Hand tracker events are now handled by a fullscreen overlay so that touch points are never 'lost'.

src/areas.py

@@ -69,5 +69,8 @@ class FullscreenArea(RectangularArea):
     def __str__(self):
         return '<FullscreenArea size=(%d, %d)>' % self.get_size()
 
+    def contains(self, x, y):
+        return True
+
     def contains_event(self, event):
         return True

src/trackers/transform.py

@@ -94,6 +94,8 @@ class TransformationTracker(GestureTracker):
     supported_gestures = [RotationGesture, PinchGesture, DragGesture,
                           FlickGesture]
 
+    configurable = ['propagate_events']
+
     def __init__(self, area):
         super(TransformationTracker, self).__init__(area)
 
@@ -105,6 +107,8 @@ class TransformationTracker(GestureTracker):
 
         self.deleted = []
 
+        self.propagate_events = False
+
     def update_centroid(self):
         if not self.points:
             self.centroid = None
@@ -126,7 +130,9 @@ class TransformationTracker(GestureTracker):
     def on_point_down(self, event):
         self.points.append(event.point)
         self.update_centroid()
-        event.stop_propagation()
+
+        if not self.propagate_events:
+            event.stop_propagation()
 
     def on_point_move(self, event):
         point = event.point
@@ -142,7 +148,9 @@ class TransformationTracker(GestureTracker):
             self.points.append(point)
             self.update_centroid()
 
-        event.stop_propagation()
+        if not self.propagate_events:
+            event.stop_propagation()
+
         self.invalidate_points()
         l = len(self.points)
 
@@ -175,7 +183,9 @@ class TransformationTracker(GestureTracker):
                 self.trigger(FlickGesture(event, self.centroid,
                                           self.centroid.translation()))
             self.update_centroid()
-            event.stop_propagation()
+
+            if not self.propagate_events:
+                event.stop_propagation()
 
 
     def invalidate_points(self):

tests/testapp.py

@@ -122,12 +122,6 @@ def create_context_window(w, h, callback):
         cr = area.window.cairo_create()
         draw()
 
-    def update_window():
-        """Synchronize overlay with GTK window."""
-        overlay.set_size(*window.get_size())
-        refresh()
-        return True
-
     def handle_key(win, event):
         """Handle key event. 'f' toggles fullscreen, 'b' toggles bounding
         boxes, 'i' toggles input points, 'q' exits the program."""
@@ -151,9 +145,9 @@ def create_context_window(w, h, callback):
         elif key == 'q':
             quit()
 
-    # Root area (will be synchronized with GTK window)
-    global overlay
-    overlay = mt.RectangularArea(0, 0, w, h)
+    def update_window():
+        refresh()
+        return True
 
     # GTK window
     global window, root
@@ -284,10 +278,16 @@ def on_show(window):
         if draw_touch_objects:
             refresh()
 
+    global screen, overlay
+    screen = mt.FullscreenArea()
+    overlay = mt.FullscreenArea()
+    screen.add_area(root)
+    screen.add_area(overlay)
+
     overlay.on_finger_down(handle_down)
     overlay.on_finger_move(lambda g: draw_touch_objects and refresh())
     overlay.on_finger_up(handle_up)
-    root.add_area(overlay)
+
 
     # Root area rotation leads to rotation of all polygons around the centroid
     def move_to_polygons(g):
@@ -331,7 +331,7 @@ if __name__ == '__main__':
     create_context_window(800, 600, on_show)
 
     # Run multi-touch gesture server in separate thread
-    driver = mt.create_driver(root)
+    driver = mt.create_driver(screen)
     mt_thread = Thread(target=driver.start)
     mt_thread.daemon = True
     mt_thread.start()