1) Perspective camera set as default camera type

2) Camera type selection added to Preferences dialog

src/slic3r/GUI/AppConfig.cpp

@@ -73,8 +73,8 @@ void AppConfig::set_defaults()
     if (get("custom_toolbar_size").empty())
         set("custom_toolbar_size", "100");
 
-    if (get("camera_type").empty())
-        set("camera_type", "1");
+    if (get("use_perspective_camera").empty())
+        set("use_perspective_camera", "1");
 
     // Remove legacy window positions/sizes
     erase("", "main_frame_maximized");

src/slic3r/GUI/Camera.cpp

@@ -31,7 +31,7 @@ Camera::Camera()
     : phi(45.0f)
     , requires_zoom_to_bed(false)
     , inverted_phi(false)
-    , m_type(Ortho)
+    , m_type(Perspective)
     , m_target(Vec3d::Zero())
     , m_theta(45.0f)
     , m_zoom(1.0)
@@ -61,20 +61,17 @@ void Camera::set_type(EType type)
     if (m_type != type)
     {
         m_type = type;
-
-        wxGetApp().app_config->set("camera_type", std::to_string(m_type));
+        wxGetApp().app_config->set("use_perspective_camera", (m_type == Perspective) ? "1" : "0");
         wxGetApp().app_config->save();
     }
 }
 
 void Camera::set_type(const std::string& type)
 {
-    if (!type.empty() && (type != "1"))
-    {
-        unsigned char type_id = atoi(type.c_str());
-        if (((unsigned char)Ortho < type_id) && (type_id < (unsigned char)Num_types))
-            set_type((Camera::EType)type_id);
-    }
+    if (type == "1")
+        set_type(Perspective);
+    else
+        set_type(Ortho);
 }
 
 void Camera::select_next_type()

src/slic3r/GUI/Camera.hpp

@@ -49,6 +49,7 @@ public:
     EType get_type() const { return m_type; }
     std::string get_type_as_string() const;
     void set_type(EType type);
+    // valid values for type: "0" -> ortho, "1" -> perspective
     void set_type(const std::string& type);
     void select_next_type();
 

src/slic3r/GUI/GLCanvas3D.cpp

@@ -3312,6 +3312,9 @@ void GLCanvas3D::handle_sidebar_focus_event(const std::string& opt_key, bool foc
 
 void GLCanvas3D::update_ui_from_settings()
 {
+    m_camera.set_type(wxGetApp().app_config->get("use_perspective_camera"));
+    m_dirty = true;
+
 #if ENABLE_RETINA_GL
     const float orig_scaling = m_retina_helper->get_scale_factor();
 

src/slic3r/GUI/GUI_Preview.cpp

@@ -313,6 +313,12 @@ Preview::~Preview()
     }
 }
 
+void Preview::set_as_dirty()
+{
+    if (m_canvas != nullptr)
+        m_canvas->set_as_dirty();
+}
+
 void Preview::set_number_extruders(unsigned int number_extruders)
 {
     if (m_number_extruders != number_extruders)

src/slic3r/GUI/GUI_Preview.hpp

@@ -110,6 +110,8 @@ public:
     wxGLCanvas* get_wxglcanvas() { return m_canvas_widget; }
     GLCanvas3D* get_canvas3d() { return m_canvas; }
 
+    void set_as_dirty();
+
     void set_number_extruders(unsigned int number_extruders);
     void set_canvas_as_dirty();
     void set_enabled(bool enabled);

src/slic3r/GUI/Plater.cpp

@@ -1774,7 +1774,7 @@ Plater::priv::priv(Plater *q, MainFrame *main_frame)
     set_current_panel(view3D);
 
     // updates camera type from .ini file
-    camera.set_type(get_config("camera_type"));
+    camera.set_type(get_config("use_perspective_camera"));
 }
 
 void Plater::priv::update(bool force_full_scene_refresh)
@@ -1842,10 +1842,8 @@ void Plater::priv::update_ui_from_settings()
     //     $self->{buttons_sizer}->Layout;
     // }
 
-#if ENABLE_RETINA_GL
     view3D->get_canvas3d()->update_ui_from_settings();
     preview->get_canvas3d()->update_ui_from_settings();
-#endif
 }
 
 ProgressStatusBar* Plater::priv::statusbar()

src/slic3r/GUI/Preferences.cpp

@@ -28,7 +28,7 @@ void PreferencesDialog::build()
             m_icon_size_sizer->ShowItems(boost::any_cast<bool>(value));
             this->layout();
         }
-	};
+    };
 
 	// TODO
 //    $optgroup->append_single_option_line(Slic3r::GUI::OptionsGroup::Option->new(
@@ -97,7 +97,7 @@ void PreferencesDialog::build()
 	option = Option (def,"show_incompatible_presets");
 	m_optgroup->append_single_option_line(option);
 
-	// TODO: remove?
+    // TODO: remove?
 	def.label = L("Use legacy OpenGL 1.1 rendering");
 	def.type = coBool;
 	def.tooltip = L("If you have rendering issues caused by a buggy OpenGL 2.0 driver, "
@@ -117,6 +117,13 @@ void PreferencesDialog::build()
 	m_optgroup->append_single_option_line(option);
 #endif
 
+    def.label = L("Use perspective camera");
+    def.type = coBool;
+    def.tooltip = L("If enabled, use perspective camera. If not enabled, use orthographic camera.");
+    def.set_default_value(new ConfigOptionBool{ app_config->get("use_perspective_camera") == "1" });
+    option = Option(def, "use_perspective_camera");
+    m_optgroup->append_single_option_line(option);
+
 	def.label = L("Use custom size for toolbar icons");
 	def.type = coBool;
 	def.tooltip = L("If enabled, you can change size of toolbar icons manually.");