Added the possibility to set the maximum length of the detour

src/libslic3r/GCode.cpp

@@ -597,6 +597,12 @@ namespace Slic3r {
 
         result.points.front() = start;
         result.points.back()  = end;
+
+        Line travel(start, end);
+        double max_detour_length scale_(gcodegen.config().avoid_crossing_perimeters_max_detour);
+        if ((max_detour_length > 0) && ((result.length() - travel.length()) > max_detour_length)) {
+            result = Polyline({start, end});
+        }
         if (use_external)
             result.translate(-scaled_origin);
         return result;

src/libslic3r/Preset.cpp

@@ -410,7 +410,7 @@ const std::vector<std::string>& Preset::print_options()
         "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", 
     	"ironing", "ironing_type", "ironing_flowrate", "ironing_speed", "ironing_spacing",
-        "max_print_speed", "max_volumetric_speed",
+        "max_print_speed", "max_volumetric_speed", "avoid_crossing_perimeters_max_detour",
 #ifdef HAS_PRESSURE_EQUALIZER
         "max_volumetric_extrusion_rate_slope_positive", "max_volumetric_extrusion_rate_slope_negative",
 #endif /* HAS_PRESSURE_EQUALIZER */

src/libslic3r/Print.cpp

@@ -71,6 +71,7 @@ bool Print::invalidate_state_by_config_options(const std::vector<t_config_option
     // or they are only notes not influencing the generated G-code.
     static std::unordered_set<std::string> steps_gcode = {
         "avoid_crossing_perimeters",
+        "avoid_crossing_perimeters_max_detour",
         "bed_shape",
         "bed_temperature",
         "before_layer_gcode",

src/libslic3r/PrintConfig.cpp

@@ -180,6 +180,16 @@ void PrintConfigDef::init_fff_params()
     def->mode = comExpert;
     def->set_default_value(new ConfigOptionBool(false));
 
+    def = this->add("avoid_crossing_perimeters_max_detour", coFloat);
+    def->label = L("Avoid crossing perimeters - The max detour lenght");
+    def->category = L("Layers and Perimeters");
+    def->tooltip = L("The maximum detour length for avoid crossing perimeters. "
+                     "If the detour is longer than this value, avoid crossing perimeters is not applied for this path.");
+    def->sidetext = L("mm (zero to disable)");
+    def->min = 0;
+    def->mode = comExpert;
+    def->set_default_value(new ConfigOptionFloat(0.));
+
     def = this->add("bed_temperature", coInts);
     def->label = L("Other layers");
     def->tooltip = L("Bed temperature for layers after the first one. "

src/libslic3r/PrintConfig.hpp

@@ -821,6 +821,7 @@ class PrintConfig : public MachineEnvelopeConfig, public GCodeConfig
 public:
 
     ConfigOptionBool                avoid_crossing_perimeters;
+    ConfigOptionFloat               avoid_crossing_perimeters_max_detour;
     ConfigOptionPoints              bed_shape;
     ConfigOptionInts                bed_temperature;
     ConfigOptionFloat               bridge_acceleration;
@@ -894,6 +895,7 @@ protected:
         this->MachineEnvelopeConfig::initialize(cache, base_ptr);
         this->GCodeConfig::initialize(cache, base_ptr);
         OPT_PTR(avoid_crossing_perimeters);
+        OPT_PTR(avoid_crossing_perimeters_max_detour);
         OPT_PTR(bed_shape);
         OPT_PTR(bed_temperature);
         OPT_PTR(bridge_acceleration);

src/slic3r/GUI/Tab.cpp

@@ -1410,6 +1410,7 @@ void TabPrint::build()
         optgroup->append_single_option_line("extra_perimeters", category_path + "extra-perimeters-if-needed");
         optgroup->append_single_option_line("ensure_vertical_shell_thickness", category_path + "ensure-vertical-shell-thickness");
         optgroup->append_single_option_line("avoid_crossing_perimeters", category_path + "avoid-crossing-perimeters");
+        optgroup->append_single_option_line("avoid_crossing_perimeters_max_detour", category_path + "avoid_crossing_perimeters_max_detour");
         optgroup->append_single_option_line("thin_walls", category_path + "detect-thin-walls");
         optgroup->append_single_option_line("overhangs", category_path + "detect-bridging-perimeters");