(); extruder++)
+    {
+        skirt_brim_config.emplace_back(PrintFeatureType::SkirtBrim);
+    }
+    return ret;
+}
+
 SliceDataStorage::SliceDataStorage(MeshGroup* meshgroup) : SettingsMessenger(meshgroup),
     meshgroup(meshgroup != nullptr ? meshgroup : new MeshGroup(FffProcessor::getInstance())), //If no mesh group is provided, we roll our own.
     print_layer_count(0),
     retraction_config_per_extruder(initializeRetractionConfigs()),
     extruder_switch_retraction_config_per_extruder(initializeRetractionConfigs()),
+    travel_config_per_extruder(initializeTravelConfigs()),
+    skirt_brim_config(initializeSkirtBrimConfigs()),
+    raft_base_config(PrintFeatureType::SupportInterface),
+    raft_interface_config(PrintFeatureType::Support),
+    raft_surface_config(PrintFeatureType::SupportInterface),
+    support_config(PrintFeatureType::Support),
+    support_skin_config(PrintFeatureType::SupportInterface),
     max_print_height_second_to_last_extruder(-1),
     primeTower(*this)
 {
@@ -136,7 +163,7 @@ Polygons SliceDataStorage::getLayerOutlines(int layer_nr, bool include_helper_pa
                 }
                 const SliceLayer& layer = mesh.layers[layer_nr];
                 layer.getOutlines(total, external_polys_only);
-                if (mesh.getSettingAsSurfaceMode("magic_mesh_surface_mode") != ESurfaceMode::NORMAL)
+                if (const_cast<SliceMeshStorage&>(mesh).getSettingAsSurfaceMode("magic_mesh_surface_mode") != ESurfaceMode::NORMAL) // TODO: make all getSetting functions const??
                 {
                     total = total.unionPolygons(layer.openPolyLines.offsetPolyLine(100));
                 }
@@ -180,7 +207,7 @@ Polygons SliceDataStorage::getLayerSecondOrInnermostWalls(int layer_nr, bool inc
             {
                 const SliceLayer& layer = mesh.layers[layer_nr];
                 layer.getSecondOrInnermostWalls(total);
-                if (mesh.getSettingAsSurfaceMode("magic_mesh_surface_mode") != ESurfaceMode::NORMAL)
+                if (const_cast<SliceMeshStorage&>(mesh).getSettingAsSurfaceMode("magic_mesh_surface_mode") != ESurfaceMode::NORMAL) // TODO: make getSetting const? make settings.setting_values mapping mutable??
                 {
                     total = total.unionPolygons(layer.openPolyLines.offsetPolyLine(100));
                 }

src/sliceDataStorage.h

@@ -8,9 +8,10 @@
 #include "utils/NoCopy.h"
 #include "utils/AABB.h"
 #include "mesh.h"
+#include "gcodePlanner.h"
 #include "MeshGroup.h"
 #include "PrimeTower.h"
-#include "gcodeExport.h" // CoastingConfig
+#include "GCodePathConfig.h"
 
 namespace cura 
 {
@@ -73,6 +74,8 @@ public:
      * \return the own infill area
      */
     Polygons& getOwnInfillArea();
+
+    std::vector<std::pair<PolygonsPart, double>> spaghetti_infill_volumes; //!< For each filling volume on this layer, the area within which to fill and the total volume to fill over the area
 };
 
 /*!
@@ -137,11 +140,7 @@ public:
 
     std::vector<SupportLayer> supportLayers;
 
-    SupportStorage()
-    : generated(false)
-    , layer_nr_max_filled_layer(-1)
-    {
-    }
+    SupportStorage() : generated(false), layer_nr_max_filled_layer(-1) { }
     ~SupportStorage(){ supportLayers.clear(); }
 };
 /******************/
@@ -155,14 +154,27 @@ public:
 
     int layer_nr_max_filled_layer; //!< the layer number of the uppermost layer with content (modified while infill meshes are processed)
 
+    GCodePathConfig inset0_config;
+    GCodePathConfig insetX_config;
+    GCodePathConfig skin_config;
+    GCodePathConfig perimeter_gap_config;
+    std::vector<GCodePathConfig> infill_config;
+
     SubDivCube* base_subdiv_cube;
 
     SliceMeshStorage(SettingsBaseVirtual* settings, unsigned int slice_layer_count)
     : SettingsMessenger(settings)
     , layer_nr_max_filled_layer(0)
+    , inset0_config(PrintFeatureType::OuterWall)
+    , insetX_config(PrintFeatureType::InnerWall)
+    , skin_config(PrintFeatureType::Skin)
+    , perimeter_gap_config(PrintFeatureType::Skin)
     , base_subdiv_cube(nullptr)
     {
         layers.resize(slice_layer_count);
+        infill_config.reserve(MAX_INFILL_COMBINE);
+        for(int n=0; n<MAX_INFILL_COMBINE; n++)
+            infill_config.emplace_back(PrintFeatureType::Infill);
     }
 
     virtual ~SliceMeshStorage();
@@ -181,8 +193,18 @@ public:
     std::vector<RetractionConfig> retraction_config_per_extruder; //!< Retraction config per extruder.
     std::vector<RetractionConfig> extruder_switch_retraction_config_per_extruder; //!< Retraction config per extruder for when performing an extruder switch
 
+    std::vector<GCodePathConfig> travel_config_per_extruder; //!< The config used for travel moves (only speed is set!)
+
+    std::vector<GCodePathConfig> skirt_brim_config; //!< Configuration for skirt and brim per extruder.
     std::vector<CoastingConfig> coasting_config; //!< coasting config per extruder
 
+    GCodePathConfig raft_base_config;
+    GCodePathConfig raft_interface_config;
+    GCodePathConfig raft_surface_config;
+
+    GCodePathConfig support_config;
+    GCodePathConfig support_skin_config; //!< The config to use to print the dense roofs and bottoms of support
+
     SupportStorage support;
 
     Polygons skirt_brim[MAX_EXTRUDERS]; //!< Skirt and brim polygons per extruder, ordered from inner to outer polygons.
@@ -197,6 +219,21 @@ public:
     std::vector<Polygons> oozeShield;        //oozeShield per layer
     Polygons draft_protection_shield; //!< The polygons for a heightened skirt which protects from warping by gusts of wind and acts as a heated chamber.
 
+    /*!
+     * Construct the initial retraction_config_per_extruder
+     */
+    std::vector<RetractionConfig> initializeRetractionConfigs();
+
+    /*!
+     * Construct the initial travel_config_per_extruder
+     */
+    std::vector<GCodePathConfig> initializeTravelConfigs();
+
+    /*!
+     * Construct the initial skirt & brim configurations for each extruder.
+     */
+    std::vector<GCodePathConfig> initializeSkirtBrimConfigs();
+
     /*!
      * \brief Creates a new slice data storage that stores the slice data of the
      * specified mesh group.
@@ -246,12 +283,6 @@ public:
      * \return a vector of bools indicating whether the extruder with corresponding index is used in this layer.
      */
     std::vector<bool> getExtrudersUsed(int layer_nr) const;
-
-private:
-    /*!
-     * Construct the retraction_config_per_extruder
-     */
-    std::vector<RetractionConfig> initializeRetractionConfigs();
 };
 
 }//namespace cura

src/slicer.cpp

@@ -216,7 +216,7 @@ SlicerLayer::findPossibleStitches(
     //   insert the starts of the polylines).
     for(unsigned int polyline_0_idx = 0; polyline_0_idx < open_polylines.size(); polyline_0_idx++)
     {
-        ConstPolygonRef polyline_0 = open_polylines[polyline_0_idx];
+        const PolygonRef polyline_0 = open_polylines[polyline_0_idx];
 
         if (polyline_0.size() < 1) continue;
 
@@ -231,7 +231,7 @@ SlicerLayer::findPossibleStitches(
     {
         for(unsigned int polyline_0_idx = 0; polyline_0_idx < open_polylines.size(); polyline_0_idx++)
         {
-            ConstPolygonRef polyline_0 = open_polylines[polyline_0_idx];
+            const PolygonRef polyline_0 = open_polylines[polyline_0_idx];
 
             if (polyline_0.size() < 1) continue;
 
@@ -245,7 +245,7 @@ SlicerLayer::findPossibleStitches(
     // search for nearby end points
     for(unsigned int polyline_1_idx = 0; polyline_1_idx < open_polylines.size(); polyline_1_idx++)
     {
-        ConstPolygonRef polyline_1 = open_polylines[polyline_1_idx];
+        const PolygonRef polyline_1 = open_polylines[polyline_1_idx];
 
         if (polyline_1.size() < 1) continue;
 
