Separate extrusions ordering and extrusions exporting into two for loops

src/libslic3r/GCode.cpp

@@ -2462,39 +2462,44 @@ LayerResult GCodeGenerator::process_layer(
         }
     }
 
-    // Extrude the skirt, brim, support, perimeters, infill ordered by the extruders.
-    for (unsigned int extruder_id : layer_tools.extruders)
-    {
-        gcode += (layer_tools.has_wipe_tower && m_wipe_tower) ?
-            m_wipe_tower->tool_change(*this, extruder_id, extruder_id == layer_tools.extruders.back()) :
-            this->set_extruder(extruder_id, print_z);
-
-        // let analyzer tag generator aware of a role type change
-        if (layer_tools.has_wipe_tower && m_wipe_tower)
-            m_last_processor_extrusion_role = GCodeExtrusionRole::WipeTower;
-
-        if (has_custom_gcode_to_emit && extruder_id_for_custom_gcode == int(extruder_id)) {
-            assert(m_writer.extruder()->id() == extruder_id_for_custom_gcode);
-            assert(m_pending_pre_extrusion_gcode.empty());
-            // Now we have picked the right extruder, so we can emit the custom g-code.
-            gcode += ProcessLayer::emit_custom_gcode_per_print_z(*this, *layer_tools.custom_gcode, m_writer.extruder()->id(), first_extruder_id, print.config());
-        }
+    using GCode::ExtrusionOrder::NormalExtrusions;
+    struct ExtruderExtrusions {
+        unsigned extruder_id;
+        std::vector<std::pair<std::size_t, const ExtrusionEntity *>> skirt;
+        ExtrusionEntitiesPtr brim;
+        std::vector<std::vector<SliceExtrusions>> overriden_extrusions;
+        std::vector<NormalExtrusions> normal_extrusions;
+    };
 
+    unsigned current_extruder_id{this->m_writer.extruder()->id()};
+    unsigned toolchange_number{0};
     std::optional<Point> previous_position{this->last_position};
 
-        std::vector<std::pair<std::size_t, const ExtrusionEntity *>> skirt;
+    std::vector<ExtruderExtrusions> extrusions;
+    for (const unsigned int extruder_id : layer_tools.extruders)
+    {
+        if (layer_tools.has_wipe_tower && m_wipe_tower) {
+            if (is_toolchange_required(first_layer, layer_tools.extruders.back(), extruder_id, current_extruder_id)) {
+                const WipeTower::ToolChangeResult tool_change{m_wipe_tower->get_toolchange(toolchange_number++)};
+                previous_position = this->gcode_to_point(m_wipe_tower->transform_wt_pt(tool_change.end_pos).cast<double>());
+                current_extruder_id = tool_change.new_tool;
+            }
+        }
+
+        ExtruderExtrusions extruder_extrusions{extruder_id};
+
         if (auto loops_it = skirt_loops_per_extruder.find(extruder_id); loops_it != skirt_loops_per_extruder.end()) {
             const std::pair<size_t, size_t> loops = loops_it->second;
             for (std::size_t i = loops.first; i < loops.second; ++i) {
-                skirt.emplace_back(i, print.skirt().entities[i]);
+                extruder_extrusions.skirt.emplace_back(i, print.skirt().entities[i]);
             }
         }
 
         using GCode::ExtrusionOrder::get_last_position;
-        ExtrusionEntitiesPtr brim;
         if (!m_brim_done) {
-            brim = print.brim().entities;
-            previous_position = get_last_position(brim);
+            extruder_extrusions.brim = print.brim().entities;
+            previous_position = get_last_position(extruder_extrusions.brim);
+            m_brim_done = true;
         }
 
