Added min_layer_height, max_layer_height per nozzle settings

for controlling the support layer height & variable layer height.
Added an experimental "rear" seam option.

lib/Slic3r/GUI/Tab.pm

@@ -1402,7 +1402,7 @@ sub _extruders_count_changed {
     $self->_on_value_change('extruders_count', $extruders_count);
 }
 
-sub _extruder_options { qw(nozzle_diameter extruder_offset retract_length retract_lift retract_lift_above retract_lift_below retract_speed retract_restart_extra retract_before_travel wipe
+sub _extruder_options { qw(nozzle_diameter min_layer_height max_layer_height extruder_offset retract_length retract_lift retract_lift_above retract_lift_below retract_speed retract_restart_extra retract_before_travel wipe
     retract_layer_change retract_length_toolchange retract_restart_extra_toolchange) }
 
 sub _build_extruder_pages {
@@ -1431,6 +1431,11 @@ sub _build_extruder_pages {
             my $optgroup = $page->new_optgroup('Size');
             $optgroup->append_single_option_line('nozzle_diameter', $extruder_idx);
         }
+        {
+            my $optgroup = $page->new_optgroup('Limits');
+            $optgroup->append_single_option_line($_, $extruder_idx)
+                for qw(min_layer_height max_layer_height);
+        }
         {
             my $optgroup = $page->new_optgroup('Position (for multi-extruder printers)');
             $optgroup->append_single_option_line('extruder_offset', $extruder_idx);

xs/src/libslic3r/GCode.cpp

@@ -565,31 +565,42 @@ GCode::extrude(ExtrusionLoop loop, std::string description, double speed)
     bool was_clockwise = loop.make_counter_clockwise();
     
     SeamPosition seam_position = this->config.seam_position;
-    if (loop.role == elrSkirt) seam_position = spNearest;
+    if (loop.role == elrSkirt) 
+        seam_position = spNearest;
     
     // find the point of the loop that is closest to the current extruder position
     // or randomize if requested
     Point last_pos = this->last_pos();
     if (this->config.spiral_vase) {
         loop.split_at(last_pos, false);
-    } else if (seam_position == spNearest || seam_position == spAligned) {
+    } else if (seam_position == spNearest || seam_position == spAligned || seam_position == spRear) {
         Polygon        polygon    = loop.polygon();
         const coordf_t nozzle_dmr = EXTRUDER_CONFIG(nozzle_diameter);
         const coord_t  nozzle_r   = scale_(0.5*nozzle_dmr);
 
         // Retrieve the last start position for this object.
         float last_pos_weight = 1.f;
-        if (seam_position == spAligned && this->layer != NULL && this->_seam_position.count(this->layer->object()) > 0) {
+        switch (seam_position) {
-            last_pos = this->_seam_position[this->layer->object()];
+        case spAligned:
+            // Seam is aligned to the seam at the preceding layer.
+            if (this->layer != NULL && this->_seam_position.count(this->layer->object()) > 0) {
+                last_pos = this->_seam_position[this->layer->object()];
+                last_pos_weight = 5.f;
+            }
+            break;
+        case spRear:
+            last_pos = this->layer->object()->bounding_box().center();
+            last_pos.y += coord_t(3. * this->layer->object()->bounding_box().radius());
             last_pos_weight = 5.f;
+            break;
         }
 
         // Insert a projection of last_pos into the polygon.
-		size_t last_pos_proj_idx;
+        size_t last_pos_proj_idx;
-		{
+        {
-			Points::iterator it = project_point_to_polygon_and_insert(polygon, last_pos, 0.1 * nozzle_r);
+            Points::iterator it = project_point_to_polygon_and_insert(polygon, last_pos, 0.1 * nozzle_r);
-			last_pos_proj_idx = it - polygon.points.begin();
+            last_pos_proj_idx = it - polygon.points.begin();
-		}
+        }
         Point last_pos_proj = polygon.points[last_pos_proj_idx];
         // Parametrize the polygon by its length.
         std::vector<float> lengths = polygon_parameter_by_length(polygon);
@@ -661,8 +672,8 @@ GCode::extrude(ExtrusionLoop loop, std::string description, double speed)
         {
             static int iRun = 0;
             SVG svg(debug_out_path("GCode_extrude_loop-%d.svg", iRun ++));
-			if (this->layer->lower_layer != NULL)
+            if (this->layer->lower_layer != NULL)
-				svg.draw(this->layer->lower_layer->slices.expolygons);
+                svg.draw(this->layer->lower_layer->slices.expolygons);
             for (size_t i = 0; i < loop.paths.size(); ++ i)
                 svg.draw(loop.paths[i].as_polyline(), "red");
             Polylines polylines;
@@ -673,9 +684,9 @@ GCode::extrude(ExtrusionLoop loop, std::string description, double speed)
             coord_t delta = scale_(0.5*nozzle_dmr);
             Slic3r::offset(polylines, &polygons, delta);
 //            for (size_t i = 0; i < polygons.size(); ++ i) svg.draw((Polyline)polygons[i], "blue");
-			svg.draw(last_pos, "green", 3);
+            svg.draw(last_pos, "green", 3);
-			svg.draw(polygon.points[idx_min], "yellow", 3);
+            svg.draw(polygon.points[idx_min], "yellow", 3);
-			svg.Close();
+            svg.Close();
         }
         #endif
 
