Implemented dynamic fan control. Cooling buffer does not yet relfect that

src/libslic3r/GCode.cpp

@@ -2868,19 +2868,37 @@ std::string GCode::_extrude(const ExtrusionPath &path, const std::string_view de
         );
     }
 
-    bool                        variable_speed = false;
+    bool                        variable_speed_or_fan_speed = false;
     std::vector<ProcessedPoint> new_points{};
-    if (this->m_config.enable_dynamic_overhang_speeds && !this->on_first_layer() && path.role().is_perimeter()) {
+    if ((this->m_config.enable_dynamic_overhang_speeds || this->config().enable_dynamic_fan_speeds.get_at(m_writer.extruder()->id())) &&
-        std::vector<std::pair<int, ConfigOptionFloatOrPercent>> overhangs_with_speeds{
+        !this->on_first_layer() && path.role().is_perimeter()) {
-            {0, m_config.overhang_speed_0},  {20, m_config.overhang_speed_1}, {40, m_config.overhang_speed_2},
+        std::vector<std::pair<int, ConfigOptionFloatOrPercent>> overhangs_with_speeds = {{100, ConfigOptionFloatOrPercent{speed, false}}};
-            {60, m_config.overhang_speed_3}, {80, m_config.overhang_speed_4},
+        if (this->m_config.enable_dynamic_overhang_speeds) {
-        };
+            std::vector<std::pair<int, ConfigOptionFloatOrPercent>> overhangs_with_speeds = {{0, m_config.overhang_speed_0},
+                                                                                             {25, m_config.overhang_speed_1},
+                                                                                             {50, m_config.overhang_speed_2},
+                                                                                             {75, m_config.overhang_speed_3},
+                                                                                             {100,
+                                                                                              ConfigOptionFloatOrPercent{speed, false}}};
+        }
+
+        std::vector<std::pair<int, ConfigOptionInts>> overhang_w_fan_speeds = {{100, ConfigOptionInts{0}}};
+        if (this->m_config.enable_dynamic_fan_speeds.get_at(m_writer.extruder()->id())) {
+            std::vector<std::pair<int, ConfigOptionInts>> overhang_w_fan_speeds = {{0, m_config.overhang_fan_speed_0},
+                                                                                   {25, m_config.overhang_fan_speed_1},
+                                                                                   {50, m_config.overhang_fan_speed_2},
+                                                                                   {75, m_config.overhang_fan_speed_3},
+                                                                                   {100, ConfigOptionInts{0}}};
+        }
+
         double external_perim_reference_speed = std::min(m_config.get_abs_value("external_perimeter_speed"),
                                                          std::min(EXTRUDER_CONFIG(filament_max_volumetric_speed) / path.mm3_per_mm,
                                                                   m_config.max_volumetric_speed.value / path.mm3_per_mm));
-        new_points = m_extrusion_quality_estimator.estimate_extrusion_quality(path, overhangs_with_speeds, external_perim_reference_speed,
+        new_points = m_extrusion_quality_estimator.estimate_extrusion_quality(path, overhangs_with_speeds, overhang_w_fan_speeds,
+                                                                              m_writer.extruder()->id(), external_perim_reference_speed,
                                                                               speed);
-        variable_speed = std::any_of(new_points.begin(), new_points.end(), [speed](const ProcessedPoint &p) { return p.speed != speed; });
+        variable_speed_or_fan_speed = std::any_of(new_points.begin(), new_points.end(),
+                                                  [speed](const ProcessedPoint &p) { return p.speed != speed || p.fan_speed != 0; });
     }
 
     double F = speed * 60;  // convert mm/sec to mm/min
@@ -2944,7 +2962,7 @@ std::string GCode::_extrude(const ExtrusionPath &path, const std::string_view de
             cooling_marker_setspeed_comments += ";_EXTERNAL_PERIMETER";
     }
 