 
@@ -2519,22 +2524,40 @@ LayerResult GCodeGenerator::process_layer(
 
         using GCode::ExtrusionOrder::get_overriden_extrusions;
         bool is_anything_overridden = layer_tools.wiping_extrusions().is_anything_overridden();
-        std::vector<std::vector<SliceExtrusions>> overriden_extrusions;
         if (is_anything_overridden) {
-            overriden_extrusions = get_overriden_extrusions(
+            extruder_extrusions.overriden_extrusions = get_overriden_extrusions(
                 print, layers, layer_tools, instances_to_print, extruder_id, place_seam,
                 previous_position
             );
         }
 
         using GCode::ExtrusionOrder::get_normal_extrusions;
-        using GCode::ExtrusionOrder::NormalExtrusions;
-        const std::vector<NormalExtrusions> normal_extrusions{get_normal_extrusions(
+        extruder_extrusions.normal_extrusions = get_normal_extrusions(
             print, layers, layer_tools, instances_to_print, extruder_id, place_seam,
             previous_position
-        )};
+        );
+        extrusions.push_back(std::move(extruder_extrusions));
+    }
 
-        if (!skirt.empty()) {
+    // Extrude the skirt, brim, support, perimeters, infill ordered by the extruders.
+    for (const ExtruderExtrusions &extruder_extrusions : extrusions)
+    {
+        gcode += (layer_tools.has_wipe_tower && m_wipe_tower) ?
+            m_wipe_tower->tool_change(*this, extruder_extrusions.extruder_id, extruder_extrusions.extruder_id == layer_tools.extruders.back()) :
+            this->set_extruder(extruder_extrusions.extruder_id, print_z);
+
+        // let analyzer tag generator aware of a role type change
+        if (layer_tools.has_wipe_tower && m_wipe_tower)
+            m_last_processor_extrusion_role = GCodeExtrusionRole::WipeTower;
+
+        if (has_custom_gcode_to_emit && extruder_id_for_custom_gcode == int(extruder_extrusions.extruder_id)) {
+            assert(m_writer.extruder()->id() == extruder_id_for_custom_gcode);
+            assert(m_pending_pre_extrusion_gcode.empty());
+            // Now we have picked the right extruder, so we can emit the custom g-code.
+            gcode += ProcessLayer::emit_custom_gcode_per_print_z(*this, *layer_tools.custom_gcode, m_writer.extruder()->id(), first_extruder_id, print.config());
+        }
+
+        if (!extruder_extrusions.skirt.empty()) {
             if (!this->m_config.complete_objects.value) {
                 gcode += this->m_label_objects.maybe_stop_instance();
             }
@@ -2544,7 +2567,7 @@ LayerResult GCodeGenerator::process_layer(
             m_avoid_crossing_perimeters.use_external_mp();
             Flow layer_skirt_flow = print.skirt_flow().with_height(float(m_skirt_done.back() - (m_skirt_done.size() == 1 ? 0. : m_skirt_done[m_skirt_done.size() - 2])));
             double mm3_per_mm = layer_skirt_flow.mm3_per_mm();
-            for (const auto&[_, loop_entity] : skirt) {
+            for (const auto&[_, loop_entity] : extruder_extrusions.skirt) {
                 // Adjust flow according to this layer's layer height.
                 //FIXME using the support_material_speed of the 1st object printed.
                 gcode += this->extrude_skirt(dynamic_cast<const ExtrusionLoop&>(*loop_entity),
@@ -2554,13 +2577,13 @@ LayerResult GCodeGenerator::process_layer(
             }
             m_avoid_crossing_perimeters.use_external_mp(false);
             // Allow a straight travel move to the first object point if this is the first layer (but don't in next layers).
-            if (first_layer && skirt.front().first == 0)
+            if (first_layer && extruder_extrusions.skirt.front().first == 0)
                 m_avoid_crossing_perimeters.disable_once();
         }
 
