Add shortcut key O

Toggle render flat shading

docs/shortcuts.rst

@@ -72,6 +72,10 @@ Keyboard
 +----------------------+--------------------------------------------------------------------------+
 | F                    | Bring the part widget of current hovered part to visible area            |
 +----------------------+--------------------------------------------------------------------------+
+| W                    | Toggle render wireframe                                                  |
++----------------------+--------------------------------------------------------------------------+
+| O                    | Toggle render flat shading                                               |
++----------------------+--------------------------------------------------------------------------+
 
 Mouse
 ======

src/documentwindow.cpp

@@ -857,6 +857,10 @@ DocumentWindow::DocumentWindow() :
         m_modelRenderWidget->toggleWireframe();
     });
     
+    connect(graphicsWidget, &SkeletonGraphicsWidget::shortcutToggleFlatShading, [=]() {
+        Preferences::instance().setFlatShading(!Preferences::instance().flatShading());
+    });
+
     connect(graphicsWidget, &SkeletonGraphicsWidget::zoomRenderedModelBy, m_modelRenderWidget, &ModelWidget::zoom);
 
     connect(graphicsWidget, &SkeletonGraphicsWidget::addNode, m_document, &Document::addNode);

src/shortcuts.cpp

@@ -48,4 +48,5 @@ void initShortCuts(QWidget *widget, SkeletonGraphicsWidget *graphicsWidget)
     defineKey(Qt::Key_W, &SkeletonGraphicsWidget::shortcutToggleWireframe);
     defineKey(Qt::Key_F, &SkeletonGraphicsWidget::shortcutCheckPartComponent);
     defineKey(Qt::Key_C, &SkeletonGraphicsWidget::shortcutChamferedOrNotSelectedPart);
+    defineKey(Qt::Key_O, &SkeletonGraphicsWidget::shortcutToggleFlatShading);
 }

src/skeletongraphicswidget.h

@@ -417,6 +417,7 @@ signals:
     void shortcutToggleWireframe();
     void partComponentChecked(QUuid partId);
     void showOrHideAllComponents();
+    void shortcutToggleFlatShading();
 public:
     SkeletonGraphicsWidget(const SkeletonDocument *document);
     std::map<QUuid, std::pair<SkeletonGraphicsNodeItem *, SkeletonGraphicsNodeItem *>> nodeItemMap;