Cut: Fixes and improvements for object's context menu

* Disable or delete some menu items, which are inappropriate for cut objects
* For cut objects added menu item "Invalidate cut info" to disconnect related cut parts of initial object
* If just one part is kept after cut performance, than don't apply a cut info for this object.

+ CutGizmo: Fixed selection of the mode
   An object has connectors         -> Connectors mode
   An object doesn't has connectors -> CutPlane mode

src/libslic3r/Model.cpp

@@ -1261,7 +1261,9 @@ void ModelObject::invalidate_cut()
 {
     for (ModelObject* obj : m_model->objects)
         if (obj != this && obj->cut_id.is_equal(this->cut_id))
-            obj->cut_id.ivalidate();
+            obj->cut_id.invalidate();
+    // invalidate own cut_id
+    this->cut_id.invalidate();
 }
 
 void ModelObject::synchronize_model_after_cut()
@@ -1276,6 +1278,10 @@ void ModelObject::synchronize_model_after_cut()
 
 void ModelObject::apply_cut_attributes(ModelObjectCutAttributes attributes)
 {
+    // we don't save cut information, if result will not contains all parts of initial object
+    if (!attributes.has(ModelObjectCutAttribute::KeepUpper) || !attributes.has(ModelObjectCutAttribute::KeepLower))
+        return;
+
     if (cut_id.id().invalid())
         cut_id.init();
     {

src/libslic3r/ObjectID.hpp

@@ -161,7 +161,7 @@ public:
         return *this; 
     }
 
-    void ivalidate() { 
+    void invalidate() { 
         set_invalid_id();
         m_check_sum = 1;
         m_connectors_cnt = 0;

src/slic3r/GUI/GUI_Factories.cpp

@@ -685,6 +685,24 @@ wxMenuItem* MenuFactory::append_menu_item_printable(wxMenu* menu)
     return menu_item_printable;
 }
 
+void MenuFactory::append_menu_item_invalidate_cut_info(wxMenu* menu)
+{
+    const wxString menu_name = _L("Invalidate cut info");
+
+    bool is_cut = obj_list()->has_selected_cut_object();
+
+    auto menu_item_id = menu->FindItem(menu_name);
+    if (menu_item_id != wxNOT_FOUND) {
+        // Delete old menu item if selected object isn't cut
+        if (!is_cut)
+            menu->Destroy(menu_item_id);
+    }
+    else if (is_cut)
+        append_menu_item(menu, wxID_ANY, menu_name, "",
+            [](wxCommandEvent&) { obj_list()->invalidate_cut_info_for_selection(); }, "", menu,
+            []() { return true; }, m_parent);
+}
+
 void MenuFactory::append_menu_items_osx(wxMenu* menu)
 {
     append_menu_item(menu, wxID_ANY, _L("Rename"), "",
@@ -821,6 +839,8 @@ void MenuFactory::append_menu_items_convert_unit(wxMenu* menu, int insert_pos/*
         ModelObjectPtrs objects;
         for (int obj_idx : obj_idxs) {
             ModelObject* object = obj_list()->object(obj_idx);
+            if (object->is_cut())
+                return false;
             if (vol_idxs.empty()) {
                 for (ModelVolume* volume : object->volumes)
                     if (volume_respects_conversion(volume, conver_type))
@@ -1021,6 +1041,7 @@ wxMenu* MenuFactory::object_menu()
     append_menu_item_settings(&m_object_menu);
     append_menu_item_change_extruder(&m_object_menu);
     update_menu_items_instance_manipulation(mtObjectFFF);
+    append_menu_item_invalidate_cut_info(&m_object_menu);
 
     return &m_object_menu;
 }
@@ -1030,6 +1051,7 @@ wxMenu* MenuFactory::sla_object_menu()
     append_menu_items_convert_unit(&m_sla_object_menu, 11);
     append_menu_item_settings(&m_sla_object_menu);
     update_menu_items_instance_manipulation(mtObjectSLA);
+    append_menu_item_invalidate_cut_info(&m_sla_object_menu);
 