 
         // Extrude brim with the extruder of the 1st region.
-        if (!brim.empty()) {
+        if (!extruder_extrusions.brim.empty()) {
 
             if (!this->m_config.complete_objects.value) {
                 gcode += this->m_label_objects.maybe_stop_instance();
@@ -2569,17 +2592,16 @@ LayerResult GCodeGenerator::process_layer(
 
             this->set_origin(0., 0.);
             m_avoid_crossing_perimeters.use_external_mp();
-            for (const ExtrusionEntity *ee : brim) {
+            for (const ExtrusionEntity *ee : extruder_extrusions.brim) {
                 gcode += this->extrude_entity({ *ee, false }, smooth_path_caches.global(), "brim"sv, m_config.support_material_speed.value);
             }
-            m_brim_done = true;
             m_avoid_crossing_perimeters.use_external_mp(false);
             // Allow a straight travel move to the first object point.
             m_avoid_crossing_perimeters.disable_once();
         }
         this->m_label_objects.update(first_instance);
 
-        if (!overriden_extrusions.empty()) {
+        if (!extruder_extrusions.overriden_extrusions.empty()) {
             // Extrude wipes.
             size_t gcode_size_old = gcode.size();
             for (std::size_t i{0}; i < instances_to_print.size(); ++i) {
@@ -2587,7 +2609,7 @@ LayerResult GCodeGenerator::process_layer(
 
                 this->process_layer_single_object(
                     gcode, instance, layers[instance.object_layer_to_print_id],
-                    smooth_path_caches.layer_local(), {}, overriden_extrusions[i]
+                    smooth_path_caches.layer_local(), {}, extruder_extrusions.overriden_extrusions[i]
                 );
             }
             if (gcode_size_old < gcode.size()) {
@@ -2601,8 +2623,8 @@ LayerResult GCodeGenerator::process_layer(
 
             this->process_layer_single_object(
                 gcode, instance, layers[instance.object_layer_to_print_id],
-                smooth_path_caches.layer_local(), normal_extrusions[i].support_extrusions,
-                normal_extrusions[i].slices_extrusions
+                smooth_path_caches.layer_local(), extruder_extrusions.normal_extrusions[i].support_extrusions,
+                extruder_extrusions.normal_extrusions[i].slices_extrusions
             );
         }
     }

src/libslic3r/GCode/WipeTowerIntegration.cpp

@@ -34,15 +34,6 @@ std::string WipeTowerIntegration::append_tcr(GCodeGenerator &gcodegen, const Wip
 
     std::string gcode;
 
-    // Toolchangeresult.gcode assumes the wipe tower corner is at the origin (except for priming lines)
-    // We want to rotate and shift all extrusions (gcode postprocessing) and starting and ending position
-    float alpha = m_wipe_tower_rotation / 180.f * float(M_PI);
-
-    auto transform_wt_pt = [&alpha, this](const Vec2f& pt) -> Vec2f {
-        Vec2f out = Eigen::Rotation2Df(alpha) * pt;
-        out += m_wipe_tower_pos;
-        return out;
-    };
 
     Vec2f start_pos = tcr.start_pos;
     Vec2f end_pos = tcr.end_pos;
@@ -52,7 +43,7 @@ std::string WipeTowerIntegration::append_tcr(GCodeGenerator &gcodegen, const Wip
     }
 
     Vec2f wipe_tower_offset = tcr.priming ? Vec2f::Zero() : m_wipe_tower_pos;
-    float wipe_tower_rotation = tcr.priming ? 0.f : alpha;
+    float wipe_tower_rotation = tcr.priming ? 0.f : this->get_alpha();
 
     std::string tcr_rotated_gcode = post_process_wipe_tower_moves(tcr, wipe_tower_offset, wipe_tower_rotation);
 
@@ -145,7 +136,7 @@ std::string WipeTowerIntegration::append_tcr(GCodeGenerator &gcodegen, const Wip
         Geometry::ArcWelder::Path path;
         path.reserve(tcr.wipe_path.size());
         std::transform(tcr.wipe_path.begin(), tcr.wipe_path.end(), std::back_inserter(path),
-            [&gcodegen, &transform_wt_pt](const Vec2f &wipe_pt) { 
+            [&gcodegen, this](const Vec2f &wipe_pt) {
                 return Geometry::ArcWelder::Segment{ wipe_tower_point_to_object_point(gcodegen, transform_wt_pt(wipe_pt)) };
             });
         // Pass to the wipe cache.

