Stubbed out load_file, some work on add to call load_file().

Added some comments for canvas2D.

src/GUI/Plater.cpp

@@ -109,8 +109,27 @@ Plater::Plater(wxWindow* parent, const wxString& title, std::shared_ptr<Settings
 }
 void Plater::add() {
     Log::info(LogChannel, L"Called Add function");
+
+    auto& start_object_id = this->object_identifier;
+    const auto& input_files{open_model(this, *(this->settings), wxTheApp->GetTopWindow())};
+    for (const auto& f : input_files) {
+        Log::info(LogChannel, (wxString(L"Calling Load File for ") + f).ToStdWstring());
+        this->load_file(f);
+    }
+
+    // abort if no objects actually added.
+    if (start_object_id == this->object_identifier) return;
+
+    // save the added objects
+   
+    // get newly added objects count
+
 }
 
+std::vector<int> Plater::load_file(const wxString& file) {
+    return std::vector<int>();
+    
+}
 
 }} // Namespace Slic3r::GUI
 

src/GUI/Plater.hpp

@@ -44,14 +44,19 @@ private:
 
     bool processed {false};
 
-    std::vector<PlaterObject> objects {};
+    std::vector<PlaterObject> objects {}; //< Main object vector.
+
+    size_t object_identifier {0U}; //< Counter for adding objects to Slic3r
 
     std::stack<UndoOperation> undo {}; 
     std::stack<UndoOperation> redo {}; 
 
     wxNotebook* preview_notebook {new wxNotebook(this, -1, wxDefaultPosition, wxSize(335,335), wxNB_BOTTOM)};
 
-    Plate2D* canvas2D {};
+    Plate2D* canvas2D {}; //< 2D plater canvas
+
+    /// Handles the actual load of the file from the dialog handoff.
+    std::vector<int> load_file(const wxString& file);
 
     const std::string LogChannel {"GUI_Plater"}; //< Which log these messages should go to.