diff --git a/MapperGLCanvas.cpp b/MapperGLCanvas.cpp
index 1f4badd..b0322ad 100644
--- a/MapperGLCanvas.cpp
+++ b/MapperGLCanvas.cpp
@@ -30,10 +30,23 @@ MapperGLCanvas::MapperGLCanvas(MainWindow* mainWindow, QWidget* parent, const QG
     _shapeGrabbed(false), // comment out?
     _shapeFirstGrab(false), // comment out?
     _displayControls(true),
-    _stickyVertices(true)
+    _stickyVertices(true),
+    _zoomFactor(8)
 {
 }
 
+void MapperGLCanvas::setZoomFactor(int zoom)
+{
+  qDebug() << zoom << endl;
+  if (zoom < 1)
+    zoom = 1; // the closest we can get is 1:1
+  if (zoom != _zoomFactor) {
+    _zoomFactor = zoom;
+    update();
+    updateGeometry();
+  }
+}
+
 void MapperGLCanvas::initializeGL()
 {
   //qDebug() << "initializeGL" << endl;
@@ -45,10 +58,11 @@ void MapperGLCanvas::initializeGL()
 
 void MapperGLCanvas::resizeGL(int width, int height)
 {
+  qDebug() << "Resize: " << width << " " << height << " at zoom " << _zoomFactor << endl;
   glViewport(0, 0, width, height);
   glMatrixMode (GL_PROJECTION);
   glLoadIdentity ();
-  glOrtho (
+  glOrtho(
     0.0f, (GLfloat) width, // left, right
     (GLfloat) height, 0.0f, // bottom, top
     -1.0, 1.0f);
@@ -220,11 +234,13 @@ void MapperGLCanvas::mouseMoveEvent(QMouseEvent* event)
 
 void MapperGLCanvas::keyPressEvent(QKeyEvent* event)
 {
-  Q_UNUSED(event);
-//  std::cout << "Key pressed" << std::endl;
+  qDebug() << "Key pressed" << endl;
 //  int xMove = 0;
 //  int yMove = 0;
-//  switch (event->key()) {
+  switch (event->key()) {
+  case Qt::Key_Equal: setZoomFactor(zoomFactor()+1); break;
+  case Qt::Key_Minus: setZoomFactor(zoomFactor()-1); break;
+  }
 //  case Qt::Key_Tab:
 //    if (event->modifiers() & Qt::ControlModifier)
 //      switchImage( (Common::getCurrentSourceId() + 1) % Common::nImages());
diff --git a/MapperGLCanvas.h b/MapperGLCanvas.h
index 8ca39db..ebda0c4 100644
--- a/MapperGLCanvas.h
+++ b/MapperGLCanvas.h
@@ -37,6 +37,7 @@ class MainWindow;
 class MapperGLCanvas: public QGLWidget
 {
   Q_OBJECT
+  Q_PROPERTY(int zoomFactor READ zoomFactor WRITE setZoomFactor);
 
 public:
   MapperGLCanvas(MainWindow* mainWindow, QWidget* parent = 0, const QGLWidget* shareWidget = 0);
@@ -54,6 +55,9 @@ public:
   bool displayControls() const { return _displayControls; }
   bool stickyVertices() const { return _stickyVertices; }
 
+  void setZoomFactor(int zoom);
+  int zoomFactor() const { return _zoomFactor; }
+
 protected:
   void initializeGL();
   void resizeGL(int width, int height);
@@ -78,6 +82,7 @@ private:
   bool _shapeFirstGrab;
   bool _displayControls;
   bool _stickyVertices;
+  int _zoomFactor;
 
 signals:
   void shapeChanged(Shape*);