src/libslic3r/GCode/WipeTowerIntegration.hpp

@@ -39,8 +39,23 @@ public:
     std::string tool_change(GCodeGenerator &gcodegen, int extruder_id, bool finish_layer);
     std::string finalize(GCodeGenerator &gcodegen);
     std::vector<float> used_filament_length() const;
+    WipeTower::ToolChangeResult get_toolchange(std::size_t index) {
+        return m_tool_changes.at(m_layer_idx).at(index);
+    }
+
+    Vec2f transform_wt_pt(const Vec2f& pt) const {
+        Vec2f out = Eigen::Rotation2Df(this->get_alpha()) * pt;
+        out += m_wipe_tower_pos;
+        return out;
+    };
 
 private:
+    // Toolchangeresult.gcode assumes the wipe tower corner is at the origin (except for priming lines)
+    // We want to rotate and shift all extrusions (gcode postprocessing) and starting and ending position
+    float get_alpha() const {
+        return m_wipe_tower_rotation / 180.f * float(M_PI);
+    }
+
     WipeTowerIntegration& operator=(const WipeTowerIntegration&);
     std::string append_tcr(GCodeGenerator &gcodegen, const WipeTower::ToolChangeResult &tcr, int new_extruder_id, double z = -1.) const;
 

src/libslic3r/Print.cpp

@@ -1484,6 +1484,21 @@ const WipeTowerData& Print::wipe_tower_data(size_t extruders_cnt) const
     return m_wipe_tower_data;
 }
 
+bool is_toolchange_required(
+    const bool first_layer,
+    const unsigned last_extruder_id,
+    const unsigned extruder_id,
+    const unsigned current_extruder_id
+) {
+    if (first_layer && extruder_id == last_extruder_id) {
+        return true;
+    }
+    if (extruder_id != current_extruder_id) {
+        return true;
+    }
+    return false;
+}
+
 void Print::_make_wipe_tower()
 {
     m_wipe_tower_data.clear();
@@ -1552,10 +1567,11 @@ void Print::_make_wipe_tower()
         unsigned int current_extruder_id = m_wipe_tower_data.tool_ordering.all_extruders().back();
         for (auto &layer_tools : m_wipe_tower_data.tool_ordering.layer_tools()) { // for all layers
             if (!layer_tools.has_wipe_tower) continue;
-            bool first_layer = &layer_tools == &m_wipe_tower_data.tool_ordering.front();
             wipe_tower.plan_toolchange((float)layer_tools.print_z, (float)layer_tools.wipe_tower_layer_height, current_extruder_id, current_extruder_id, false);
             for (const auto extruder_id : layer_tools.extruders) {
-                if ((first_layer && extruder_id == m_wipe_tower_data.tool_ordering.all_extruders().back()) || extruder_id != current_extruder_id) {
+                const bool first_layer{&layer_tools == &m_wipe_tower_data.tool_ordering.front()};
+                const unsigned last_extruder_id{m_wipe_tower_data.tool_ordering.all_extruders().back()};
+                if (is_toolchange_required(first_layer, last_extruder_id, extruder_id, current_extruder_id)) {
                     float volume_to_wipe = wipe_volumes[current_extruder_id][extruder_id];             // total volume to wipe after this toolchange
                     // Not all of that can be used for infill purging:
                     volume_to_wipe -= (float)m_config.filament_minimal_purge_on_wipe_tower.get_at(extruder_id);

src/libslic3r/Print.hpp

@@ -493,6 +493,13 @@ private:
 	WipeTowerData &operator=(const WipeTowerData & /* rhs */) = delete;
 };
 
+bool is_toolchange_required(
+    const bool first_layer,
+    const unsigned last_extruder_id,
+    const unsigned extruder_id,
+    const unsigned current_extruder_id
+);
+
 struct PrintStatistics
 {
     PrintStatistics() { clear(); }