     return &m_sla_object_menu;
 }

src/slic3r/GUI/GUI_Factories.hpp

@@ -89,6 +89,7 @@ private:
     wxMenuItem* append_menu_item_change_type(wxMenu* menu);
     wxMenuItem* append_menu_item_instance_to_object(wxMenu* menu);
     wxMenuItem* append_menu_item_printable(wxMenu* menu);
+    void        append_menu_item_invalidate_cut_info(wxMenu *menu);
     void        append_menu_items_osx(wxMenu* menu);
     wxMenuItem* append_menu_item_fix_through_netfabb(wxMenu* menu);
     wxMenuItem* append_menu_item_simplify(wxMenu* menu);

src/slic3r/GUI/GUI_ObjectList.cpp

@@ -2443,9 +2443,41 @@ bool ObjectList::can_split_instances()
     return selection.is_multiple_full_instance() || selection.is_single_full_instance();
 }
 
+bool ObjectList::has_selected_cut_object() const
+{
+    wxDataViewItemArray sels;
+    GetSelections(sels);
+    if (sels.IsEmpty())
+        return false;
+
+    for (wxDataViewItem item : sels) {
+        const int obj_idx = m_objects_model->GetObjectIdByItem(item);
+        if (obj_idx >= 0 && object(obj_idx)->is_cut())
+            return true;
+    }
+
+    return false;
+}
+
+void ObjectList::invalidate_cut_info_for_selection()
+{
+    wxDataViewItemArray sels;
+    GetSelections(sels);
+    if (sels.IsEmpty())
+        return;
+
+    for (wxDataViewItem item : sels) {
+        const int obj_idx = m_objects_model->GetObjectIdByItem(item);
+        if (obj_idx >= 0 && object(obj_idx)->is_cut())
+            object(obj_idx)->invalidate_cut();
+    }
+
+    update_lock_icons_for_model();
+}
+
 bool ObjectList::can_merge_to_multipart_object() const
 {
-    if (printer_technology() == ptSLA)
+    if (printer_technology() == ptSLA || has_selected_cut_object())
         return false;
 
     wxDataViewItemArray sels;

src/slic3r/GUI/GUI_ObjectList.hpp

@@ -277,6 +277,8 @@ public:
     bool                is_splittable(bool to_objects);
     bool                selected_instances_of_same_object();
     bool                can_split_instances();
+    bool                has_selected_cut_object() const;
+    void                invalidate_cut_info_for_selection();
     bool                can_merge_to_multipart_object() const;
     bool                can_merge_to_single_object() const;
 

src/slic3r/GUI/Gizmos/GLGizmoCut.cpp

@@ -1226,6 +1226,7 @@ bool GLGizmoCut3D::update_bb()
         if (CommonGizmosDataObjects::SelectionInfo* selection = m_c->selection_info()) {
             clear_selection();
             m_selected.resize(selection->model_object()->cut_connectors.size(), false);
+            m_connectors_editing = !m_selected.empty();
         }
 
         return true;
@@ -1333,12 +1334,12 @@ void GLGizmoCut3D::adjust_window_position(float x, float y, float bottom_limit)
 
     ImGui::SetWindowPos(ImVec2(x, y), ImGuiCond_Always);
 
-    if (last_h != win_h || last_y != y) {
+    if (!is_approx(last_h, win_h) || !is_approx(last_y, y)) {
         // ask canvas for another frame to render the window in the correct position
         m_imgui->set_requires_extra_frame();
-        if (last_h != win_h)
+        if (!is_approx(last_h, win_h))
             last_h = win_h;
-        if (last_y != y)
+        if (!is_approx(last_y, y))
             last_y = y;
     }
 }
@@ -1773,9 +1774,9 @@ bool GLGizmoCut3D::can_perform_cut() const
     return tbb.contains(m_plane_center);
 }
 
