#211 % max speed reduction

waiting for a good name

resources/ui_layout/filament.ui

@@ -30,7 +30,8 @@ group:Short layer time - began to increase base fan speed
 	setting:label$Max fan speed:max_fan_speed
 group:Very short layer time - began to decrease extrusion rate
 	setting:label$Layer time goal:slowdown_below_layer_time
-	setting:min_print_speed
+	setting:width$4:max_speed_reduction
+	setting:width$4:min_print_speed
 group:Behavior
 	cooling_description
 

src/libslic3r/Config.hpp

@@ -867,6 +867,7 @@ public:
     ConfigOption*           clone() const override { return new ConfigOptionPercentsTempl(*this); }
     ConfigOptionPercentsTempl&   operator=(const ConfigOption *opt) { this->set(opt); return *this; }
     bool                    operator==(const ConfigOptionPercentsTempl &rhs) const { return this->values == rhs.values; }
+    double                  get_abs_value(size_t i, double ratio_over) const { return is_nil(i) ? 0 : ratio_over * get_at(i) / 100; }
 
     std::string serialize() const override
     {

src/libslic3r/GCode/CoolingBuffer.cpp

@@ -193,6 +193,11 @@ struct PerExtruderAdjustments
             if (line.feedrate > min_feedrate) {
                 line.time *= std::max(1.f, line.feedrate / min_feedrate);
                 line.feedrate = min_feedrate;
+                //test to never go over max_time
+                if (line.time > line.time_max) {
+                    line.time = line.time_max;
+                    line.feedrate = line.length / line.time;
+                }
                 line.slowdown = true;
             }
         }
@@ -206,6 +211,8 @@ struct PerExtruderAdjustments
     float                       slowdown_below_layer_time = 0.f;
     // Minimum print speed allowed for this extruder.
     float                       min_print_speed     = 0.f;
+    // Max speed reduction allowed for this extruder.
+    float                       max_speed_reduction = 1;
 
     // Parsed lines.
     std::vector<CoolingLine>    lines;
@@ -307,6 +314,7 @@ std::vector<PerExtruderAdjustments> CoolingBuffer::parse_layer_gcode(const std::
         adj.cooling_slow_down_enabled = config.cooling.get_at(extruder_id);
         adj.slowdown_below_layer_time = float(config.slowdown_below_layer_time.get_at(extruder_id));
         adj.min_print_speed           = float(config.min_print_speed.get_at(extruder_id));
+        adj.max_speed_reduction       = float(config.max_speed_reduction.get_at(extruder_id) / 100);
         map_extruder_to_per_extruder_adjustment[extruder_id] = i;
     }
 
@@ -394,8 +402,11 @@ std::vector<PerExtruderAdjustments> CoolingBuffer::parse_layer_gcode(const std::
                 if (line.length > 0)
                     line.time = line.length / line.feedrate;
                 line.time_max = line.time;
-                if ((line.type & CoolingLine::TYPE_ADJUSTABLE) || active_speed_modifier != size_t(-1))
+                if ((line.type & CoolingLine::TYPE_ADJUSTABLE) || active_speed_modifier != size_t(-1)) {
                     line.time_max = (adjustment->min_print_speed == 0.f) ? FLT_MAX : std::max(line.time, line.length / adjustment->min_print_speed);
+                    if(adjustment->max_speed_reduction > 0)
+                        line.time_max = std::min(line.time_max, line.time / (1- adjustment->max_speed_reduction));
+                }
                 if (active_speed_modifier < adjustment->lines.size() && (line.type & CoolingLine::TYPE_G1)) {
                     // Inside the ";_EXTRUDE_SET_SPEED" blocks, there must not be a G1 Fxx entry.
                     assert((line.type & CoolingLine::TYPE_HAS_F) == 0);
@@ -534,8 +545,10 @@ static inline void extruder_range_slow_down_non_proportional(
     }
     assert(feedrate > 0.f);
     // Sort by min_print_speed, maximum speed first.
+    //multiplied by max_speed_reductionto be able to sort them when only this one change.
     std::sort(by_min_print_speed.begin(), by_min_print_speed.end(), 
-        [](const PerExtruderAdjustments *p1, const PerExtruderAdjustments *p2){ return p1->min_print_speed > p2->min_print_speed; });
+        [](const PerExtruderAdjustments *p1, const PerExtruderAdjustments *p2){ 
+        return (1 - p1->max_speed_reduction) * p1->min_print_speed > (1 - p2->max_speed_reduction) * p2->min_print_speed; });
     // Slow down, fast moves first.
     for (;;) {
         // For each extruder, find the span of lines with a feedrate close to feedrate.
@@ -552,6 +565,7 @@ static inline void extruder_range_slow_down_non_proportional(
         // Slow down, limited by max(feedrate_next, min_print_speed).
         for (auto adj = by_min_print_speed.begin(); adj != by_min_print_speed.end();) {
             // Slow down at most by time_stretch.
+            //note: the max_speed reduction is used via the max_time, nothing else to do as it's a proportional limit.
             if ((*adj)->min_print_speed == 0.f) {
                 // All the adjustable speeds are now lowered to the same speed,
                 // and the minimum speed is set to zero.
@@ -580,7 +594,7 @@ static inline void extruder_range_slow_down_non_proportional(
             }
             // Skip the other extruders with nearly the same min_print_speed, as they have been processed already.
             auto next = adj;
-            for (++ next; next != by_min_print_speed.end() && (*next)->min_print_speed > (*adj)->min_print_speed - EPSILON; ++ next);
+            for (++ next; next != by_min_print_speed.end() && (*next)->min_print_speed > (*adj)->min_print_speed - EPSILON && (*next)->max_speed_reduction < (*adj)->max_speed_reduction + EPSILON; ++ next);
             adj = next;
         }
         if (feedrate_next == 0.f)

