Configure skirt start point

src/libslic3r/GCode.cpp

@@ -3425,6 +3425,33 @@ namespace Skirt {
         return skirt_loops_per_extruder_out;
     }
 
+    static Point find_start_point(ExtrusionLoop& loop, float start_angle) {
+        coord_t min_x = std::numeric_limits<coord_t>::max();
+        coord_t max_x = std::numeric_limits<coord_t>::min();
+        coord_t min_y = min_x;
+        coord_t max_y = max_x;
+
+        Points pts;
+        loop.collect_points(pts);
+        for (Point pt: pts) {
+            if (pt.x() < min_x)
+                min_x = pt.x();
+            else if (pt.x() > max_x)
+                max_x = pt.x();
+            if (pt.y() < min_y)
+                min_y = pt.y();
+            else if (pt.y() > max_y)
+                max_y = pt.y();
+        }
+
+        Point center((min_x + max_x)/2., (min_y + max_y)/2.);
+        double r       = center.distance_to(Point(min_x, min_y));
+        double deg     = start_angle * PI / 180;
+        double shift_x = r * std::cos(deg);
+        double shift_y = r * std::sin(deg);
+        return Point(center.x()+shift_x, center.y() + shift_y);
+    }
+
 } // namespace Skirt
 
 // Orca: Klipper can't parse object names with spaces and other spetical characters
@@ -3995,6 +4022,11 @@ LayerResult GCode::process_layer(
                     path.height = layer_skirt_flow.height();
                     path.mm3_per_mm = mm3_per_mm;
                 }
+
+                //set skirt start point location
+                if (first_layer && i==loops.first)
+                    this->set_last_pos(Skirt::find_start_point(loop, layer.object()->config().skirt_start_angle));
+
                 //FIXME using the support_speed of the 1st object printed.
                 gcode += this->extrude_loop(loop, "skirt", m_config.support_speed.value);
             }

src/libslic3r/Preset.cpp

@@ -774,7 +774,7 @@ static std::vector<std::string> s_Preset_print_options {
     "inner_wall_speed", "outer_wall_speed", "sparse_infill_speed", "internal_solid_infill_speed",
     "top_surface_speed", "support_speed", "support_object_xy_distance", "support_interface_speed",
     "bridge_speed", "internal_bridge_speed", "gap_infill_speed", "travel_speed", "travel_speed_z", "initial_layer_speed",
-    "outer_wall_acceleration", "initial_layer_acceleration", "top_surface_acceleration", "default_acceleration", "skirt_loops", "skirt_speed","min_skirt_length", "skirt_distance", "skirt_height", "draft_shield",
+    "outer_wall_acceleration", "initial_layer_acceleration", "top_surface_acceleration", "default_acceleration", "skirt_loops", "skirt_speed","min_skirt_length", "skirt_distance", "skirt_start_angle", "skirt_height", "draft_shield",
     "brim_width", "brim_object_gap", "brim_type", "brim_ears_max_angle", "brim_ears_detection_length", "enable_support", "support_type", "support_threshold_angle", "enforce_support_layers",
     "raft_layers", "raft_first_layer_density", "raft_first_layer_expansion", "raft_contact_distance", "raft_expansion",
     "support_base_pattern", "support_base_pattern_spacing", "support_expansion", "support_style",

src/libslic3r/Print.cpp

@@ -225,6 +225,7 @@ bool Print::invalidate_state_by_config_options(const ConfigOptionResolver & /* n
             || opt_key == "min_skirt_length"
             || opt_key == "draft_shield"
             || opt_key == "skirt_distance"
+            || opt_key == "skirt_start_angle"
             || opt_key == "ooze_prevention"
             || opt_key == "wipe_tower_x"
             || opt_key == "wipe_tower_y"

src/libslic3r/PrintConfig.cpp

@@ -3992,6 +3992,15 @@ void PrintConfigDef::init_fff_params()
     def->mode = comAdvanced;
     def->set_default_value(new ConfigOptionFloat(2));
 
+    def = this->add("skirt_start_angle", coFloat);
+    def->label = L("Skirt start point");
+    def->tooltip = L("Angle from the object center to skirt start point. Zero is the most right position, counter clockwise is positive angle.");
+    def->sidetext = L("°");
+    def->min = -180;
+    def->max = 180;
+    def->mode = comAdvanced;
+    def->set_default_value(new ConfigOptionFloat(-135));
+
     def = this->add("skirt_height", coInt);
     def->label = L("Skirt height");
     //def->label = "Skirt height";

src/libslic3r/PrintConfig.hpp

@@ -1220,6 +1220,7 @@ PRINT_CONFIG_CLASS_DERIVED_DEFINE(
     ((ConfigOptionFloats,             retraction_minimum_travel))
     ((ConfigOptionBools,              retract_when_changing_layer))
     ((ConfigOptionFloat,              skirt_distance))
+    ((ConfigOptionFloat,              skirt_start_angle))
     ((ConfigOptionInt,                skirt_height))
     ((ConfigOptionInt,                skirt_loops))
     ((ConfigOptionFloat,              skirt_speed))