@@ -887,14 +887,10 @@ Slicer::Slicer(Mesh* mesh, int initial, int thickness, int slice_layer_count, bo
         }
     }
     log("slice of mesh took %.3f seconds\n",slice_timer.restart());
-
-    std::vector<SlicerLayer>& layers_ref = layers; // force layers not to be copied into the threads
-#pragma omp parallel for default(none) shared(mesh,layers_ref) firstprivate(keep_none_closed, extensive_stitching)
-    for(unsigned int layer_nr=0; layer_nr<layers_ref.size(); layer_nr++)
+    for(unsigned int layer_nr=0; layer_nr<layers.size(); layer_nr++)
     {
-        layers_ref[layer_nr].makePolygons(mesh, keep_none_closed, extensive_stitching);
+        layers[layer_nr].makePolygons(mesh, keep_none_closed, extensive_stitching);
     }
-
     mesh->expandXY(mesh->getSettingInMicrons("xy_offset"));
     log("slice make polygons took %.3f seconds\n",slice_timer.restart());
 }

src/support.cpp

@@ -165,7 +165,6 @@ void AreaSupport::generateSupportAreas(SliceDataStorage& storage, unsigned int m
     const int supportTowerDiameter = mesh.getSettingInMicrons("support_tower_diameter");
     const int supportMinAreaSqrt = mesh.getSettingInMicrons("support_minimal_diameter");
     const double supportTowerRoofAngle = mesh.getSettingInAngleRadians("support_tower_roof_angle");
-    const bool use_towers = mesh.getSettingBoolean("support_use_towers") && supportMinAreaSqrt > 0;
 
     const int layerThickness = storage.getSettingInMicrons("layer_height");
     const int supportXYDistance = mesh.getSettingInMicrons("support_xy_distance");
@@ -235,10 +234,7 @@ void AreaSupport::generateSupportAreas(SliceDataStorage& storage, unsigned int m
         
     
     std::vector<std::pair<int, std::vector<Polygons>>> overhang_points; // stores overhang_points along with the layer index at which the overhang point occurs
-    if (use_towers)
-    {
-        AreaSupport::detectOverhangPoints(storage, mesh, overhang_points, layer_count, supportMinAreaSqrt);
-    }
+    AreaSupport::detectOverhangPoints(storage, mesh, overhang_points, layer_count, supportMinAreaSqrt);
 
     std::deque<std::pair<Polygons, Polygons>> basic_and_full_overhang_above;
     for (unsigned int layer_idx = support_layer_count - 1; layer_idx != support_layer_count - 1 - layerZdistanceTop ; layer_idx--)
@@ -268,7 +264,7 @@ void AreaSupport::generateSupportAreas(SliceDataStorage& storage, unsigned int m
             supportLayer_this = supportLayer_this.offset(extension_offset);
         }
 
-        if (use_towers)
+        if (supportMinAreaSqrt > 0)
         {
             // handle straight walls
             AreaSupport::handleWallStruts(supportLayer_this, supportMinAreaSqrt, supportTowerDiameter);

src/utils/AABB.cpp

@@ -24,7 +24,7 @@ AABB::AABB(const Polygons& polys)
     calculate(polys);
 }
 
-AABB::AABB(ConstPolygonRef poly)
+AABB::AABB(const PolygonRef poly)
 : min(POINT_MAX, POINT_MAX), max(POINT_MIN, POINT_MIN)
 {
     calculate(poly);
@@ -43,7 +43,7 @@ void AABB::calculate(const Polygons& polys)
     }
 }
 
-void AABB::calculate(ConstPolygonRef poly)
+void AABB::calculate(const PolygonRef poly)
 {
     min = Point(POINT_MAX, POINT_MAX);
     max = Point(POINT_MIN, POINT_MIN);

src/utils/AABB.h

@@ -20,10 +20,10 @@ public:
     AABB(); //!< initializes with invalid min and max
     AABB(Point& min, Point& max); //!< initializes with given min and max
     AABB(const Polygons& polys); //!< Computes the boundary box for the given polygons
-    AABB(ConstPolygonRef poly); //!< Computes the boundary box for the given polygons
+    AABB(const PolygonRef poly); //!< Computes the boundary box for the given polygons
 
     void calculate(const Polygons& polys); //!< Calculates the aabb for the given polygons (throws away old min and max data of this aabb)
-    void calculate(ConstPolygonRef poly); //!< Calculates the aabb for the given polygon (throws away old min and max data of this aabb)
+    void calculate(const PolygonRef poly); //!< Calculates the aabb for the given polygon (throws away old min and max data of this aabb)
 
     /*!
      * Check whether this aabb overlaps with another.

src/utils/ListPolyIt.cpp

@@ -10,21 +10,21 @@ namespace cura
 {
 
 
-void ListPolyIt::convertPolygonsToLists(const Polygons& polys, ListPolygons& result)
+void ListPolyIt::convertPolygonsToLists(Polygons& polys, ListPolygons& result)
 {
-    for (ConstPolygonRef poly : polys)
+    for (PolygonRef poly : polys)
     {
         result.emplace_back();
         convertPolygonToList(poly, result.back());
     }
 }
 
-void ListPolyIt::convertPolygonToList(ConstPolygonRef poly, ListPolygon& result)
+void ListPolyIt::convertPolygonToList(PolygonRef poly, ListPolygon& result)
 {
 #ifdef DEBUG
     Point last = poly.back();
 #endif // DEBUG
-    for (const Point& p : poly)
+    for (Point& p : poly) 
     {
         result.push_back(p);
 #ifdef DEBUG
@@ -39,7 +39,7 @@ void ListPolyIt::convertPolygonToList(ConstPolygonRef poly, ListPolygon& result)
 }
 
 
-void ListPolyIt::convertListPolygonsToPolygons(const ListPolygons& list_polygons, Polygons& polygons)
+void ListPolyIt::convertListPolygonsToPolygons(ListPolygons& list_polygons, Polygons& polygons)
 {
     for (unsigned int poly_idx = 0; poly_idx < polygons.size(); poly_idx++)
     {
@@ -48,9 +48,9 @@ void ListPolyIt::convertListPolygonsToPolygons(const ListPolygons& list_polygons
     }
 }
 
-void ListPolyIt::convertListPolygonToPolygon(const ListPolygon& list_polygon, PolygonRef polygon)
+void ListPolyIt::convertListPolygonToPolygon(ListPolygon& list_polygon, PolygonRef polygon)
 {
-    for (const Point& p : list_polygon)
+    for (Point& p : list_polygon)
     {
         polygon.add(p);
     }

src/utils/ListPolyIt.h

@@ -94,28 +94,28 @@ public:
      * \param polys The polygons to convert
      * \param result The converted polygons
      */
-    static void convertPolygonsToLists(const Polygons& polys, ListPolygons& result);
+    static void convertPolygonsToLists(Polygons& polys, ListPolygons& result);
     /*!
      * Convert Polygons to ListPolygons
      * 
      * \param polys The polygons to convert
      * \param result The converted polygons
      */
-    static void convertPolygonToList(ConstPolygonRef poly, ListPolygon& result);
+    static void convertPolygonToList(PolygonRef poly, ListPolygon& result);
     /*!
      * Convert ListPolygons to Polygons
      * 
      * \param list_polygons The polygons to convert
      * \param polygons The converted polygons
      */
-    static void convertListPolygonsToPolygons(const ListPolygons& list_polygons, Polygons& polygons);
+    static void convertListPolygonsToPolygons(ListPolygons& list_polygons, Polygons& polygons);
     /*!
      * Convert ListPolygons to Polygons
      * 
      * \param list_polygons The polygons to convert
      * \param polygons The converted polygons
      */
-    static void convertListPolygonToPolygon(const ListPolygon& list_polygon, PolygonRef polygon);
+    static void convertListPolygonToPolygon(ListPolygon& list_polygon, PolygonRef polygon);
 
     /*!
      * Insert a point into a ListPolygon if it's not a duplicate of the point before or the point after.

src/utils/PolygonsPointIndex.h

@@ -46,7 +46,7 @@ public:
     /*!
      * Get the polygon to which this PolygonsPointIndex refers
      */
-    ConstPolygonRef getPolygon() const
+    const PolygonRef getPolygon() const
     {
         return (*polygons)[poly_idx];
     }

src/utils/SVG.h

@@ -93,8 +93,9 @@ public:
         {
             for(unsigned int j=0;j<parts.size();j++)
             {
+                Polygon poly = parts[j];
                 fprintf(out, "<polygon points=\"");
-                for (Point& p : parts[j])
+                for(Point& p : poly)
                 {
                     Point fp = transform(p);
                     fprintf(out, "%lli,%lli ", fp.X, fp.Y);
@@ -129,9 +130,9 @@ public:
         }
     }
 
-    void writePoints(ConstPolygonRef poly, bool write_coords=false, int size = 5, Color color = Color::BLACK)
+    void writePoints(PolygonRef poly, bool write_coords=false, int size = 5, Color color = Color::BLACK)
     {
-        for (const Point& p : poly)
+        for (Point& p : poly)
         {
             writePoint(p, write_coords, size, color);
         }
@@ -208,12 +209,12 @@ public:
     }
     void writePolygons(const Polygons& polys, Color color = Color::BLACK)
     {
-        for (ConstPolygonRef poly : polys)
+        for (const PolygonRef poly : const_cast<Polygons&>(polys))
         {
             writePolygon(poly, color);
         }
     }
-    void writePolygon(ConstPolygonRef poly, Color color = Color::BLACK)
+    void writePolygon(const PolygonRef poly, Color color = Color::BLACK)
     {
         Point p0 = poly.back();
         for (Point p1 : poly)

src/utils/polygon.cpp

@@ -8,9 +8,9 @@
 namespace cura 
 {
 
-bool ConstPolygonRef::shorterThan(int64_t check_length) const
+bool PolygonRef::shorterThan(int64_t check_length) const
 {
-    const ConstPolygonRef& polygon = *this;
+    const PolygonRef& polygon = *this;
     const Point* p0 = &polygon.back();
     int64_t length = 0;
     for (const Point& p1 : polygon)
@@ -25,9 +25,9 @@ bool ConstPolygonRef::shorterThan(int64_t check_length) const
     return true;
 }
 
