Number of slow layers #796

src/libslic3r/GCode.cpp

@@ -4000,6 +4000,21 @@ std::string GCode::_extrude(const ExtrusionPath &path, std::string description,
         if (path.role() != erBottomSurface)
             speed = m_config.get_abs_value("initial_layer_speed");
     }
+    else if(m_config.slow_down_layers > 1){
+        const auto _layer = layer_id() + 1;
+        if (_layer > 0 && _layer < m_config.slow_down_layers) {
+            const auto first_layer_speed =
+                is_perimeter(path.role())
+                    ? m_config.get_abs_value("initial_layer_speed")
+                    : m_config.get_abs_value("initial_layer_infill_speed");
+            if (first_layer_speed < speed) {
+                speed = std::min(
+                    speed,
+                    Slic3r::lerp(first_layer_speed, speed,
+                                 (double)_layer / m_config.slow_down_layers));
+            }
+        }
+    }
     //BBS: remove this config
     //else if (this->object_layer_over_raft())
     //    speed = m_config.get_abs_value("first_layer_speed_over_raft", speed);

src/libslic3r/GCode.hpp

@@ -511,7 +511,12 @@ private:
     void _print_first_layer_extruder_temperatures(GCodeOutputStream &file, Print &print, const std::string &gcode, unsigned int first_printing_extruder_id, bool wait);
     // On the first printing layer. This flag triggers first layer speeds.
     //BBS
-    bool                                on_first_layer() const { return m_layer != nullptr && m_layer->id() == 0 && abs(m_layer->bottom_z()) < EPSILON; }
+    bool    on_first_layer() const { return m_layer != nullptr && m_layer->id() == 0 && abs(m_layer->bottom_z()) < EPSILON; }
+    int layer_id() const {
+        if (m_layer == nullptr)
+            return -1;
+        return m_layer->id();
+    }
     // To control print speed of 1st object layer over raft interface.
     bool                                object_layer_over_raft() const { return m_object_layer_over_raft; }
 

src/libslic3r/Preset.cpp

@@ -756,7 +756,7 @@ static std::vector<std::string> s_Preset_print_options {
      "bridge_density", "precise_outer_wall", "overhang_speed_classic", "bridge_acceleration",
      "sparse_infill_acceleration", "internal_solid_infill_acceleration", "tree_support_adaptive_layer_height", "tree_support_auto_brim", 
      "tree_support_brim_width", "gcode_comments", "gcode_label_objects",
-     "initial_layer_travel_speed", "exclude_object"
+     "initial_layer_travel_speed", "exclude_object", "slow_down_layers"
 
 };
 

src/libslic3r/Print.cpp

@@ -229,7 +229,8 @@ bool Print::invalidate_state_by_config_options(const ConfigOptionResolver & /* n
             || opt_key == "travel_speed"
             || opt_key == "travel_speed_z"
             || opt_key == "initial_layer_speed"
-            || opt_key == "initial_layer_travel_speed") {
+            || opt_key == "initial_layer_travel_speed"
+            || opt_key == "slow_down_layers") {
             //|| opt_key == "z_offset") {
             steps.emplace_back(psWipeTower);
             steps.emplace_back(psSkirtBrim);

src/libslic3r/PrintConfig.cpp

@@ -1631,6 +1631,14 @@ void PrintConfigDef::init_fff_params()
     def->mode = comAdvanced;
     def->set_default_value(new ConfigOptionFloatOrPercent(100, true));
 
+    def = this->add("slow_down_layers", coInt);
+    def->label = L("Number of slow layers");
+    def->tooltip = L("The first few layers are printed slower than normal. "
+                     "The speed is gradually increased in a linear fashion over the specified number of layers.");
+    def->category = L("Speed");
+    def->min = 0;
+    def->mode = comAdvanced;
+    def->set_default_value(new ConfigOptionInt(0));
 
     def = this->add("nozzle_temperature_initial_layer", coInts);
     def->label = L("Initial layer");

src/libslic3r/PrintConfig.hpp

@@ -1010,6 +1010,8 @@ PRINT_CONFIG_CLASS_DERIVED_DEFINE(
     ((ConfigOptionBool,                gcode_label_objects))
     ((ConfigOptionBool,                exclude_object))
     ((ConfigOptionBool,                gcode_comments))
+    ((ConfigOptionInt,                 slow_down_layers))
+
 
 )
 

src/slic3r/GUI/Tab.cpp

@@ -1922,6 +1922,7 @@ void TabPrint::build()
         optgroup->append_single_option_line("initial_layer_speed");
         optgroup->append_single_option_line("initial_layer_infill_speed");
         optgroup->append_single_option_line("initial_layer_travel_speed");
+        optgroup->append_single_option_line("slow_down_layers");
         optgroup = page->new_optgroup(L("Other layers speed"), L"param_speed", 15);
         optgroup->append_single_option_line("outer_wall_speed");
         optgroup->append_single_option_line("inner_wall_speed");