src/libslic3r/PrintConfig.cpp

@@ -1950,6 +1950,16 @@ void PrintConfigDef::init_fff_params()
     def->mode = comExpert;
     def->set_default_value(new ConfigOptionFloat(80));
 
+    def = this->add("max_speed_reduction", coPercents);
+    def->label = L("Max speed reduction");
+    def->category = OptionCategory::speed;
+    def->tooltip = L("Amount of speed you can reduce per extrusion speed.");
+    def->sidetext = L("%");
+    def->min = 0;
+    def->max = 100;
+    def->mode = comExpert;
+    def->set_default_value(new ConfigOptionPercents{ 90 });
+
     def = this->add("max_volumetric_speed", coFloat);
     def->label = L("Max volumetric speed");
     def->category = OptionCategory::extruders;

src/libslic3r/PrintConfig.hpp

@@ -1060,6 +1060,7 @@ public:
     ConfigOptionInts                max_fan_speed;
     ConfigOptionFloats              max_layer_height;
     ConfigOptionFloat               max_print_height;
+    ConfigOptionPercents            max_speed_reduction;
     ConfigOptionFloats              milling_diameter;
     ConfigOptionStrings             milling_toolchange_end_gcode;
     ConfigOptionStrings             milling_toolchange_start_gcode;
@@ -1148,6 +1149,7 @@ protected:
         OPT_PTR(max_fan_speed);
         OPT_PTR(max_layer_height);
         OPT_PTR(max_print_height);
+        OPT_PTR(max_speed_reduction);
         OPT_PTR(milling_diameter);
         OPT_PTR(milling_toolchange_end_gcode);
         OPT_PTR(milling_toolchange_start_gcode);

src/slic3r/GUI/Preset.cpp

@@ -457,7 +457,8 @@ const std::vector<std::string>& Preset::print_options()
         , "bottom_fill_pattern"
         , "solid_fill_pattern",
         "infill_every_layers", "infill_only_where_needed", "solid_infill_every_layers", "fill_angle", "bridge_angle", 
-        "solid_infill_below_area", "only_retract_when_crossing_perimeters", "infill_first", "max_print_speed", 
+        "solid_infill_below_area", "only_retract_when_crossing_perimeters", "infill_first", 
+        "max_print_speed",
         "max_volumetric_speed", 
 #ifdef HAS_PRESSURE_EQUALIZER
         "max_volumetric_extrusion_rate_slope_positive", "max_volumetric_extrusion_rate_slope_negative", 
@@ -566,7 +567,10 @@ const std::vector<std::string>& Preset::filament_options()
         "max_fan_speed", "bridge_fan_speed"
         , "top_fan_speed"
         , "disable_fan_first_layers"
-        , "fan_below_layer_time", "slowdown_below_layer_time", "min_print_speed",
+        , "fan_below_layer_time", 
+        "slowdown_below_layer_time",
+        "max_speed_reduction",
+        "min_print_speed",
         "start_filament_gcode", "end_filament_gcode",
         "external_perimeter_fan_speed",
         // Retract overrides

src/slic3r/GUI/PresetHints.cpp

@@ -26,6 +26,7 @@ std::string PresetHints::cooling_description(const Preset &preset)
     int     disable_fan_first_layers = preset.config.opt_int("disable_fan_first_layers", 0);
     int     slowdown_below_layer_time = preset.config.opt_int("slowdown_below_layer_time", 0);
     int     min_print_speed = int(preset.config.opt_float("min_print_speed", 0) + 0.5);
+    int     max_speed_reduc = int(preset.config.opt_float("max_speed_reduction", 0));
     int     fan_below_layer_time = preset.config.opt_int("fan_below_layer_time", 0);
 
     //if (preset.config.opt_bool("cooling", 0)) {
@@ -97,9 +98,14 @@ std::string PresetHints::cooling_description(const Preset &preset)
         }
             
         out += " " + (boost::format(_utf8(L("print speed will be reduced "
-            "so that no less than %1%s are spent on that layer "
+            "so that no less than %1%s are spent on that layer"))) % slowdown_below_layer_time).str();
-            "(however, speed will never be reduced below %2%mm/s).")))
+        if(min_print_speed > 0)
-            % slowdown_below_layer_time % min_print_speed).str();
+            if(max_speed_reduc > 0)
+                out += " " + (boost::format(_utf8(L("(however, speed will never be reduced below %1%mm/s or up to %2%%% reduction)")))
+                    % min_print_speed % max_speed_reduc).str();
+            else
+                out += " " + (boost::format(_utf8(L("(however, speed will never be reduced below %1%mm/s)")))
+                    % min_print_speed).str();
     }
 
     return out;