-bool ConstPolygonRef::_inside(Point p, bool border_result) const
+bool PolygonRef::_inside(Point p, bool border_result) const
 {
-    const ConstPolygonRef thiss = *this;
+    PolygonRef thiss = *this;
     if (size() < 1)
     {
         return false;
@@ -190,6 +190,22 @@ unsigned int Polygons::findInside(Point p, bool border_result)
     return ret;
 }
 
+int64_t Polygons::polyLineLength() const
+{
+    int64_t length = 0;
+    for (unsigned int poly_idx = 0; poly_idx < paths.size(); poly_idx++)
+    {
+        Point p0 = paths[poly_idx][0];
+        for (unsigned int point_idx = 1; point_idx < paths[poly_idx].size(); point_idx++)
+        {
+            Point p1 = paths[poly_idx][point_idx];
+            length += vSize(p0 - p1);
+            p0 = p1;
+        }
+    }
+    return length;
+}
+
 Polygons Polygons::offset(int distance, ClipperLib::JoinType join_type, double miter_limit) const
 {
     Polygons ret;
@@ -200,11 +216,11 @@ Polygons Polygons::offset(int distance, ClipperLib::JoinType join_type, double m
     return ret;
 }
 
-Polygons ConstPolygonRef::offset(int distance, ClipperLib::JoinType join_type, double miter_limit) const
+Polygons PolygonRef::offset(int distance, ClipperLib::JoinType joinType, double miter_limit) const
 {
     Polygons ret;
     ClipperLib::ClipperOffset clipper(miter_limit, 10.0);
-    clipper.AddPath(*path, join_type, ClipperLib::etClosedPolygon);
+    clipper.AddPath(*path, joinType, ClipperLib::etClosedPolygon);
     clipper.MiterLimit = miter_limit;
     clipper.Execute(ret.paths, distance);
     return ret;
@@ -521,7 +537,7 @@ void Polygons::removeEmptyHoles_processPolyTreeNode(const ClipperLib::PolyNode&
     }
 }
 
-bool ConstPolygonRef::smooth_corner_complex(ListPolygon& poly, const Point p1, ListPolyIt& p0_it, ListPolyIt& p2_it, const int64_t shortcut_length)
+bool PolygonRef::smooth_corner_complex(ListPolygon& poly, const Point p1, ListPolyIt& p0_it, ListPolyIt& p2_it, const int64_t shortcut_length)
 {
     // walk away from the corner until the shortcut > shortcut_length or it would smooth a piece inward
     // - walk in both directions untill shortcut > shortcut_length 
@@ -703,7 +719,7 @@ bool ConstPolygonRef::smooth_corner_complex(ListPolygon& poly, const Point p1, L
     return false;
 }
 
-void ConstPolygonRef::smooth_outward_step(const Point p1, const int64_t shortcut_length2, ListPolyIt& p0_it, ListPolyIt& p2_it, bool& forward_is_blocked, bool& backward_is_blocked, bool& forward_is_too_far, bool& backward_is_too_far)
+void PolygonRef::smooth_outward_step(const Point p1, const int64_t shortcut_length2, ListPolyIt& p0_it, ListPolyIt& p2_it, bool& forward_is_blocked, bool& backward_is_blocked, bool& forward_is_too_far, bool& backward_is_too_far)
 {
     const bool forward_has_converged = forward_is_blocked || forward_is_too_far;
     const bool backward_has_converged = backward_is_blocked || backward_is_too_far;
@@ -759,7 +775,7 @@ void ConstPolygonRef::smooth_outward_step(const Point p1, const int64_t shortcut
     }
 }
 
-void ConstPolygonRef::smooth_corner_simple(ListPolygon& poly, const Point p0, const Point p1, const Point p2, const ListPolyIt p0_it, const ListPolyIt p1_it, const ListPolyIt p2_it, const Point v10, const Point v12, const Point v02, const int64_t shortcut_length, float cos_angle)
+void PolygonRef::smooth_corner_simple(ListPolygon& poly, const Point p0, const Point p1, const Point p2, const ListPolyIt p0_it, const ListPolyIt p1_it, const ListPolyIt p2_it, const Point v10, const Point v12, const Point v02, const int64_t shortcut_length, float cos_angle)
 {
     //  1----b---->2
     //  ^   /
@@ -849,7 +865,7 @@ void ConstPolygonRef::smooth_corner_simple(ListPolygon& poly, const Point p0, co
     }
 }
 
-void ConstPolygonRef::smooth_outward(float min_angle, int shortcut_length, PolygonRef result) const
+void PolygonRef::smooth_outward(float min_angle, int shortcut_length, PolygonRef result) const
 {
 // example of smoothed out corner:
 //
@@ -952,8 +968,7 @@ Polygons Polygons::smooth_outward(float max_angle, int shortcut_length)
     return ret;
 }
 
-
-void ConstPolygonRef::smooth(int remove_length, PolygonRef result) const
+void PolygonRef::smooth(int remove_length, PolygonRef result)
 {
 // a typical zigzag with the middle part to be removed by removing (1) :
 //
@@ -968,7 +983,7 @@ void ConstPolygonRef::smooth(int remove_length, PolygonRef result) const
 //          |
 //          |
 //          0
-    const ConstPolygonRef& thiss = *path;
+    PolygonRef& thiss = *this;
     ClipperLib::Path* poly = result.path;
     if (size() > 0)
     {
@@ -1037,12 +1052,12 @@ void ConstPolygonRef::smooth(int remove_length, PolygonRef result) const
     }
 }
 
-Polygons Polygons::smooth(int remove_length) const
+Polygons Polygons::smooth(int remove_length)
 {
     Polygons ret;
     for (unsigned int p = 0; p < size(); p++)
     {
-        ConstPolygonRef poly(paths[p]);
+        PolygonRef poly(paths[p]);
         if (poly.size() < 3)
         {
             continue;
@@ -1062,23 +1077,23 @@ Polygons Polygons::smooth(int remove_length) const
     return ret;
 }
 
-void ConstPolygonRef::smooth2(int remove_length, PolygonRef result) const
+void PolygonRef::smooth2(int remove_length, PolygonRef result)
 {
-    const ConstPolygonRef& thiss = *this;
+    PolygonRef& thiss = *this;
     ClipperLib::Path* poly = result.path;
-    if (thiss.size() > 0)
+    if (size() > 0)
     {
         poly->push_back(thiss[0]);
     }
-    for (unsigned int poly_idx = 1; poly_idx < thiss.size(); poly_idx++)
+    for (unsigned int poly_idx = 1; poly_idx < size(); poly_idx++)
     {
-        const Point& last = thiss[poly_idx - 1];
-        const Point& now = thiss[poly_idx];
-        const Point& next = thiss[(poly_idx + 1) % thiss.size()];
-        if (shorterThen(last - now, remove_length) && shorterThen(now - next, remove_length))
+        Point& last = thiss[poly_idx - 1];
+        Point& now = thiss[poly_idx];
+        Point& next = thiss[(poly_idx + 1) % size()];
+        if (shorterThen(last - now, remove_length) && shorterThen(now - next, remove_length)) 
         {
             poly_idx++; // skip the next line piece (dont escalate the removal of edges)
-            if (poly_idx < thiss.size())
+            if (poly_idx < size())
             {
                 poly->push_back(thiss[poly_idx]);
             }
@@ -1090,12 +1105,12 @@ void ConstPolygonRef::smooth2(int remove_length, PolygonRef result) const
     }
 }
 
-Polygons Polygons::smooth2(int remove_length, int min_area) const
+Polygons Polygons::smooth2(int remove_length, int min_area)
 {
     Polygons ret;
     for (unsigned int p = 0; p < size(); p++)
     {
-        ConstPolygonRef poly(paths[p]);
+        PolygonRef poly(paths[p]);
         if (poly.size() == 0)
         {
             continue;
@@ -1117,6 +1132,17 @@ Polygons Polygons::smooth2(int remove_length, int min_area) const
     return ret;
 }
 
+double PolygonsPart::area() const
+{
+    double area = 0;
+    for (unsigned int poly_idx = 0; poly_idx < size(); poly_idx++)
+    {
+        area += operator[](poly_idx).area();
+        // note: holes have negative area
+    }
+    return area;
+}
+
 std::vector<PolygonsPart> Polygons::splitIntoParts(bool unionAll) const
 {
     std::vector<PolygonsPart> ret;
@@ -1148,14 +1174,14 @@ void Polygons::splitIntoParts_processPolyTreeNode(ClipperLib::PolyNode* node, st
     }
 }
 
