Undo Command to restore position of vertices moved by mouse or arrow key

Commands.cpp

@@ -22,3 +22,29 @@ void AddShapesCommand::redo()
       m_mainWindow->addMappingItem(currentId);
     }
 }
+
+
+MoveVertexCommand::MoveVertexCommand(MapperGLCanvas *mapperGLCanvas, Shape *shape, int activeVertex, const QPointF &point, QUndoCommand *parent) :
+  QUndoCommand(parent)
+{
+  m_mapperGLCanvas = mapperGLCanvas;
+  m_shape = shape;
+  m_activeVertex = activeVertex;
+  newPosition = point;
+
+  oldPosition = m_shape->getVertex(m_activeVertex);
+}
+
+void MoveVertexCommand::undo()
+{
+  m_shape->setVertex(m_activeVertex, oldPosition);
+  m_mapperGLCanvas->update();
+  emit m_mapperGLCanvas->shapeChanged(m_mapperGLCanvas->getCurrentShape());
+}
+
+void MoveVertexCommand::redo()
+{
+  m_shape->setVertex(m_activeVertex, newPosition);
+  m_mapperGLCanvas->update();
+  emit m_mapperGLCanvas->shapeChanged(m_mapperGLCanvas->getCurrentShape());
+}

Commands.h

@@ -24,6 +24,7 @@
 
 #include <QUndoCommand>
 #include "MainWindow.h"
+#include "MapperGLCanvas.h"
 
 class AddShapesCommand : public QUndoCommand
 {
@@ -39,4 +40,22 @@ private:
 
 };
 
+class MoveVertexCommand : public QUndoCommand
+{
+public:
+  MoveVertexCommand(MapperGLCanvas *mapperGLCanvas, Shape *shape, int activeVertex, const QPointF &point, QUndoCommand *parent = 0);
+  void undo();
+  void redo();
+
+signals:
+  void shapeChanged(Shape*);
+
+private:
+  MapperGLCanvas *m_mapperGLCanvas;
+  Shape *m_shape;
+  int m_activeVertex;
+  QPointF newPosition, oldPosition;
+
+};
+
 #endif /* COMMANDS_H_ */

MainWindow.h

@@ -374,6 +374,9 @@ public:
   void removeCurrentPaint();
   void removeCurrentMapping();
 
+  // Use the same undoStack for whole program
+  QUndoStack* getUndoStack() { return undoStack; }
+
   void startFullScreen();
   bool setOscPort(QString portNumber);
   bool setOscPort(int portNumber);

MapperGLCanvas.cpp

@@ -21,6 +21,7 @@
 #include "MapperGLCanvas.h"
 
 #include "MainWindow.h"
+#include "Commands.h"
 
 MapperGLCanvas::MapperGLCanvas(MainWindow* mainWindow, QWidget* parent, const QGLWidget * shareWidget)
   : QGLWidget(QGLFormat(QGL::SampleBuffers), parent, shareWidget),
@@ -202,10 +203,9 @@ void MapperGLCanvas::mouseMoveEvent(QMouseEvent* event)
       // Stick to vertices.
       if (stickyVertices())
         glueVertex(shape, &p);
-      shape->setVertex(_activeVertex, p);
 
-      update();
-      emit shapeChanged(getCurrentShape());
+      // Enable to Undo and Redo when mouse move the position of vertices
+      getMainWindow()->getUndoStack()->push(new MoveVertexCommand(this, shape, _activeVertex, p));
     }
   }
   else if (_shapeGrabbed)
@@ -268,9 +268,8 @@ void MapperGLCanvas::keyPressEvent(QKeyEvent* event)
       break;
     }
     // TODO: this will always be called even if no arrow key has been pressed (small performance issue).
-    shape->setVertex(_activeVertex, p);
-    update();
-    emit shapeChanged(getCurrentShape());
+    // Enable to Undo and Redo when arrow keys move the position of vertices
+    getMainWindow()->getUndoStack()->push(new MoveVertexCommand(this, shape, _activeVertex, p));
   }
 
   // Defer unhandled keys to parent.