Disable touch zoom if pen is active

src/control/tools/StrokeHandler.cpp

@@ -286,6 +286,9 @@ bool StrokeHandler::getPressureMultiplier(GdkEvent* event, double& pressure)
 	}
 
 	// This causes some memory corruption
+	// If touch and pen is active at the same time
+	// Here are random crashes. It cannot be reproduced
+	// without touch and pen at the same time
 //	gdouble* axes = event->button.axes;
 //	gdk_device_get_state(device,
 //						 gtk_widget_get_parent_window(xournal->getWidget()),

src/gui/XournalView.cpp

@@ -49,6 +49,7 @@ XournalView::XournalView(GtkWidget* parent, Control* control)
 	this->margin = 75;
 	this->currentPage = 0;
 	this->lastSelectedPage = -1;
+	this->lastPenAction = 0;
 
 	control->getZoomControl()->addZoomListener(this);
 
@@ -360,11 +361,20 @@ bool XournalView::onKeyReleaseEvent(GdkEventKey* event)
 
 void XournalView::onRealized(GtkWidget* widget, XournalView* view)
 {
+	XOJ_CHECK_TYPE_OBJ(view, XournalView);
+
 	view->setEventCompression(view->getControl()->getSettings()->isEventCompression());
 }
 
 void XournalView::zoom_gesture_begin_cb(GtkGesture* gesture, GdkEventSequence* sequence, XournalView* view)
 {
+	XOJ_CHECK_TYPE_OBJ(view, XournalView);
+
+	if (view->shouldIgnoreTouchEvents())
+	{
+		return;
+	}
+
 	Layout* layout = gtk_xournal_get_layout(view->widget);
 	// Save visible rectangle at beginning of gesture
 	view->visRect_gesture_begin = layout->getVisibleRect();
@@ -379,6 +389,8 @@ void XournalView::zoom_gesture_begin_cb(GtkGesture* gesture, GdkEventSequence* s
 
 void XournalView::zoom_gesture_end_cb(GtkGesture* gesture, GdkEventSequence* sequence, XournalView* view)
 {
+	XOJ_CHECK_TYPE_OBJ(view, XournalView);
+
 	ZoomControl* zoom = view->control->getZoomControl();
 	zoom->zoom_center_x = -1;
 	zoom->zoom_center_y = -1;
@@ -387,6 +399,13 @@ void XournalView::zoom_gesture_end_cb(GtkGesture* gesture, GdkEventSequence* seq
 
 void XournalView::zoom_gesture_scale_changed_cb(GtkGestureZoom* gesture, gdouble scale, XournalView* view)
 {
+	XOJ_CHECK_TYPE_OBJ(view, XournalView);
+
+	if (view->shouldIgnoreTouchEvents())
+	{
+		return;
+	}
+
 	view->setZoom(scale * view->zoom_gesture_begin);
 }
 
@@ -557,14 +576,45 @@ Rectangle* XournalView::getVisibleRect(size_t page)
 
 Rectangle* XournalView::getVisibleRect(XojPageView* redrawable)
 {
+	XOJ_CHECK_TYPE(XournalView);
+
 	return gtk_xournal_get_visible_area(this->widget, redrawable);
 }
 
 GtkContainer* XournalView::getParent()
 {
+	XOJ_CHECK_TYPE(XournalView);
+
 	return this->parent;
 }
 
+/**
+ * A pen action was detected now, therefore ignore touch events
+ * for a short time
+ */
+void XournalView::penActionDetected()
+{
+	XOJ_CHECK_TYPE(XournalView);
+
+	this->lastPenAction = g_get_monotonic_time() / 1000;
+}
+
+/**
+ * If the pen was active a short time before, ignore touch events
+ */
+bool XournalView::shouldIgnoreTouchEvents()
+{
+	XOJ_CHECK_TYPE(XournalView);
+
+	if ((g_get_monotonic_time() / 1000 - this->lastPenAction) < 1000)
+	{
+		// printf("Ignore touch, pen was active\n");
+		return true;
+	}
+
+	return false;
+}
+
 GtkWidget* XournalView::getWidget()
 {
 	XOJ_CHECK_TYPE(XournalView);

src/gui/XournalView.h

@@ -105,6 +105,18 @@ public:
 	Rectangle* getVisibleRect(XojPageView* redrawable);
 
 	GtkContainer* getParent();
+
+	/**
+	 * A pen action was detected now, therefore ignore touch events
+	 * for a short time
+	 */
+	void penActionDetected();
+
+	/**
+	 * If the pen was active a short time before, ignore touch events
+	 */
+	bool shouldIgnoreTouchEvents();
+
 public:
 	// ZoomListener interface
 	void zoomChanged(double lastZoom);
@@ -182,5 +194,10 @@ private:
 	 */
 	int cleanupTimeout;
 
+	/**
+	 * Last Pen action, to ignore touch events within a time frame
+	 */
+	gint64 lastPenAction;
+
 	friend class Layout;
 };

src/gui/widgets/XournalWidget.cpp

@@ -535,11 +535,21 @@ gboolean gtk_xournal_button_release_event(GtkWidget* widget, GdkEventButton* eve
 	return res;
 }
 
+int dummyCounter = 0;
+
 gboolean gtk_xournal_motion_notify_event(GtkWidget* widget, GdkEventMotion* event)
 {
 	GtkXournal* xournal = GTK_XOURNAL(widget);
 	ToolHandler* h = xournal->view->getControl()->getToolHandler();
 
+	// Workaround to detect if the pen is there
+	GdkDevice* device = gdk_event_get_device((GdkEvent*)event);
+	int axesCount = gdk_device_get_n_axes(device);
+	if (axesCount >= 6)
+	{
+		xournal->view->penActionDetected();
+	}
+
 	if (xournal->view->zoom_gesture_active)
 	{
 		return TRUE;
@@ -597,14 +607,6 @@ gboolean gtk_xournal_motion_notify_event(GtkWidget* widget, GdkEventMotion* even
 		}
 	}
 
-	// Workaround to detect if the pen is there
-	GdkDevice* device = gdk_event_get_device((GdkEvent*)event);
-	GdkInputSource deviceType = gdk_device_get_source(device);
-	if (deviceType == GDK_SOURCE_PEN || deviceType == GDK_SOURCE_ERASER)
-	{
-		printf("pen active\n");
-	}
-
 	return false;
 }