-unsigned int PartsView::getPartContaining(unsigned int poly_idx, unsigned int* boundary_poly_idx) const
+unsigned int PartsView::getPartContaining(unsigned int poly_idx, unsigned int* boundary_poly_idx) 
 {
-    const PartsView& partsView = *this;
+    PartsView& partsView = *this;
     for (unsigned int part_idx_now = 0; part_idx_now < partsView.size(); part_idx_now++)
     {
-        const std::vector<unsigned int>& partView = partsView[part_idx_now];
+        std::vector<unsigned int>& partView = partsView[part_idx_now];
         if (partView.size() == 0) { continue; }
-        std::vector<unsigned int>::const_iterator result = std::find(partView.begin(), partView.end(), poly_idx);
+        std::vector<unsigned int>::iterator result = std::find(partView.begin(), partView.end(), poly_idx);
         if (result != partView.end()) 
         { 
             if (boundary_poly_idx) { *boundary_poly_idx = partView[0]; }
@@ -1179,7 +1205,7 @@ PolygonsPart PartsView::assemblePart(unsigned int part_idx) const
     return ret;
 }
 
-PolygonsPart PartsView::assemblePartContaining(unsigned int poly_idx, unsigned int* boundary_poly_idx) const
+PolygonsPart PartsView::assemblePartContaining(unsigned int poly_idx, unsigned int* boundary_poly_idx) 
 {
     PolygonsPart ret;
     unsigned int part_idx = getPartContaining(poly_idx, boundary_poly_idx);
@@ -1216,7 +1242,7 @@ void Polygons::splitIntoPartsView_processPolyTreeNode(PartsView& partsView, Poly
         partsView.emplace_back();
         unsigned int pos = partsView.size() - 1;
         partsView[pos].push_back(reordered.size());
-        reordered.add(child->Contour); //TODO: should this steal the internal representation for speed?
+        reordered.add(child->Contour);
         for(int i = 0; i < child->ChildCount(); i++)
         {
             partsView[pos].push_back(reordered.size());

src/utils/polygon.h

@@ -27,8 +27,6 @@ namespace cura {
 
 class PartsView;
 class Polygons;
-class Polygon;
-class PolygonRef;
 
 class ListPolyIt;
 
@@ -38,60 +36,31 @@ typedef std::vector<ListPolygon> ListPolygons; //!< Polygons represented by a ve
 const static int clipper_init = (0);
 #define NO_INDEX (std::numeric_limits<unsigned int>::max())
 
-class ConstPolygonRef
+class PolygonRef
 {
-    friend class Polygons;
-    friend class Polygon;
-    friend class PolygonRef;
-protected:
     ClipperLib::Path* path;
-    ConstPolygonRef()
+    PolygonRef()
     : path(nullptr)
     {}
 public:
-    ConstPolygonRef(const ClipperLib::Path& polygon)
-    : path(const_cast<ClipperLib::Path*>(&polygon))
+    PolygonRef(ClipperLib::Path& polygon)
+    : path(&polygon)
     {}
-
-    bool operator==(ConstPolygonRef& other) const =delete;
-
-// needed in std::optional<ConstPolygonRef>
-//     ConstPolygonRef& operator=(const ConstPolygonRef& other) =delete;
-    ConstPolygonRef& operator=(const ConstPolygonRef& other)
-    {
-        path = other.path;
-        return *this;
-    }
-
+    
     unsigned int size() const
     {
         return path->size();
     }
 
-    const Point& operator[] (unsigned int index) const
+    Point& operator[] (unsigned int index) const
     {
-        POLY_ASSERT(index < size());
+        POLY_ASSERT(index < size() && index <= std::numeric_limits<int>::max());
         return (*path)[index];
     }
 
-    const ClipperLib::Path& operator*() const
+    void* data()
     {
-        return *path;
-    }
-
-    ClipperLib::Path::const_iterator begin() const
-    {
-        return path->begin();
-    }
-
-    ClipperLib::Path::const_iterator end() const
-    {
-        return path->end();
-    }
-
-    ClipperLib::Path::const_reference back() const
-    {
-        return path->back();
+        return path->data();
     }
 
     const void* data() const
@@ -99,10 +68,37 @@ public:
         return path->data();
     }
 
+    void add(const Point p)
+    {
+        path->push_back(p);
+    }
+
+    PolygonRef& operator=(const PolygonRef& other) { path = other.path; return *this; }
+
+    bool operator==(const PolygonRef& other) const =delete;
+
+    ClipperLib::Path& operator*() { return *path; }
+    
+    template <typename... Args>
+    void emplace_back(Args&&... args)
+    {
+        path->emplace_back(args...);
+    }
+
+    void remove(unsigned int index)
+    {
+        POLY_ASSERT(index < size() && index <= std::numeric_limits<int>::max());
+        path->erase(path->begin() + index);
+    }
+
+    void clear()
+    {
+        path->clear();
+    }
 
     /*!
      * On Y-axis positive upward displays, Orientation will return true if the polygon's orientation is counter-clockwise.
-     *
+     * 
      * from http://www.angusj.com/delphi/clipper/documentation/Docs/Units/ClipperLib/Functions/Orientation.htm
      */
     bool orientation() const
@@ -110,6 +106,11 @@ public:
         return ClipperLib::Orientation(*path);
     }
 
+    void reverse()
+    {
+        ClipperLib::ReversePath(*path);
+    }
+
     Polygons offset(int distance, ClipperLib::JoinType joinType = ClipperLib::jtMiter, double miter_limit = 1.2) const;
 
     int64_t polygonLength() const
@@ -124,7 +125,7 @@ public:
         }
         return length;
     }
-
+    
     bool shorterThan(int64_t check_length) const;
 
     Point min() const
@@ -137,7 +138,7 @@ public:
         }
         return ret;
     }
-
+    
     Point max() const
     {
         Point ret = Point(POINT_MIN, POINT_MIN);
@@ -153,6 +154,19 @@ public:
     {
         return ClipperLib::Area(*path);
     }
+    
+    /*!
+     * Translate the whole polygon in some direction.
+     * 
+     * \param translation The direction in which to move the polygon
+     */
+    void translate(Point translation)
+    {
+        for (Point& p : *this)
+        {
+            p += translation;
+        }
+    }
 
     Point centerOfMass() const
     {
@@ -169,14 +183,14 @@ public:
         }
 
         double area = Area(*path);
-
+        
         x = x / 6 / area;
         y = y / 6 / area;
 
         return Point(x, y);
     }
 
-    Point closestPointTo(Point p) const
+    Point closestPointTo(Point p)
     {
         Point ret = p;
         float bestDist = FLT_MAX;
@@ -191,7 +205,7 @@ public:
         }
         return ret;
     }
-
+    
     /*!
      * Check if we are inside the polygon. We do this by tracing from the point towards the positive X direction,
      * every line we cross increments the crossings counter. If we have an even number of crossings then we are not inside the polygon.
@@ -227,7 +241,7 @@ public:
         }
         return res == 1;
     }
-
+    
     /*!
      * Smooth out small perpendicular segments and store the result in \p result.
      * Smoothing is performed by removing the inner most vertex of a line segment smaller than \p remove_length
@@ -239,7 +253,7 @@ public:
      * \param remove_length The length of the largest segment removed
      * \param result (output) The result polygon, assumed to be empty
      */
-    void smooth(int remove_length, PolygonRef result) const;
+    void smooth(int remove_length, PolygonRef result);
 
     /*!
      * Smooth out sharp inner corners, by taking a shortcut which bypasses the corner
@@ -257,8 +271,51 @@ public:
      * \param remove_length The length of the largest segment removed
      * \param result (output) The result polygon, assumed to be empty
      */
-    void smooth2(int remove_length, PolygonRef result) const;
+    void smooth2(int remove_length, PolygonRef result);
 
+    /*! 
+     * Removes consecutive line segments with same orientation and changes this polygon.
+     * 
+     * Removes verts which are connected to line segments which are both too small.
+     * Removes verts which detour from a direct line from the previous and next vert by a too small amount.
+     * 
+     * \param smallest_line_segment_squared maximal squared length of removed line segments
+     * \param allowed_error_distance_squared The square of the distance of the middle point to the line segment of the consecutive and previous point for which the middle point is removed
+     */
+    void simplify(int smallest_line_segment_squared = 100, int allowed_error_distance_squared = 25);
+
+    void pop_back()
+    { 
+        path->pop_back();
+    }
+    
+    ClipperLib::Path::reference back() const
+    {
+        return path->back();
+    }
+    
+    ClipperLib::Path::iterator begin()
+    {
+        return path->begin();
+    }
+
+    ClipperLib::Path::iterator end()
+    {
+        return path->end();
+    }
+
+    ClipperLib::Path::const_iterator begin() const
+    {
+        return path->begin();
+    }
+
+    ClipperLib::Path::const_iterator end() const
+    {
+        return path->end();
+    }
+
+    friend class Polygons;
+    friend class Polygon;
 
 private:
     /*!
@@ -318,113 +375,6 @@ private:
     static void smooth_outward_step(const Point p1, const int64_t shortcut_length2, ListPolyIt& p0_it, ListPolyIt& p2_it, bool& forward_is_blocked, bool& backward_is_blocked, bool& forward_is_too_far, bool& backward_is_too_far);
 };
 