-    if (!variable_speed) {
+    if (!variable_speed_or_fan_speed) {
         // F is mm per minute.
         gcode += m_writer.set_speed(F, "", cooling_marker_setspeed_comments);
         double path_length = 0.;
@@ -2970,7 +2988,9 @@ std::string GCode::_extrude(const ExtrusionPath &path, const std::string_view de
             marked_comment += description_bridge;
         }
         double last_set_speed     = new_points[0].speed * 60.0;
+        double last_set_fan_speed = new_points[0].fan_speed;
         gcode += m_writer.set_speed(last_set_speed, "", cooling_marker_setspeed_comments);
+        gcode += m_writer.set_fan(last_set_fan_speed);
         Vec2d prev = this->point_to_gcode_quantized(new_points[0].p);
         for (size_t i = 1; i < new_points.size(); i++) {
             const ProcessedPoint &processed_point = new_points[i];
@@ -2983,6 +3003,10 @@ std::string GCode::_extrude(const ExtrusionPath &path, const std::string_view de
                 gcode += m_writer.set_speed(new_speed, "", cooling_marker_setspeed_comments);
                 last_set_speed = new_speed;
             }
+            if (last_set_fan_speed != processed_point.fan_speed) {
+                gcode += m_writer.set_fan(processed_point.fan_speed);
+                last_set_fan_speed = processed_point.fan_speed;
+            }
         }
     }
 

src/libslic3r/GCode/ExtrusionProcessor.hpp

@@ -238,6 +238,7 @@ struct ProcessedPoint
 {
     Point p;
     float speed = 1.0f;
+    int fan_speed = 0;
 };
 
 class ExtrusionQualityEstimator
@@ -259,31 +260,25 @@ public:
 
     std::vector<ProcessedPoint> estimate_extrusion_quality(const ExtrusionPath                                          &path,
                                                            const std::vector<std::pair<int, ConfigOptionFloatOrPercent>> overhangs_w_speeds,
+                                                           const std::vector<std::pair<int, ConfigOptionInts>> overhangs_w_fan_speeds,
+                                                           size_t                                              extruder_id,
                                                            float                                               ext_perimeter_speed,
                                                            float                                               original_speed)
     {
         float                  speed_base = ext_perimeter_speed > 0 ? ext_perimeter_speed : original_speed;
-        std::vector<std::pair<float, float>> speed_sections;
+        std::map<float, float> speed_sections;
         for (size_t i = 0; i < overhangs_w_speeds.size(); i++) {
             float distance           = path.width * (1.0 - (overhangs_w_speeds[i].first / 100.0));
             float speed              = overhangs_w_speeds[i].second.percent ? (speed_base * overhangs_w_speeds[i].second.value / 100.0) :
                                                                               overhangs_w_speeds[i].second.value;
-            speed_sections.push_back({distance, speed});
+            speed_sections[distance] = speed;
         }
-        std::sort(speed_sections.begin(), speed_sections.end(), [](const std::pair<float, float> &a, const std::pair<float, float> &b) {
-            if (a.first == b.first) {
-                return a.second > b.second;
-            }
-            return a.first < b.first;
-        });
 
-        std::pair<float, float> last_section{INFINITY, 0};
+        std::map<float, float> fan_speed_sections;
-        for (auto &section : speed_sections) {
+        for (size_t i = 0; i < overhangs_w_fan_speeds.size(); i++) {
-            if (section.first == last_section.first) {
+            float distance           = path.width * (1.0 - (overhangs_w_fan_speeds[i].first / 100.0));
-                section.second = last_section.second;
+            float fan_speed            = overhangs_w_fan_speeds[i].second.get_at(extruder_id);
-            } else {
+            fan_speed_sections[distance] = fan_speed;
-                last_section = section;
-            }
         }
 
         std::vector<ExtendedPoint> extended_points =
@@ -295,28 +290,26 @@ public:
             const ExtendedPoint &curr = extended_points[i];
             const ExtendedPoint &next = extended_points[i + 1 < extended_points.size() ? i + 1 : i];
 
-            auto calculate_speed = [&speed_sections, &original_speed](float distance) {
+            auto interpolate_speed = [](const std::map<float, float> &values, float distance) {
-                float final_speed;
+                auto upper_dist = values.lower_bound(distance);
-                if (distance <= speed_sections.front().first) {
+                if (upper_dist == values.end()) {
-                    final_speed = original_speed;
+                    return values.rend()->second;
-                } else if (distance >= speed_sections.back().first) {
-                    final_speed = speed_sections.back().second;
-                } else {
-                    size_t section_idx = 0;
-                    while (distance > speed_sections[section_idx + 1].first) {
-                        section_idx++;
                 }
-                    float t = (distance - speed_sections[section_idx].first) /
+                if (upper_dist == values.begin()) {
-                              (speed_sections[section_idx + 1].first - speed_sections[section_idx].first);
+                    return upper_dist->second;
-                    t           = std::clamp(t, 0.0f, 1.0f);
-                    final_speed = (1.0f - t) * speed_sections[section_idx].second + t * speed_sections[section_idx + 1].second;
                 }
-                return final_speed;
+
+                auto  lower_dist = --upper_dist;
+                float t          = (distance - lower_dist->first) / (upper_dist->first - lower_dist->first);
+                return (1.0f - t) * lower_dist->second + t * upper_dist->second;
             };
 
