Added force_full_scene_refresh parameter to the 3DScene::refresh()

function to force a refresh of all GLVolumes. Currently this hack
is used by the Platter::arrange() function only, and ideally
we should replace this parameter with a smarter 3DScene::refresh()
function, which would check for the transformation matrices as well.

src/slic3r/GUI/3DScene.cpp

@@ -2107,9 +2107,9 @@ void _3DScene::mirror_selection(wxGLCanvas* canvas, Axis axis)
     s_canvas_mgr.mirror_selection(canvas, axis);
 }
 
-void _3DScene::reload_scene(wxGLCanvas* canvas, bool force)
+void _3DScene::reload_scene(wxGLCanvas* canvas, bool refresh_immediately, bool force_full_scene_refresh)
 {
-    s_canvas_mgr.reload_scene(canvas, force);
+    s_canvas_mgr.reload_scene(canvas, refresh_immediately, force_full_scene_refresh);
 }
 
 void _3DScene::load_gcode_preview(wxGLCanvas* canvas, const GCodePreviewData* preview_data, const std::vector<std::string>& str_tool_colors)

src/slic3r/GUI/3DScene.hpp

@@ -644,7 +644,7 @@ public:
 
     static void mirror_selection(wxGLCanvas* canvas, Axis axis);
 
-    static void reload_scene(wxGLCanvas* canvas, bool force);
+    static void reload_scene(wxGLCanvas* canvas, bool refresh_immediately, bool force_full_scene_refresh = false);
 
     static void load_gcode_preview(wxGLCanvas* canvas, const GCodePreviewData* preview_data, const std::vector<std::string>& str_tool_colors);
     static void load_preview(wxGLCanvas* canvas, const std::vector<std::string>& str_tool_colors);

src/slic3r/GUI/GLCanvas3D.cpp

@@ -3767,7 +3767,7 @@ void GLCanvas3D::mirror_selection(Axis axis)
 // 3) SLA support meshes for their respective ModelObjects / ModelInstances
 // 4) Wipe tower preview
 // 5) Out of bed collision status & message overlay (texture)
-void GLCanvas3D::reload_scene(bool force)
+void GLCanvas3D::reload_scene(bool refresh_immediately, bool force_full_scene_refresh)
 {
     if ((m_canvas == nullptr) || (m_config == nullptr) || (m_model == nullptr))
         return;
@@ -3809,7 +3809,7 @@ void GLCanvas3D::reload_scene(bool force)
     glvolumes_new.reserve(m_volumes.volumes.size());
     auto model_volume_state_lower = [](const ModelVolumeState &m1, const ModelVolumeState &m2) { return m1.geometry_id < m2.geometry_id; };
 
-    m_reload_delayed = ! m_canvas->IsShown() && ! force;
+    m_reload_delayed = ! m_canvas->IsShown() && ! refresh_immediately && ! force_full_scene_refresh;
 
     PrinterTechnology printer_technology = wxGetApp().preset_bundle->printers.get_edited_preset().printer_technology();
 
@@ -3866,7 +3866,7 @@ void GLCanvas3D::reload_scene(bool force)
                 if (it != model_volume_state.end() && it->geometry_id == key.geometry_id)
 					mvs = &(*it);
             }
-            if (mvs == nullptr) {
+            if (mvs == nullptr || force_full_scene_refresh) {
                 // This GLVolume will be released.
                 volume->release_geometry();
                 if (! m_reload_delayed)

src/slic3r/GUI/GLCanvas3D.hpp

@@ -824,7 +824,7 @@ public:
 
     void mirror_selection(Axis axis);
 
-    void reload_scene(bool force);
+    void reload_scene(bool refresh_immediately, bool force_full_scene_refresh);
 
     void load_gcode_preview(const GCodePreviewData& preview_data, const std::vector<std::string>& str_tool_colors);
     void load_preview(const std::vector<std::string>& str_tool_colors);

src/slic3r/GUI/GLCanvas3DManager.cpp

@@ -506,11 +506,11 @@ void GLCanvas3DManager::mirror_selection(wxGLCanvas* canvas, Axis axis)
         it->second->mirror_selection(axis);
 }
 
-void GLCanvas3DManager::reload_scene(wxGLCanvas* canvas, bool force)
+void GLCanvas3DManager::reload_scene(wxGLCanvas* canvas, bool refresh_immediately, bool force_full_scene_refresh)
 {
     CanvasesMap::iterator it = _get_canvas(canvas);
     if (it != m_canvases.end())
-        it->second->reload_scene(force);
+        it->second->reload_scene(refresh_immediately, force_full_scene_refresh);
 }
 
 void GLCanvas3DManager::load_gcode_preview(wxGLCanvas* canvas, const GCodePreviewData* preview_data, const std::vector<std::string>& str_tool_colors)

src/slic3r/GUI/GLCanvas3DManager.hpp

@@ -141,7 +141,7 @@ public:
 
     void mirror_selection(wxGLCanvas* canvas, Axis axis);
 
-    void reload_scene(wxGLCanvas* canvas, bool force);
+    void reload_scene(wxGLCanvas* canvas, bool refresh_immediately, bool force_full_scene_refresh = false);
 
     void load_gcode_preview(wxGLCanvas* canvas, const GCodePreviewData* preview_data, const std::vector<std::string>& str_tool_colors);
     void load_preview(wxGLCanvas* canvas, const std::vector<std::string>& str_tool_colors);

src/slic3r/GUI/Plater.cpp

@@ -930,7 +930,7 @@ struct Plater::priv
 
     priv(Plater *q, MainFrame *main_frame);
 
-    void update();
+    void update(bool force_full_scene_refresh = false);
     void select_view(const std::string& direction);
     void update_ui_from_settings();
     ProgressStatusBar* statusbar();
@@ -1144,7 +1144,7 @@ Plater::priv::priv(Plater *q, MainFrame *main_frame)
     q->Layout();
 }
 
-void Plater::priv::update()
+void Plater::priv::update(bool force_full_scene_refresh)
 {
     wxWindowUpdateLocker freeze_guard(q);
     if (get_config("autocenter") == "1") {
@@ -1160,7 +1160,7 @@ void Plater::priv::update()
         // pulls the correct data.
         this->update_background_process();
     }
-    _3DScene::reload_scene(canvas3D, false);
+    _3DScene::reload_scene(canvas3D, false, force_full_scene_refresh);
     preview->reset_gcode_preview_data();
     preview->reload_print();
 
@@ -1662,9 +1662,9 @@ void Plater::priv::arrange()
     // We enable back the arrange button
     _3DScene::enable_toolbar_item(canvas3D, "arrange", can_arrange());
 
-    // FIXME: none of the following seem to work now. (update did the job previously)
+    // Do a full refresh of scene tree, including regenerating all the GLVolumes.
-    // _3DScene::reload_scene(canvas3D, false);
+    //FIXME The update function shall just reload the modified matrices.
-    update();
+    update(true);
 }
 
 void Plater::priv::split_object()