-
-class PolygonRef : public ConstPolygonRef
-{
-    PolygonRef()
-    : ConstPolygonRef()
-    {}
-public:
-    PolygonRef(ClipperLib::Path& polygon)
-    : ConstPolygonRef(polygon)
-    {}
-
-    PolygonRef& operator=(const PolygonRef& other)
-    {
-        path = other.path;
-        return *this;
-    }
-
-    Point& operator[] (unsigned int index)
-    {
-        POLY_ASSERT(index < size());
-        return (*path)[index];
-    }
-
-    ClipperLib::Path::iterator begin()
-    {
-        return path->begin();
-    }
-
-    ClipperLib::Path::iterator end()
-    {
-        return path->end();
-    }
-
-    ClipperLib::Path::reference back()
-    {
-        return path->back();
-    }
-
-    void* data()
-    {
-        return path->data();
-    }
-
-    void add(const Point p)
-    {
-        path->push_back(p);
-    }
-
-    PolygonRef& operator=(ConstPolygonRef& other) { path = other.path; return *this; }
-
-    ClipperLib::Path& operator*()
-    {
-        return *path;
-    }
-
-    template <typename... Args>
-    void emplace_back(Args&&... args)
-    {
-        path->emplace_back(args...);
-    }
-
-    void remove(unsigned int index)
-    {
-        POLY_ASSERT(index < size() && index <= std::numeric_limits<int>::max());
-        path->erase(path->begin() + index);
-    }
-
-    void clear()
-    {
-        path->clear();
-    }
-
-    void reverse()
-    {
-        ClipperLib::ReversePath(*path);
-    }
-
-    /*!
-     * Translate the whole polygon in some direction.
-     * 
-     * \param translation The direction in which to move the polygon
-     */
-    void translate(Point translation)
-    {
-        for (Point& p : *this)
-        {
-            p += translation;
-        }
-    }
-
-    /*! 
-     * Removes consecutive line segments with same orientation and changes this polygon.
-     * 
-     * Removes verts which are connected to line segments which are both too small.
-     * Removes verts which detour from a direct line from the previous and next vert by a too small amount.
-     * 
-     * \param smallest_line_segment_squared maximal squared length of removed line segments
-     * \param allowed_error_distance_squared The square of the distance of the middle point to the line segment of the consecutive and previous point for which the middle point is removed
-     */
-    void simplify(int smallest_line_segment_squared = 100, int allowed_error_distance_squared = 25);
-
-    void pop_back()
-    { 
-        path->pop_back();
-    }
-};
-
 class Polygon : public PolygonRef
 {
     ClipperLib::Path poly;
@@ -434,7 +384,7 @@ public:
     {
     }
 
-    Polygon(PolygonRef& other)
+    Polygon(const PolygonRef& other)
     : PolygonRef(poly)
     {
         poly = *other.path;
@@ -447,7 +397,6 @@ class Polygons
 {
     friend class Polygon;
     friend class PolygonRef;
-    friend class ConstPolygonRef;
 protected:
     ClipperLib::Paths paths;
 public:
@@ -461,12 +410,11 @@ public:
     PolygonRef operator[] (unsigned int index)
     {
         POLY_ASSERT(index < size() && index <= std::numeric_limits<int>::max());
-        return paths[index];
+        return PolygonRef(paths[index]);
     }
-    ConstPolygonRef operator[] (unsigned int index) const
+    const PolygonRef operator[] (unsigned int index) const
     {
-        POLY_ASSERT(index < size() && index <= std::numeric_limits<int>::max());
-        return paths[index];
+        return const_cast<Polygons*>(this)->operator[](index);
     }
     ClipperLib::Paths::iterator begin()
     {
@@ -509,11 +457,7 @@ public:
     {
         paths.clear();
     }
-    void add(ConstPolygonRef& poly)
-    {
-        paths.push_back(*poly.path);
-    }
-    void add(const ConstPolygonRef& poly)
+    void add(const PolygonRef& poly)
     {
         paths.push_back(*poly.path);
     }
@@ -549,10 +493,6 @@ public:
     {
         return PolygonRef(paths.back());
     }
-    ConstPolygonRef back() const
-    {
-        return ConstPolygonRef(paths.back());
-    }
 
     Polygons() {}
 
@@ -707,7 +647,7 @@ public:
      * \param remove_length The length of the largest segment removed
      * \return The smoothed polygon
      */
-    Polygons smooth(int remove_length) const;
+    Polygons smooth(int remove_length);
 
     /*!
      * Smooth out sharp inner corners, by taking a shortcut which bypasses the corner
@@ -718,7 +658,7 @@ public:
      */
     Polygons smooth_outward(float angle, int shortcut_length);
 
-    Polygons smooth2(int remove_length, int min_area) const; //!< removes points connected to small lines
+    Polygons smooth2(int remove_length, int min_area); //!< removes points connected to small lines
     
     /*!
      * removes points connected to similarly oriented lines
@@ -858,16 +798,16 @@ public:
      * Removes the same polygons from this set (and also empty polygons).
      * Polygons are considered the same if all points lie within [same_distance] of their counterparts.
      */
-    Polygons remove(const Polygons& to_be_removed, int same_distance = 0) const
+    Polygons remove(Polygons& to_be_removed, int same_distance = 0)
     {
         Polygons result;
         for (unsigned int poly_keep_idx = 0; poly_keep_idx < size(); poly_keep_idx++)
         {
-            ConstPolygonRef poly_keep = (*this)[poly_keep_idx];
+            PolygonRef poly_keep = (*this)[poly_keep_idx];
             bool should_be_removed = false;
             if (poly_keep.size() > 0) 
 //             for (int hole_poly_idx = 0; hole_poly_idx < to_be_removed.size(); hole_poly_idx++)
-            for (ConstPolygonRef poly_rem : to_be_removed)
+            for (PolygonRef poly_rem : to_be_removed)
             {
 //                 PolygonRef poly_rem = to_be_removed[hole_poly_idx];
                 if (poly_rem.size() != poly_keep.size() || poly_rem.size() == 0) continue;
@@ -934,6 +874,8 @@ public:
         }
         return length;
     }
+
+    int64_t polyLineLength() const;
     
     Point min() const
     {
@@ -983,16 +925,13 @@ public:
 class PolygonsPart : public Polygons
 {   
 public:
-    PolygonRef outerPolygon()
+    PolygonRef outerPolygon() 
     {
-        return this->paths[0];
-    }
-    ConstPolygonRef outerPolygon() const
-    {
-        return this->paths[0];
+        Polygons& thiss = *this;
+        return thiss[0];
     }
     
-    bool inside(Point p)
+    bool inside(Point p) const
     {
         if (size() < 1)
             return false;
@@ -1005,6 +944,8 @@ public:
         }
         return true;
     }
+
+    double area() const;
 };
 
 /*!
@@ -1022,7 +963,7 @@ public:
      * \param boundary_poly_idx Optional output parameter: The index of the boundary polygon of the part in \p polygons
      * \return The PolygonsPart containing the polygon with index \p poly_idx
      */
-    unsigned int getPartContaining(unsigned int poly_idx, unsigned int* boundary_poly_idx = nullptr) const;
+    unsigned int getPartContaining(unsigned int poly_idx, unsigned int* boundary_poly_idx = nullptr);
     /*!
      * Assemble the PolygonsPart of which the polygon with index \p poly_idx is part.
      * 
@@ -1030,7 +971,7 @@ public:
      * \param boundary_poly_idx Optional output parameter: The index of the boundary polygon of the part in \p polygons
      * \return The PolygonsPart containing the polygon with index \p poly_idx
      */
-    PolygonsPart assemblePartContaining(unsigned int poly_idx, unsigned int* boundary_poly_idx = nullptr) const;
+    PolygonsPart assemblePartContaining(unsigned int poly_idx, unsigned int* boundary_poly_idx = nullptr);
     /*!
      * Assemble the PolygonsPart of which the polygon with index \p poly_idx is part.
      * 

src/utils/polygonUtils.cpp

@@ -22,7 +22,7 @@ int64_t PolygonUtils::segmentLength(PolygonsPointIndex start, PolygonsPointIndex
     assert(start.poly_idx == end.poly_idx);
     int64_t segment_length = 0;
     Point prev_vert = start.p();
-    ConstPolygonRef poly = (*start.polygons)[start.poly_idx];
+    const PolygonRef poly = (*start.polygons)[start.poly_idx];
     for (unsigned int point_idx = 1; point_idx <= poly.size(); point_idx++)
     {
         unsigned int vert_idx = (start.point_idx + point_idx) % poly.size();
@@ -44,7 +44,7 @@ void PolygonUtils::spreadDots(PolygonsPointIndex start, PolygonsPointIndex end,
     assert(start.poly_idx == end.poly_idx);
     int64_t segment_length = segmentLength(start, end);
 