-            float extrusion_speed = std::min(calculate_speed(curr.distance), calculate_speed(next.distance));
+            float extrusion_speed = std::min(interpolate_speed(speed_sections, curr.distance),
+                                             interpolate_speed(speed_sections, next.distance));
+            float fan_speed       = std::min(interpolate_speed(fan_speed_sections, curr.distance),
+                                             interpolate_speed(fan_speed_sections, next.distance));
 
-            processed_points.push_back({scaled(curr.position), extrusion_speed});
+            processed_points.push_back({scaled(curr.position), extrusion_speed, int(fan_speed)});
         }
         return processed_points;
     }

src/libslic3r/Preset.cpp

@@ -440,7 +440,7 @@ static std::vector<std::string> s_Preset_print_options {
     "fuzzy_skin", "fuzzy_skin_thickness", "fuzzy_skin_point_dist",
     "max_volumetric_extrusion_rate_slope_positive", "max_volumetric_extrusion_rate_slope_negative",
     "perimeter_speed", "small_perimeter_speed", "external_perimeter_speed", "infill_speed", "solid_infill_speed",
-    "enable_dynamic_overhang_speeds", "overhang_speed_0", "overhang_speed_1", "overhang_speed_2", "overhang_speed_3", "overhang_speed_4",
+    "enable_dynamic_overhang_speeds", "overhang_speed_0", "overhang_speed_1", "overhang_speed_2", "overhang_speed_3",
     "top_solid_infill_speed", "support_material_speed", "support_material_xy_spacing", "support_material_interface_speed",
     "bridge_speed", "gap_fill_speed", "gap_fill_enabled", "travel_speed", "travel_speed_z", "first_layer_speed", "first_layer_speed_over_raft", "perimeter_acceleration", "infill_acceleration",
     "external_perimeter_acceleration", "top_solid_infill_acceleration", "solid_infill_acceleration",
@@ -473,7 +473,8 @@ static std::vector<std::string> s_Preset_filament_options {
     "filament_cooling_initial_speed", "filament_cooling_final_speed", "filament_ramming_parameters", "filament_minimal_purge_on_wipe_tower",
     "temperature", "idle_temperature", "first_layer_temperature", "bed_temperature", "first_layer_bed_temperature", "fan_always_on", "cooling", "min_fan_speed",
     "max_fan_speed", "bridge_fan_speed", "disable_fan_first_layers", "full_fan_speed_layer", "fan_below_layer_time", "slowdown_below_layer_time", "min_print_speed",
-    "start_filament_gcode", "end_filament_gcode",
+    "start_filament_gcode", "end_filament_gcode", "enable_dynamic_fan_speeds",
+    "overhang_fan_speed_0", "overhang_fan_speed_1", "overhang_fan_speed_2", "overhang_fan_speed_3",
     // Retract overrides
     "filament_retract_length", "filament_retract_lift", "filament_retract_lift_above", "filament_retract_lift_below", "filament_retract_speed", "filament_deretract_speed", "filament_retract_restart_extra", "filament_retract_before_travel",
     "filament_retract_layer_change", "filament_wipe", "filament_retract_before_wipe",

src/libslic3r/Print.cpp

@@ -66,6 +66,11 @@ bool Print::invalidate_state_by_config_options(const ConfigOptionResolver & /* n
         "between_objects_gcode",
         "bridge_acceleration",
         "bridge_fan_speed",
+        "enable_dynamic_fan_speeds",
+        "overhang_fan_speed_0",
+        "overhang_fan_speed_1",
+        "overhang_fan_speed_2",
+        "overhang_fan_speed_3",
         "colorprint_heights",
         "cooling",
         "default_acceleration",

src/libslic3r/PrintConfig.cpp

@@ -535,7 +535,7 @@ void PrintConfigDef::init_fff_params()
     def->label      = L("Enable dynamic overhang speeds");
     def->category   = L("Speed");
     def->tooltip    = L("This setting enables dynamic speed control on overhangs.");
-    def->mode       = comAdvanced;
+    def->mode       = comExpert;
     def->set_default_value(new ConfigOptionBool(false));
 