-void GLGizmoCut3D::apply_connectors_in_model(ModelObject* mo, const bool has_connectors, bool &create_dowels_as_separate_object)
+void GLGizmoCut3D::apply_connectors_in_model(ModelObject* mo, bool &create_dowels_as_separate_object)
 {
-    if (has_connectors && m_connector_mode == CutConnectorMode::Manual) {
+    if (m_connector_mode == CutConnectorMode::Manual) {
         clear_selection();
 
         for (CutConnector&connector : mo->cut_connectors) {
@@ -1824,7 +1825,7 @@ void GLGizmoCut3D::perform_cut(const Selection& selection)
         {
             Plater::TakeSnapshot snapshot(wxGetApp().plater(), _L("Cut by Plane"));
             // update connectors pos as offset of its center before cut performing
-            apply_connectors_in_model(mo, has_connectors, create_dowels_as_separate_object);
+            apply_connectors_in_model(mo, create_dowels_as_separate_object);
         }
 
         plater->cut(object_idx, instance_idx, assemble_transform(cut_center_offset) * m_rotation_m,

src/slic3r/GUI/Gizmos/GLGizmoCut.hpp

@@ -225,7 +225,7 @@ private:
     void render_connectors();
 
     bool can_perform_cut() const;
-    void apply_connectors_in_model(ModelObject* mo, const bool has_connectors, bool &create_dowels_as_separate_object);
+    void apply_connectors_in_model(ModelObject* mo, bool &create_dowels_as_separate_object);
     bool cut_line_processing() const;
     void discard_cut_line_processing();
 

src/slic3r/GUI/ObjectDataViewModel.cpp

@@ -1807,6 +1807,7 @@ void ObjectDataViewModel::UpdateLockIcon(const wxDataViewItem& item, bool has_lo
         for (const wxDataViewItem& child : children)
             UpdateLockIcon(child, has_lock);
     }
+    ItemChanged(item);
 }
 
 } // namespace GUI

src/slic3r/GUI/Plater.cpp

@@ -4786,7 +4786,8 @@ bool Plater::priv::can_split(bool to_objects) const
 bool Plater::priv::can_scale_to_print_volume() const
 {
     const BuildVolume::Type type = this->bed.build_volume().type();
-    return !view3D->get_canvas3d()->get_selection().is_empty() && (type == BuildVolume::Type::Rectangle || type == BuildVolume::Type::Circle);
+    return  !sidebar->obj_list()->has_selected_cut_object() &&
+            !view3D->get_canvas3d()->get_selection().is_empty() && (type == BuildVolume::Type::Rectangle || type == BuildVolume::Type::Circle);
 }
 
 bool Plater::priv::layers_height_allowed() const
@@ -4801,16 +4802,19 @@ bool Plater::priv::layers_height_allowed() const
 
 bool Plater::priv::can_mirror() const
 {
-    return get_selection().is_from_single_instance();
+    return !sidebar->obj_list()->has_selected_cut_object() && get_selection().is_from_single_instance();
 }
 
 bool Plater::priv::can_replace_with_stl() const
 {
-    return get_selection().get_volume_idxs().size() == 1;
+    return !sidebar->obj_list()->has_selected_cut_object() && get_selection().get_volume_idxs().size() == 1;
 }
 
 bool Plater::priv::can_reload_from_disk() const
 {
+    if (sidebar->obj_list()->has_selected_cut_object())
+        return false;
+
 #if ENABLE_RELOAD_FROM_DISK_REWORK
     // collect selected reloadable ModelVolumes
     std::vector<std::pair<int, int>> selected_volumes = reloadable_volumes(model, get_selection());
@@ -4939,9 +4943,7 @@ bool Plater::priv::can_increase_instances() const
      || q->canvas3D()->get_gizmos_manager().is_in_editing_mode())
             return false;
 
-    int obj_idx = get_selected_object_idx();
-    return (0 <= obj_idx) && (obj_idx < (int)model.objects.size()) 
-            && !model.objects[obj_idx]->is_cut();
+    return !sidebar->obj_list()->has_selected_cut_object();
 }
 
 bool Plater::priv::can_decrease_instances() const
@@ -4950,9 +4952,7 @@ bool Plater::priv::can_decrease_instances() const
      || q->canvas3D()->get_gizmos_manager().is_in_editing_mode())
             return false;
 
-    int obj_idx = get_selected_object_idx();
-    return (0 <= obj_idx) && (obj_idx < (int)model.objects.size()) && (model.objects[obj_idx]->instances.size() > 1)
-            && !model.objects[obj_idx]->is_cut();
+    return !sidebar->obj_list()->has_selected_cut_object();
 }
 
 bool Plater::priv::can_split_to_objects() const