-    ConstPolygonRef poly = (*start.polygons)[start.poly_idx];
+    const PolygonRef poly = (*start.polygons)[start.poly_idx];
     unsigned int n_dots_in_between = n_dots;
     if (start == end)
     {
@@ -80,7 +80,7 @@ void PolygonUtils::spreadDots(PolygonsPointIndex start, PolygonsPointIndex end,
     assert(result.size() == n_dots && "we didn't generate as many wipe locations as we asked for.");
 }
 
-Point PolygonUtils::getVertexInwardNormal(ConstPolygonRef poly, unsigned int point_idx)
+Point PolygonUtils::getVertexInwardNormal(PolygonRef poly, unsigned int point_idx)
 {
     Point p1 = poly[point_idx];
 
@@ -110,7 +110,7 @@ Point PolygonUtils::getVertexInwardNormal(ConstPolygonRef poly, unsigned int poi
             break;
         }
     }
-    const Point& p2 = poly[p2_idx];
+    Point& p2 = poly[p2_idx];
 
     Point off0 = turn90CCW(normal(p1 - p0, MM2INT(10.0))); // 10.0 for some precision
     Point off1 = turn90CCW(normal(p2 - p1, MM2INT(10.0))); // 10.0 for some precision
@@ -119,7 +119,7 @@ Point PolygonUtils::getVertexInwardNormal(ConstPolygonRef poly, unsigned int poi
 }
 
 
-Point PolygonUtils::getBoundaryPointWithOffset(ConstPolygonRef poly, unsigned int point_idx, int64_t offset)
+Point PolygonUtils::getBoundaryPointWithOffset(PolygonRef poly, unsigned int point_idx, int64_t offset)
 {
     return poly[point_idx] + normal(getVertexInwardNormal(poly, point_idx), -offset);
 }
@@ -130,7 +130,7 @@ Point PolygonUtils::moveInsideDiagonally(ClosestPolygonPoint point_on_boundary,
     {
         return no_point;
     }
-    ConstPolygonRef poly = *point_on_boundary.poly;
+    PolygonRef poly = *point_on_boundary.poly;
     Point p0 = poly[point_on_boundary.point_idx];
     Point p1 = poly[(point_on_boundary.point_idx + 1) % poly.size()];
     if (vSize2(p0 - point_on_boundary.location) < vSize2(p1 - point_on_boundary.location))
@@ -163,7 +163,7 @@ ClosestPolygonPoint PolygonUtils::moveInside2(const Polygons& polygons, Point& f
     return _moveInside2(*closest_polygon_point, distance, from, max_dist2);
 }
 
-ClosestPolygonPoint PolygonUtils::moveInside2(const Polygons& loc_to_line_polygons, ConstPolygonRef polygon, Point& from, const int distance, const int64_t max_dist2, const LocToLineGrid* loc_to_line_grid, const std::function<int(Point)>& penalty_function)
+ClosestPolygonPoint PolygonUtils::moveInside2(const Polygons& loc_to_line_polygons, const PolygonRef polygon, Point& from, const int distance, const int64_t max_dist2, const LocToLineGrid* loc_to_line_grid, const std::function<int(Point)>& penalty_function)
 {
     std::optional<ClosestPolygonPoint> closest_polygon_point;
     if (loc_to_line_grid)
@@ -225,7 +225,7 @@ unsigned int PolygonUtils::moveInside(const Polygons& polygons, Point& from, int
     bool is_already_on_correct_side_of_boundary = false; // whether [from] is already on the right side of the boundary
     for (unsigned int poly_idx = 0; poly_idx < polygons.size(); poly_idx++)
     {
-        ConstPolygonRef poly = polygons[poly_idx];
+        const PolygonRef poly = polygons[poly_idx];
         if (poly.size() < 2)
             continue;
         Point p0 = poly[poly.size()-2];
@@ -344,11 +344,11 @@ Point PolygonUtils::moveInside(const ClosestPolygonPoint& cpp, const int distanc
     { // the point which is assumed to be on the boundary doesn't have to be moved
         return cpp.location;
     }
-    ConstPolygonRef poly = *cpp.poly;
+    const PolygonRef poly = *cpp.poly;
     unsigned int point_idx = cpp.point_idx;
     const Point& on_boundary = cpp.location;
 
-    const Point& p1 = poly[point_idx];
+    Point& p1 = poly[point_idx];
     unsigned int p2_idx;
     for (p2_idx = point_idx + 1; p2_idx != point_idx; p2_idx = p2_idx + 1)
     { // find the next point different from p1
@@ -361,7 +361,7 @@ Point PolygonUtils::moveInside(const ClosestPolygonPoint& cpp, const int distanc
             break;
         }
     }
-    const Point& p2 = poly[p2_idx];
+    Point& p2 = poly[p2_idx];
 
     if (on_boundary == p1)
     {
@@ -392,7 +392,7 @@ ClosestPolygonPoint PolygonUtils::ensureInsideOrOutside(const Polygons& polygons
     {
         return ClosestPolygonPoint(); // we couldn't move inside
     }
-    ConstPolygonRef closest_poly = *closest_polygon_point.poly;
+    PolygonRef closest_poly = *closest_polygon_point.poly;
     bool is_outside_boundary = closest_poly.orientation();
 
     {
@@ -481,8 +481,8 @@ void PolygonUtils::findSmallestConnection(ClosestPolygonPoint& poly1_result, Clo
     {
         return;
     }
-    ConstPolygonRef poly1 = *poly1_result.poly;
-    ConstPolygonRef poly2 = *poly2_result.poly;
+    PolygonRef poly1 = *poly1_result.poly;
+    PolygonRef poly2 = *poly2_result.poly;
     if (poly1.size() == 0 || poly2.size() == 0)
     {
         return;
@@ -515,8 +515,8 @@ void PolygonUtils::walkToNearestSmallestConnection(ClosestPolygonPoint& poly1_re
     {
         return;
     }
-    ConstPolygonRef poly1 = *poly1_result.poly;
-    ConstPolygonRef poly2 = *poly2_result.poly;
+    PolygonRef poly1 = *poly1_result.poly;
+    PolygonRef poly2 = *poly2_result.poly;
     if (poly1_result.point_idx < 0 || poly2_result.point_idx < 0)
     {
         return;
@@ -537,7 +537,7 @@ void PolygonUtils::walkToNearestSmallestConnection(ClosestPolygonPoint& poly1_re
     }
 }
 
-ClosestPolygonPoint PolygonUtils::findNearestClosest(Point from, ConstPolygonRef polygon, int start_idx)
+ClosestPolygonPoint PolygonUtils::findNearestClosest(Point from, PolygonRef polygon, int start_idx)
 {
     ClosestPolygonPoint forth = findNearestClosest(from, polygon, start_idx, 1);
     if (!forth.isValid())
@@ -556,7 +556,7 @@ ClosestPolygonPoint PolygonUtils::findNearestClosest(Point from, ConstPolygonRef
     }
 }
 
-ClosestPolygonPoint PolygonUtils::findNearestClosest(Point from, ConstPolygonRef polygon, int start_idx, int direction)
+ClosestPolygonPoint PolygonUtils::findNearestClosest(Point from, PolygonRef polygon, int start_idx, int direction)
 {
     if (polygon.size() == 0)
     {
@@ -572,8 +572,8 @@ ClosestPolygonPoint PolygonUtils::findNearestClosest(Point from, ConstPolygonRef
     {
         int p1_idx = (polygon.size() + direction*p + start_idx) % polygon.size();
         int p2_idx = (polygon.size() + direction*(p+1) + start_idx) % polygon.size();
-        const Point& p1 = polygon[p1_idx];
-        const Point& p2 = polygon[p2_idx];
+        Point& p1 = polygon[p1_idx];
+        Point& p2 = polygon[p2_idx];
 
         Point closest_here = LinearAlg2D::getClosestOnLineSegment(from, p1 ,p2);
         int64_t dist = vSize2(from - closest_here);
@@ -600,7 +600,7 @@ ClosestPolygonPoint PolygonUtils::findClosest(Point from, const Polygons& polygo
     {
         return none;
     }
-    ConstPolygonRef any_polygon = polygons[0];
+    PolygonRef any_polygon = polygons[0];
     unsigned int any_poly_idx;
     for (any_poly_idx = 0; any_poly_idx < polygons.size(); any_poly_idx++)
     { // find first point in all polygons
@@ -620,7 +620,7 @@ ClosestPolygonPoint PolygonUtils::findClosest(Point from, const Polygons& polygo
     
     for (unsigned int ply = 0; ply < polygons.size(); ply++)
     {
-        ConstPolygonRef poly = polygons[ply];
+        const PolygonRef poly = polygons[ply];
         if (poly.size() == 0) continue;
         ClosestPolygonPoint closest_here = findClosest(from, poly, penalty_function);
         if (!closest_here.isValid())
@@ -639,7 +639,7 @@ ClosestPolygonPoint PolygonUtils::findClosest(Point from, const Polygons& polygo
     return best;
 }
 