@@ -696,6 +707,7 @@ GCode::extrude(ExtrusionLoop loop, std::string description, double speed)
             last_pos = Point(polygon.bounding_box().max.x, centroid.y);
             last_pos.rotate(fmod((float)rand()/16.0, 2.0*PI), centroid);
         }
+        // Find the closest point, avoid overhangs.
         loop.split_at(last_pos, true);
     }
     

xs/src/libslic3r/PrintConfig.cpp

@@ -618,6 +618,18 @@ PrintConfigDef::PrintConfigDef()
     def->max = 100;
     def->default_value = new ConfigOptionInt(100);
 
+    def = this->add("max_layer_height", coFloats);
+    def->label = "Max";
+    def->tooltip = "This is the highest printable layer height for this extruder, used to cap the variable layer height and support layer height. Maximum recommended layer height is 75% of the extrusion width to achieve reasonable inter-layer adhesion. If set to 0, layer height is limited to 75% of the nozzle diameter.";
+    def->sidetext = "mm";
+    def->cli = "max-layer-height=f@";
+    def->min = 0;
+    {
+        ConfigOptionFloats* opt = new ConfigOptionFloats();
+        opt->values.push_back(0);
+        def->default_value = opt;
+    }
+
     def = this->add("max_print_speed", coFloat);
     def->label = "Max print speed";
     def->tooltip = "When setting other speed settings to 0 Slic3r will autocalculate the optimal speed in order to keep constant extruder pressure. This experimental setting is used to set the highest print speed you want to allow.";
@@ -661,6 +673,18 @@ PrintConfigDef::PrintConfigDef()
     def->max = 100;
     def->default_value = new ConfigOptionInt(35);
 
+    def = this->add("min_layer_height", coFloats);
+    def->label = "Min";
+    def->tooltip = "This is the lowest printable layer height for this extruder and limits the resolution for variable layer height. Typical values are between 0.05 mm and 0.1 mm.";
+    def->sidetext = "mm";
+    def->cli = "min-layer-height=f@";
+    def->min = 0;
+    {
+        ConfigOptionFloats* opt = new ConfigOptionFloats();
+        opt->values.push_back(0.07);
+        def->default_value = opt;
+    }
+
     def = this->add("min_print_speed", coFloat);
     def->label = "Min print speed";
     def->tooltip = "Slic3r will not scale speed down below this speed.";
@@ -942,11 +966,11 @@ PrintConfigDef::PrintConfigDef()
     def->enum_values.push_back("random");
     def->enum_values.push_back("nearest");
     def->enum_values.push_back("aligned");
-//    def->enum_values.push_back("preferred");
+    def->enum_values.push_back("rear");
     def->enum_labels.push_back("Random");
     def->enum_labels.push_back("Nearest");
     def->enum_labels.push_back("Aligned");
-//    def->enum_labels.push_back("Preferred Direction");
+    def->enum_labels.push_back("Rear"); 
     def->default_value = new ConfigOptionEnum<SeamPosition>(spAligned);
 
 #if 0

xs/src/libslic3r/PrintConfig.hpp

@@ -39,7 +39,7 @@ enum SupportMaterialPattern {
 };
 
 enum SeamPosition {
-    spRandom, spNearest, spAligned //, spPreferred
+    spRandom, spNearest, spAligned, spRear
 };
 
 template<> inline t_config_enum_values ConfigOptionEnum<GCodeFlavor>::get_enum_values() {
@@ -85,7 +85,7 @@ template<> inline t_config_enum_values ConfigOptionEnum<SeamPosition>::get_enum_
     keys_map["random"]              = spRandom;
     keys_map["nearest"]             = spNearest;
     keys_map["aligned"]             = spAligned;
-//    keys_map["preferred"]           = spPreferred;
+    keys_map["rear"]                = spRear;
     return keys_map;
 }
 
@@ -404,7 +404,9 @@ class PrintConfig : public GCodeConfig
     ConfigOptionFloat               infill_acceleration;
     ConfigOptionBool                infill_first;
     ConfigOptionInt                 max_fan_speed;
+    ConfigOptionFloats              max_layer_height;
     ConfigOptionInt                 min_fan_speed;
+    ConfigOptionFloats              min_layer_height;
     ConfigOptionFloat               min_print_speed;
     ConfigOptionFloat               min_skirt_length;
     ConfigOptionString              notes;
@@ -461,7 +463,9 @@ class PrintConfig : public GCodeConfig
         OPT_PTR(infill_acceleration);
         OPT_PTR(infill_first);
         OPT_PTR(max_fan_speed);
+        OPT_PTR(max_layer_height);
         OPT_PTR(min_fan_speed);
+        OPT_PTR(min_layer_height);
         OPT_PTR(min_print_speed);
         OPT_PTR(min_skirt_length);
         OPT_PTR(notes);