src/slic3r/GUI/ConfigManipulation.cpp

@@ -569,7 +569,7 @@ void ConfigManipulation::toggle_print_fff_options(DynamicPrintConfig *config, co
     
     bool have_skirt = config->opt_int("skirt_loops") > 0;
     toggle_field("skirt_height", have_skirt && config->opt_enum<DraftShield>("draft_shield") != dsEnabled);
-    for (auto el : { "skirt_distance", "draft_shield"})
+    for (auto el : { "skirt_distance", "skirt_start_angle", "draft_shield"})
         toggle_field(el, have_skirt);
     
     bool have_brim = (config->opt_enum<BrimType>("brim_type") != btNoBrim);

src/slic3r/GUI/Plater.cpp

@@ -2770,7 +2770,7 @@ Plater::priv::priv(Plater *q, MainFrame *main_frame)
     , config(Slic3r::DynamicPrintConfig::new_from_defaults_keys({
         "printable_area", "bed_exclude_area", "bed_custom_texture", "bed_custom_model", "print_sequence",
         "extruder_clearance_radius", "extruder_clearance_height_to_lid", "extruder_clearance_height_to_rod",
-		"nozzle_height", "skirt_loops", "skirt_speed","min_skirt_length", "skirt_distance",
+		"nozzle_height", "skirt_loops", "skirt_speed","min_skirt_length", "skirt_distance", "skirt_start_angle",
         "brim_width", "brim_object_gap", "brim_type", "nozzle_diameter", "single_extruder_multi_material", "preferred_orientation",
         "enable_prime_tower", "wipe_tower_x", "wipe_tower_y", "prime_tower_width", "prime_tower_brim_width", "prime_volume",
         "extruder_colour", "filament_colour", "material_colour", "printable_height", "printer_model", "printer_technology",

src/slic3r/GUI/Tab.cpp

@@ -61,7 +61,7 @@ namespace GUI {
 
 #define DISABLE_UNDO_SYS
 
-static const std::vector<std::string> plate_keys = { "curr_bed_type", "first_layer_print_sequence", "first_layer_sequence_choice", "other_layers_print_sequence", "other_layers_sequence_choice", "print_sequence", "spiral_mode"};
+static const std::vector<std::string> plate_keys = { "curr_bed_type", "skirt_start_angle", "first_layer_print_sequence", "first_layer_sequence_choice", "other_layers_print_sequence", "other_layers_sequence_choice", "print_sequence", "spiral_mode"};
 
 void Tab::Highlighter::set_timer_owner(wxEvtHandler* owner, int timerid/* = wxID_ANY*/)
 {
@@ -2321,6 +2321,7 @@ page = add_options_page(L("Others"), "custom-gcode_other"); // ORCA: icon only v
         optgroup->append_single_option_line("skirt_loops");
         optgroup->append_single_option_line("min_skirt_length");
         optgroup->append_single_option_line("skirt_distance");
+        optgroup->append_single_option_line("skirt_start_angle");
         optgroup->append_single_option_line("skirt_height");
         optgroup->append_single_option_line("skirt_speed");
         optgroup->append_single_option_line("draft_shield");
@@ -2789,6 +2790,7 @@ void TabPrintPlate::build()
     auto page = add_options_page(L("Plate Settings"), "empty");
     auto optgroup = page->new_optgroup("");
     optgroup->append_single_option_line("curr_bed_type");
+    optgroup->append_single_option_line("skirt_start_angle");        
     optgroup->append_single_option_line("print_sequence");
     optgroup->append_single_option_line("spiral_mode");
     optgroup->append_single_option_line("first_layer_sequence_choice");
@@ -2837,6 +2839,8 @@ void TabPrintPlate::on_value_change(const std::string& opt_key, const boost::any
             auto plate = dynamic_cast<PartPlate*>(plate_item.first);
             if (k == "curr_bed_type")
                 plate->reset_bed_type();
+            if (k == "skirt_start_angle")
+                plate->config()->erase("skirt_start_angle");
             if (k == "print_sequence")
                 plate->set_print_seq(PrintSequence::ByDefault);
             if (k == "first_layer_sequence_choice")
@@ -2860,6 +2864,10 @@ void TabPrintPlate::on_value_change(const std::string& opt_key, const boost::any
                 bed_type = m_config->opt_enum<BedType>("curr_bed_type");
                 plate->set_bed_type(BedType(bed_type));
             }
+            if (k == "skirt_start_angle") {
+                float angle = m_config->opt_float("skirt_start_angle");
+                plate->config()->set_key_value("skirt_start_angle", new ConfigOptionFloat(angle));
+            }
             if (k == "print_sequence") {
                 print_seq = m_config->opt_enum<PrintSequence>("print_sequence");
                 plate->set_print_seq(print_seq);