-ClosestPolygonPoint PolygonUtils::findClosest(Point from, ConstPolygonRef polygon, const std::function<int(Point)>& penalty_function)
+ClosestPolygonPoint PolygonUtils::findClosest(Point from, const PolygonRef polygon, const std::function<int(Point)>& penalty_function)
 {
     if (polygon.size() == 0)
     {
@@ -653,11 +653,11 @@ ClosestPolygonPoint PolygonUtils::findClosest(Point from, ConstPolygonRef polygo
 //
     for (unsigned int p = 0; p<polygon.size(); p++)
     {
-        const Point& p1 = polygon[p];
+        Point& p1 = polygon[p];
 
         unsigned int p2_idx = p+1;
         if (p2_idx >= polygon.size()) p2_idx = 0;
-        const Point& p2 = polygon[p2_idx];
+        Point& p2 = polygon[p2_idx];
 
         Point closest_here = LinearAlg2D::getClosestOnLineSegment(from, p1 ,p2);
         int64_t dist2_score = vSize2(from - closest_here) + penalty_function(closest_here);
@@ -678,7 +678,7 @@ PolygonsPointIndex PolygonUtils::findNearestVert(const Point from, const Polygon
     PolygonsPointIndex closest_vert;
     for (unsigned int poly_idx = 0; poly_idx < polys.size(); poly_idx++)
     {
-        ConstPolygonRef poly = polys[poly_idx];
+        const PolygonRef poly = polys[poly_idx];
         for (unsigned int point_idx = 0; point_idx < poly.size(); point_idx++)
         {
             int64_t dist2 = vSize2(poly[point_idx] - from);
@@ -692,7 +692,7 @@ PolygonsPointIndex PolygonUtils::findNearestVert(const Point from, const Polygon
     return closest_vert;
 }
 
-unsigned int PolygonUtils::findNearestVert(const Point from, ConstPolygonRef poly)
+unsigned int PolygonUtils::findNearestVert(const Point from, const PolygonRef poly)
 {
     int64_t best_dist2 = std::numeric_limits<int64_t>::max();
     unsigned int closest_vert_idx = -1;
@@ -721,7 +721,7 @@ LocToLineGrid* PolygonUtils::createLocToLineGrid(const Polygons& polygons, int s
 
     for (unsigned int poly_idx = 0; poly_idx < polygons.size(); poly_idx++)
     {
-        ConstPolygonRef poly = polygons[poly_idx];
+        const PolygonRef poly = polygons[poly_idx];
         for (unsigned int point_idx = 0; point_idx < poly.size(); point_idx++)
         {
             ret->insert(PolygonsPointIndex(&polygons, poly_idx, point_idx));
@@ -752,9 +752,9 @@ std::optional<ClosestPolygonPoint> PolygonUtils::findClose(
     PolygonsPointIndex best_point_poly_idx(nullptr, NO_INDEX, NO_INDEX);
     for (PolygonsPointIndex& point_poly_index : near_lines)
     {
-        ConstPolygonRef poly = polygons[point_poly_index.poly_idx];
-        const Point& p1 = poly[point_poly_index.point_idx];
-        const Point& p2 = poly[(point_poly_index.point_idx + 1) % poly.size()];
+        const PolygonRef poly = polygons[point_poly_index.poly_idx];
+        Point& p1 = poly[point_poly_index.point_idx];
+        Point& p2 = poly[(point_poly_index.point_idx + 1) % poly.size()];
 
         Point closest_here = LinearAlg2D::getClosestOnLineSegment(from, p1 ,p2);
         int64_t dist2_score = vSize2(from - closest_here) + penalty_function(closest_here);
@@ -778,7 +778,7 @@ std::optional<ClosestPolygonPoint> PolygonUtils::findClose(
 
 
 std::vector<std::pair<ClosestPolygonPoint, ClosestPolygonPoint>> PolygonUtils::findClose(
-    ConstPolygonRef from, const Polygons& destination,
+    const PolygonRef from, const Polygons& destination,
     const LocToLineGrid& destination_loc_to_line,
     const std::function<int(Point)>& penalty_function)
 {
@@ -817,7 +817,7 @@ std::vector<std::pair<ClosestPolygonPoint, ClosestPolygonPoint>> PolygonUtils::f
 
 
 
-bool PolygonUtils::getNextPointWithDistance(Point from, int64_t dist, ConstPolygonRef poly, int start_idx, int poly_start_idx, GivenDistPoint& result)
+bool PolygonUtils::getNextPointWithDistance(Point from, int64_t dist, const PolygonRef poly, int start_idx, int poly_start_idx, GivenDistPoint& result)
 {
     
     Point prev_poly_point = poly[(start_idx + poly_start_idx) % poly.size()];
@@ -825,7 +825,7 @@ bool PolygonUtils::getNextPointWithDistance(Point from, int64_t dist, ConstPolyg
     for (unsigned int prev_idx = start_idx; prev_idx < poly.size(); prev_idx++) 
     {
         int next_idx = (prev_idx + 1 + poly_start_idx) % poly.size(); // last checked segment is between last point in poly and poly[0]...
-        const Point& next_poly_point = poly[next_idx];
+        Point& next_poly_point = poly[next_idx];
         if ( !shorterThen(next_poly_point - from, dist) )
         {
             /*
@@ -932,7 +932,7 @@ bool PolygonUtils::polygonCollidesWithLineSegment(const Point from, const Point
     return ret;
 }
 
-bool PolygonUtils::polygonCollidesWithLineSegment(ConstPolygonRef poly, const Point& transformed_startPoint, const Point& transformed_endPoint, PointMatrix transformation_matrix)
+bool PolygonUtils::polygonCollidesWithLineSegment(const PolygonRef poly, Point& transformed_startPoint, Point& transformed_endPoint, PointMatrix transformation_matrix)
 {
     Point p0 = transformation_matrix.apply(poly.back());
     for(Point p1_ : poly)
@@ -947,7 +947,7 @@ bool PolygonUtils::polygonCollidesWithLineSegment(ConstPolygonRef poly, const Po
     return false;
 }
 
-bool PolygonUtils::polygonCollidesWithLineSegment(ConstPolygonRef poly, const Point& startPoint, const Point& endPoint)
+bool PolygonUtils::polygonCollidesWithLineSegment(const PolygonRef poly, Point& startPoint, Point& endPoint)
 {
     Point diff = endPoint - startPoint;
 
@@ -958,9 +958,9 @@ bool PolygonUtils::polygonCollidesWithLineSegment(ConstPolygonRef poly, const Po
     return PolygonUtils::polygonCollidesWithLineSegment(poly, transformed_startPoint, transformed_endPoint, transformation_matrix);
 }
 
-bool PolygonUtils::polygonCollidesWithLineSegment(const Polygons& polys, const Point& transformed_startPoint, const Point& transformed_endPoint, PointMatrix transformation_matrix)
+bool PolygonUtils::polygonCollidesWithLineSegment(const Polygons& polys, Point& transformed_startPoint, Point& transformed_endPoint, PointMatrix transformation_matrix)
 {
-    for (ConstPolygonRef poly : polys)
+    for (const PolygonRef poly : const_cast<Polygons&>(polys))
     {
         if (poly.size() == 0) { continue; }
         if (PolygonUtils::polygonCollidesWithLineSegment(poly, transformed_startPoint, transformed_endPoint, transformation_matrix))
@@ -973,7 +973,7 @@ bool PolygonUtils::polygonCollidesWithLineSegment(const Polygons& polys, const P
 }
 
 
-bool PolygonUtils::polygonCollidesWithLineSegment(const Polygons& polys, const Point& startPoint, const Point& endPoint)
+bool PolygonUtils::polygonCollidesWithLineSegment(const Polygons& polys, Point& startPoint, Point& endPoint)
 {
     Point diff = endPoint - startPoint;
 

src/utils/polygonUtils.h

@@ -20,12 +20,12 @@ namespace cura
 struct ClosestPolygonPoint
 {
     Point location; //!< Result location
-    std::optional<ConstPolygonRef> poly; //!< Polygon in which the result was found (or none if no result was found)
+    std::optional<PolygonRef> poly; //!< Polygon in which the result was found (or none if no result was found)
     unsigned int poly_idx; //!< The index of the polygon in some Polygons where ClosestPolygonPoint::poly can be found
     unsigned int point_idx; //!< Index to the first point in the polygon of the line segment on which the result was found
-    ClosestPolygonPoint(Point p, int pos, ConstPolygonRef poly) :  location(p), poly(true, poly), poly_idx(NO_INDEX), point_idx(pos) {};
-    ClosestPolygonPoint(Point p, int pos, ConstPolygonRef poly, int poly_idx) :  location(p), poly(true, poly), poly_idx(poly_idx), point_idx(pos) {};
-    ClosestPolygonPoint(ConstPolygonRef poly) : poly(true, poly), poly_idx(NO_INDEX), point_idx(NO_INDEX) {};
+    ClosestPolygonPoint(Point p, int pos, PolygonRef poly) :  location(p), poly(true, poly), poly_idx(NO_INDEX), point_idx(pos) {};
+    ClosestPolygonPoint(Point p, int pos, PolygonRef poly, int poly_idx) :  location(p), poly(true, poly), poly_idx(poly_idx), point_idx(pos) {};
+    ClosestPolygonPoint(PolygonRef poly) : poly(true, poly), poly_idx(NO_INDEX), point_idx(NO_INDEX) {};
     ClosestPolygonPoint() : poly_idx(NO_INDEX), point_idx(NO_INDEX) {};
     Point p() const
     { // conformity with other classes
@@ -53,7 +53,7 @@ struct PolygonsPointIndexSegmentLocator
 {
     std::pair<Point, Point> operator()(const PolygonsPointIndex& val) const
     {
-        ConstPolygonRef poly = (*val.polygons)[val.poly_idx];
+        PolygonRef poly = (*val.polygons)[val.poly_idx];
         Point start = poly[val.point_idx];
         unsigned int next_point_idx = (val.point_idx + 1) % poly.size();
         Point end = poly[next_point_idx];
@@ -104,7 +104,7 @@ public:
      * \param poly The polygon.
      * \param point_idx The index of the point in the polygon.
      */
-    static Point getVertexInwardNormal(ConstPolygonRef poly, unsigned int point_idx);
+    static Point getVertexInwardNormal(PolygonRef poly, unsigned int point_idx);
 
