vase mode fix:

* if the object is hollow and has only thin walls loops, the orientation must be enforced on gcode.cpp
 * add extra_perimeters as unwanted setting for spiral vase.
 * add dense infill as unwanted setting for spiral vase.

src/libslic3r/GCode.cpp

@@ -1323,7 +1323,7 @@ void GCode::process_layer(
         m_spiral_vase->enable = enable;
     }
     // If we're going to apply spiralvase to this layer, disable loop clipping
-    m_enable_loop_clipping = ! m_spiral_vase || ! m_spiral_vase->enable;
+    m_enable_loop_clipping = !m_spiral_vase || !m_spiral_vase->enable;
     
     std::string gcode;
 
@@ -2021,6 +2021,10 @@ std::string GCode::extrude_loop(ExtrusionLoop loop, std::string description, dou
     // extrude all loops ccw
     //no! this was decided in perimeter_generator
     bool was_clockwise = false;// loop.make_counter_clockwise();
+    //if spiral vase, we have to ensure that all loops are in the same orientation.
+    if (this->m_config.spiral_vase) {
+        was_clockwise = loop.make_counter_clockwise();
+    }
     
     SeamPosition seam_position = m_config.seam_position;
     if (loop.loop_role() == elrSkirt) 
@@ -2088,7 +2092,6 @@ std::string GCode::extrude_loop(ExtrusionLoop loop, std::string description, dou
         }
         //TODO: ignore the angle penalty if the new point is not in an external path (bot/top/ext_peri)
         for (size_t i = 0; i < polygon.points.size(); ++i) {
-            //std::cout << "check point  @" << unscale(polygon.points[i].x) << ":" << unscale(polygon.points[i].y);
             float ccwAngle = penalties[i];
             if (was_clockwise)
                 ccwAngle = - ccwAngle;

src/libslic3r/PrintConfig.cpp

@@ -3231,8 +3231,10 @@ void DynamicPrintConfig::normalize()
             this->opt<ConfigOptionPercent>("fill_density", true)->value = 0;
             this->opt<ConfigOptionBool>("support_material", true)->value = false;
             this->opt<ConfigOptionInt>("support_material_enforce_layers")->value = 0;
-            this->opt<ConfigOptionBool>("exact_last_layer_height", true)->value  = false;
+            this->opt<ConfigOptionBool>("exact_last_layer_height", true)->value = false;
-            this->opt<ConfigOptionBool>("ensure_vertical_shell_thickness", true)->value  = false;
+            this->opt<ConfigOptionBool>("ensure_vertical_shell_thickness", true)->value = false;
+            this->opt<ConfigOptionBool>("infill_dense", true)->value = false;
+            this->opt<ConfigOptionBool>("extra_perimeters", true)->value = false;
         }
     }
 }
@@ -3390,6 +3392,10 @@ std::string FullPrintConfig::validate()
             return "Spiral vase mode is not compatible with top solid layers";
         if (this->support_material || this->support_material_enforce_layers > 0)
             return "Spiral vase mode is not compatible with support material";
+        if (this->infill_dense)
+            return "Spiral vase mode can only print hollow objects and have no top surface, so you don't need any dense infill";
+        if (this->extra_perimeters)
+            return "Can't make more than one perimeter when spiral vase mode is enabled";
     }
     
     // extrusion widths

src/slic3r/GUI/Tab.cpp

@@ -1228,6 +1228,8 @@ void TabPrint::update()
         && m_config->opt_int("support_material_enforce_layers") == 0
         && m_config->opt_bool("exact_last_layer_height") == false
         && m_config->opt_bool("ensure_vertical_shell_thickness") == false
+        && m_config->opt_bool("infill_dense") == false
+        && m_config->opt_bool("extra_perimeters") == false
         )) {
 		wxString msg_text = _(L("The Spiral Vase mode requires:\n"
 			"- one perimeter\n"
@@ -1236,6 +1238,8 @@ void TabPrint::update()
 			"- no support material\n"
 			"- no ensure_vertical_shell_thickness\n"
 			"- unchecked 'exact last layer height'\n"
+			"- unchecked 'dense infill'\n"
+			"- unchecked 'extra perimeters'\n"
 			"\nShall I adjust those settings in order to enable Spiral Vase?"));
 		auto dialog = new wxMessageDialog(parent(), msg_text, _(L("Spiral Vase")), wxICON_WARNING | wxYES | wxNO);
         is_msg_dlg_already_exist = true;
@@ -1247,7 +1251,9 @@ void TabPrint::update()
 			new_conf.set_key_value("support_material", new ConfigOptionBool(false));
             new_conf.set_key_value("support_material_enforce_layers", new ConfigOptionInt(0));
             new_conf.set_key_value("exact_last_layer_height", new ConfigOptionBool(false));
-			new_conf.set_key_value("ensure_vertical_shell_thickness", new ConfigOptionBool(false));
+            new_conf.set_key_value("ensure_vertical_shell_thickness", new ConfigOptionBool(false));
+            new_conf.set_key_value("infill_dense", new ConfigOptionBool(false));
+            new_conf.set_key_value("extra_perimeters", new ConfigOptionBool(false));
 			fill_density = 0;
 		}
 		else {