     auto overhang_speed_setting_description = L("Overhang size is expressed as a percentage of overlap of the extrusion with the previous layer: "
@@ -549,44 +549,82 @@ void PrintConfigDef::init_fff_params()
     def->tooltip    = overhang_speed_setting_description;
     def->sidetext   = L("mm/s or %");
     def->min        = 0;
-    def->mode       = comAdvanced;
+    def->mode       = comExpert;
     def->set_default_value(new ConfigOptionFloatOrPercent(15, false));
 
     def             = this->add("overhang_speed_1", coFloatOrPercent);
-    def->label      = L("speed for 20\% overlap");
+    def->label      = L("speed for 25\% overlap");
     def->category   = L("Speed");
     def->tooltip    = overhang_speed_setting_description;
     def->sidetext   = L("mm/s or %");
     def->min        = 0;
-    def->mode       = comAdvanced;
+    def->mode       = comExpert;
-    def->set_default_value(new ConfigOptionFloatOrPercent(20, false));
+    def->set_default_value(new ConfigOptionFloatOrPercent(15, false));
 
     def             = this->add("overhang_speed_2", coFloatOrPercent);
-    def->label      = L("speed for 40\% overlap");
+    def->label      = L("speed for 50\% overlap");
     def->category   = L("Speed");
     def->tooltip    = overhang_speed_setting_description;
     def->sidetext   = L("mm/s or %");
     def->min        = 0;
-    def->mode       = comAdvanced;
+    def->mode       = comExpert;
-    def->set_default_value(new ConfigOptionFloatOrPercent(25, false));
+    def->set_default_value(new ConfigOptionFloatOrPercent(20, false));
 
     def             = this->add("overhang_speed_3", coFloatOrPercent);
-    def->label      = L("speed for 60\% overlap");
+    def->label      = L("speed for 75\% overlap");
     def->category   = L("Speed");
     def->tooltip    = overhang_speed_setting_description;
     def->sidetext   = L("mm/s or %");
     def->min        = 0;
-    def->mode       = comAdvanced;
+    def->mode       = comExpert;
     def->set_default_value(new ConfigOptionFloatOrPercent(25, false));
 
-    def             = this->add("overhang_speed_4", coFloatOrPercent);
+    def          = this->add("enable_dynamic_fan_speeds", coBools);
-    def->label      = L("speed for 80\% overlap");
+    def->label   = L("Enable dynamic fan speeds");
-    def->category   = L("Speed");
+    def->tooltip = L("This setting enables dynamic fan speed control on overhangs.");
-    def->tooltip    = overhang_speed_setting_description;
+    def->mode    = comExpert;
-    def->sidetext   = L("mm/s or %");
+    def->set_default_value(new ConfigOptionBools{false});
+
+    auto fan_speed_setting_description = L(
+        "Overhang size is expressed as a percentage of overlap of the extrusion with the previous layer: "
+        "100% would be full overlap (no overhang), while 0% represents full overhang (floating extrusion, bridge). "
+        "Fan speeds for overhang sizes in between are calculated via linear interpolation. ");
+
+    def           = this->add("overhang_fan_speed_0", coInts);
+    def->label    = L("speed for 0\% overlap (bridge)");
+    def->tooltip  = fan_speed_setting_description;
+    def->sidetext = L("%");
     def->min      = 0;
-    def->mode       = comAdvanced;
+    def->max      = 100;
-    def->set_default_value(new ConfigOptionFloatOrPercent(25, false));
+    def->mode     = comExpert;
+    def->set_default_value(new ConfigOptionInts{100});
+
+    def           = this->add("overhang_fan_speed_1", coInts);
+    def->label    = L("speed for 25\% overlap");
+    def->tooltip  = fan_speed_setting_description;
+    def->sidetext = L("%");
+    def->min      = 0;
+    def->max      = 100;
+    def->mode     = comExpert;
+    def->set_default_value(new ConfigOptionInts{75});
+
+    def           = this->add("overhang_fan_speed_2", coInts);
+    def->label    = L("speed for 50\% overlap");
+    def->tooltip  = fan_speed_setting_description;
+    def->sidetext = L("%");
+    def->min      = 0;
+    def->max      = 100;
+    def->mode     = comExpert;
+    def->set_default_value(new ConfigOptionInts{50});
+
+    def           = this->add("overhang_fan_speed_3", coInts);
+    def->label    = L("speed for 75\% overlap");
+    def->tooltip  = fan_speed_setting_description;
+    def->sidetext = L("%");
+    def->min      = 0;
+    def->max      = 100;
+    def->mode     = comExpert;
+    def->set_default_value(new ConfigOptionInts{25});
 