     /*!
     * Get a point from the \p poly with a given \p offset.
@@ -114,7 +114,7 @@ public:
     * \param offset The distance the point has to be moved outward from the polygon.
     * \return A point at the given distance inward from the point on the boundary polygon.
     */
-    static Point getBoundaryPointWithOffset(ConstPolygonRef poly, unsigned int point_idx, int64_t offset);
+    static Point getBoundaryPointWithOffset(PolygonRef poly, unsigned int point_idx, int64_t offset);
 
     /*!
      * Move a point away from the boundary by looking at the boundary normal of the nearest vert.
@@ -178,7 +178,7 @@ public:
      * \param penalty_function A function returning a penalty term on the squared distance score of a candidate point.
      * \return The point on the polygon closest to \p from
      */
-    static ClosestPolygonPoint moveInside2(const Polygons& loc_to_line_polygons, ConstPolygonRef polygon, Point& from, const int distance = 0, const int64_t max_dist2 = std::numeric_limits<int64_t>::max(), const LocToLineGrid* loc_to_line_grid = nullptr, const std::function<int(Point)>& penalty_function = no_penalty_function);
+    static ClosestPolygonPoint moveInside2(const Polygons& loc_to_line_polygons, const PolygonRef polygon, Point& from, const int distance = 0, const int64_t max_dist2 = std::numeric_limits<int64_t>::max(), const LocToLineGrid* loc_to_line_grid = nullptr, const std::function<int(Point)>& penalty_function = no_penalty_function);
 
     /*!
      * The opposite of moveInside.
@@ -298,7 +298,7 @@ public:
     * \param start_idx The index of the point in the polygon from which to start looking.
     * \return The nearest point from \p start_idx going along the \p polygon (in both directions) with a locally minimal distance to \p from.
     */
-    static ClosestPolygonPoint findNearestClosest(Point from, ConstPolygonRef polygon, int start_idx);
+    static ClosestPolygonPoint findNearestClosest(Point from, const PolygonRef polygon, int start_idx);
 
     /*!
     * Find the nearest closest point on a polygon from a given index walking in one direction along the polygon.
@@ -309,7 +309,7 @@ public:
     * \param direction The direction to walk: 1 for walking along the \p polygon, -1 for walking in opposite direction
     * \return The nearest point from \p start_idx going along the \p polygon with a locally minimal distance to \p from.
     */
-    static ClosestPolygonPoint findNearestClosest(const Point from, ConstPolygonRef polygon, int start_idx, int direction);
+    static ClosestPolygonPoint findNearestClosest(const Point from, const PolygonRef polygon, int start_idx, int direction);
 
     /*!
      * Find the point closest to \p from in all polygons in \p polygons.
@@ -327,7 +327,7 @@ public:
      * 
      * \param penalty_function A function returning a penalty term on the squared distance score of a candidate point.
      */
-    static ClosestPolygonPoint findClosest(Point from, ConstPolygonRef polygon, const std::function<int(Point)>& penalty_function = no_penalty_function);
+    static ClosestPolygonPoint findClosest(Point from, const PolygonRef polygon, const std::function<int(Point)>& penalty_function = no_penalty_function);
 
     /*!
      * Find the nearest vertex to \p from in \p polys
@@ -343,7 +343,7 @@ public:
      * \param poly The polygon in which to search
      * \return The index to the nearest vertex on the polygon
      */
-    static unsigned int findNearestVert(const Point from, ConstPolygonRef poly);
+    static unsigned int findNearestVert(const Point from, const PolygonRef poly);
 
     /*!
      * Create a SparsePointGridInclusive mapping from locations to line segments occurring in the \p polygons
@@ -382,7 +382,7 @@ public:
      * \param penalty_function A function returning a penalty term on the squared distance score of a candidate point.
      * \return A collection of near crossing from the \p from polygon to the \p destination polygon. Each element in the sollection is a pair with as first a cpp in the \p from polygon and as second a cpp in the \p destination polygon.
      */
-    static std::vector<std::pair<ClosestPolygonPoint, ClosestPolygonPoint>> findClose(ConstPolygonRef from, const Polygons& destination, const LocToLineGrid& destination_loc_to_line, const std::function<int(Point)>& penalty_function = no_penalty_function);
+    static std::vector<std::pair<ClosestPolygonPoint, ClosestPolygonPoint>> findClose(const PolygonRef from, const Polygons& destination, const LocToLineGrid& destination_loc_to_line, const std::function<int(Point)>& penalty_function = no_penalty_function);
 
     /*!
      * Checks whether a given line segment collides with polygons as given in a loc_to_line grid.
@@ -409,7 +409,7 @@ public:
     * \param start_idx the index of the prev poly point on the poly.
     * \param poly_start_idx The index of the point in the polygon which is to be handled as the start of the polygon. No point further than this point will be the result.
     */
-    static bool getNextPointWithDistance(Point from, int64_t dist, ConstPolygonRef poly, int start_idx, int poly_start_idx, GivenDistPoint& result);
+    static bool getNextPointWithDistance(Point from, int64_t dist, const PolygonRef poly, int start_idx, int poly_start_idx, GivenDistPoint& result);
 
 
 
@@ -433,7 +433,7 @@ public:
      * \return whether the line segment collides with the boundary of the
      * polygon(s)
      */
-    static bool polygonCollidesWithLineSegment(ConstPolygonRef poly, const Point& transformed_startPoint, const Point& transformed_endPoint, PointMatrix transformation_matrix);
+    static bool polygonCollidesWithLineSegment(const PolygonRef poly, Point& transformed_startPoint, Point& transformed_endPoint, PointMatrix transformation_matrix);
 
     /*!
      * Checks whether a given line segment collides with a given polygon(s).
@@ -449,7 +449,7 @@ public:
      * \return whether the line segment collides with the boundary of the
      * polygon(s)
      */
-    static bool polygonCollidesWithLineSegment(ConstPolygonRef poly, const Point& startPoint, const Point& endPoint);
+    static bool polygonCollidesWithLineSegment(const PolygonRef poly, Point& startPoint, Point& endPoint);
 
     /*!
      * Checks whether a given line segment collides with a given polygon(s).
@@ -471,7 +471,7 @@ public:
      * \return whether the line segment collides with the boundary of the
      * polygon(s)
      */
-    static bool polygonCollidesWithLineSegment(const Polygons& polys, const Point& transformed_startPoint, const Point& transformed_endPoint, PointMatrix transformation_matrix);
+    static bool polygonCollidesWithLineSegment(const Polygons& polys, Point& transformed_startPoint, Point& transformed_endPoint, PointMatrix transformation_matrix);
 
     /*!
      * Checks whether a given line segment collides with a given polygon(s).
@@ -487,7 +487,7 @@ public:
      * \return whether the line segment collides with the boundary of the
      * polygon(s)
      */
-    static bool polygonCollidesWithLineSegment(const Polygons& polys, const Point& startPoint, const Point& endPoint);
+    static bool polygonCollidesWithLineSegment(const Polygons& polys, Point& startPoint, Point& endPoint);
 
 private:
     /*!

src/wallOverlap.cpp

@@ -18,7 +18,7 @@ WallOverlapComputation::WallOverlapComputation(Polygons& polygons, int line_widt
 }
 
 
-float WallOverlapComputation::getFlow(const Point& from, const Point& to)
+float WallOverlapComputation::getFlow(Point& from, Point& to)
 {
     using Point2LinkIt = PolygonProximityLinker::Point2Link::iterator;
 

src/wallOverlap.h

@@ -60,7 +60,7 @@ public:
      * \param to The ending of the line segment
      * \return a value between zero and one representing the reduced flow of the line segment
      */
-    float getFlow(const Point& from, const Point& to);
+    float getFlow(Point& from, Point& to);
 
     /*!
      * Computes the neccesary priliminaries in order to efficiently compute the flow when generatign gcode paths.