     def = this->add("brim_width", coFloat);
     def->label = L("Brim width");

src/libslic3r/PrintConfig.hpp

@@ -577,7 +577,6 @@ PRINT_CONFIG_CLASS_DEFINE(
     ((ConfigOptionFloatOrPercent,       overhang_speed_1))
     ((ConfigOptionFloatOrPercent,       overhang_speed_2))
     ((ConfigOptionFloatOrPercent,       overhang_speed_3))
-    ((ConfigOptionFloatOrPercent,       overhang_speed_4))
     ((ConfigOptionBool,                 external_perimeters_first))
     ((ConfigOptionBool,                 extra_perimeters))
     ((ConfigOptionBool,                 extra_perimeters_on_overhangs))
@@ -750,6 +749,11 @@ PRINT_CONFIG_CLASS_DERIVED_DEFINE(
     ((ConfigOptionInts,               bed_temperature))
     ((ConfigOptionFloat,              bridge_acceleration))
     ((ConfigOptionInts,               bridge_fan_speed))
+    ((ConfigOptionBools,              enable_dynamic_fan_speeds))
+    ((ConfigOptionInts,               overhang_fan_speed_0))
+    ((ConfigOptionInts,               overhang_fan_speed_1))
+    ((ConfigOptionInts,               overhang_fan_speed_2))
+    ((ConfigOptionInts,               overhang_fan_speed_3))
     ((ConfigOptionBool,               complete_objects))
     ((ConfigOptionFloats,             colorprint_heights))
     ((ConfigOptionBools,              cooling))

src/libslic3r/PrintObject.cpp

@@ -769,7 +769,6 @@ bool PrintObject::invalidate_state_by_config_options(
             || opt_key == "overhang_speed_1"
             || opt_key == "overhang_speed_2"
             || opt_key == "overhang_speed_3"
-            || opt_key == "overhang_speed_4"
             || opt_key == "external_perimeter_speed"
             || opt_key == "infill_speed"
             || opt_key == "perimeter_speed"

src/slic3r/GUI/Tab.cpp

@@ -1554,7 +1554,6 @@ void TabPrint::build()
         optgroup->append_single_option_line("overhang_speed_1");
         optgroup->append_single_option_line("overhang_speed_2");
         optgroup->append_single_option_line("overhang_speed_3");
-        optgroup->append_single_option_line("overhang_speed_4");
 
         optgroup = page->new_optgroup(L("Speed for non-print moves"));
         optgroup->append_single_option_line("travel_speed");
@@ -1988,6 +1987,13 @@ void TabFilament::build()
         optgroup->append_single_option_line("disable_fan_first_layers", category_path + "fan-settings");
         optgroup->append_single_option_line("full_fan_speed_layer", category_path + "fan-settings");
 
+        optgroup = page->new_optgroup(L("Dynamic fan speeds"), 25);
+        optgroup->append_single_option_line("enable_dynamic_fan_speeds", category_path + "dynamic-fan-speeds");
+        optgroup->append_single_option_line("overhang_fan_speed_0", category_path + "dynamic-fan-speeds");
+        optgroup->append_single_option_line("overhang_fan_speed_1", category_path + "dynamic-fan-speeds");
+        optgroup->append_single_option_line("overhang_fan_speed_2", category_path + "dynamic-fan-speeds");
+        optgroup->append_single_option_line("overhang_fan_speed_3", category_path + "dynamic-fan-speeds");
+
         optgroup = page->new_optgroup(L("Cooling thresholds"), 25);
         optgroup->append_single_option_line("fan_below_layer_time", category_path + "cooling-thresholds");
         optgroup->append_single_option_line("slowdown_below_layer_time", category_path + "cooling-thresholds");
@@ -2140,6 +2146,11 @@ void TabFilament::toggle_options()
 
         for (auto el : { "min_fan_speed", "disable_fan_first_layers", "full_fan_speed_layer" })
             toggle_option(el, fan_always_on);
+
+        bool dynamic_fan_speeds = m_config->opt_bool("enable_dynamic_fan_speeds", 0);
+        for (int i = 0; i < 4; i++) {
+        toggle_option("overhang_fan_speed_"+std::to_string(i),dynamic_fan_speeds);
+        }
     }
 
     if (m_active_page->title() == "Filament Overrides")