x11: Add EventSequence → touch detail accessor

The ClutterEventSequence structure is a fully opaque type; on X11, it is
just an unsigned integer that gets converted into a pointer, but in the
future it may become a fully fledged data structure.

Obviously, we cannot tell people to just dereference the pointer into an
integer in order to use it, and still retain the ability to change the
type; for this reason, we need a proper accessor function to convert the
EventSequence into a touch detail, to be used with the XInput API.

clutter/clutter.symbols

@@ -1594,6 +1594,7 @@ clutter_x11_add_filter
 clutter_x11_disable_event_retrieval
 clutter_x11_enable_xinput
 clutter_x11_event_get_key_group
+clutter_x11_event_sequence_get_touch_detail
 clutter_x11_filter_return_get_type
 clutter_x11_get_current_event_time
 clutter_x11_get_default_display

clutter/x11/clutter-device-manager-xi2.c

@@ -1098,10 +1098,11 @@ clutter_device_manager_xi2_translate_event (ClutterEventTranslator *translator,
         if (xev->flags & XITouchEmulatingPointer)
           _clutter_event_set_pointer_emulated (event, TRUE);
 
-        CLUTTER_NOTE (EVENT, "touch %s: win:0x%x device:%s (x:%.2f, y:%.2f, axes:%s)",
+        CLUTTER_NOTE (EVENT, "touch %s: win:0x%x device:%s (seq:%d, x:%.2f, y:%.2f, axes:%s)",
                       event->type == CLUTTER_TOUCH_BEGIN ? "begin" : "end",
                       (unsigned int) stage_x11->xwin,
                       event->touch.device->device_name,
+                      GPOINTER_TO_UINT (event->touch.sequence),
                       event->touch.x,
                       event->touch.y,
                       event->touch.axes != NULL ? "yes" : "no");
@@ -1144,9 +1145,10 @@ clutter_device_manager_xi2_translate_event (ClutterEventTranslator *translator,
         if (xev->flags & XITouchEmulatingPointer)
           _clutter_event_set_pointer_emulated (event, TRUE);
 
-        CLUTTER_NOTE (EVENT, "touch update: win:0x%x device:%s (x:%.2f, y:%.2f, axes:%s)",
+        CLUTTER_NOTE (EVENT, "touch update: win:0x%x device:%s (seq:%d, x:%.2f, y:%.2f, axes:%s)",
                       (unsigned int) stage_x11->xwin,
                       event->touch.device->device_name,
+                      GPOINTER_TO_UINT (event->touch.sequence),
                       event->touch.x,
                       event->touch.y,
                       event->touch.axes != NULL ? "yes" : "no");

clutter/x11/clutter-event-x11.c

@@ -375,3 +375,21 @@ clutter_x11_event_get_key_group (const ClutterEvent *event)
 
   return event_x11->key_group;
 }
+
+/**
+ * clutter_x11_event_sequence_get_touch_detail:
+ * @sequence: a #ClutterEventSequence
+ *
+ * Retrieves the touch detail froma #ClutterEventSequence.
+ *
+ * Return value: the touch detail
+ *
+ * Since: 1.12
+ */
+guint
+clutter_x11_event_sequence_get_touch_detail (const ClutterEventSequence *sequence)
+{
+  g_return_val_if_fail (sequence != NULL, 0);
+
+  return GPOINTER_TO_UINT (sequence);
+}

clutter/x11/clutter-x11.h

@@ -140,6 +140,8 @@ Time clutter_x11_get_current_event_time (void);
 
 gint clutter_x11_event_get_key_group (const ClutterEvent *event);
 
+guint clutter_x11_event_sequence_get_touch_detail (const ClutterEventSequence *sequence);
+
 G_END_DECLS
 
 #endif /* __CLUTTER_X11_H__ */

doc/reference/clutter/clutter-sections.txt

@@ -1364,6 +1364,7 @@ clutter_x11_get_input_devices
 clutter_x11_has_xinput
 clutter_x11_enable_xinput
 clutter_x11_event_get_key_group
+clutter_x11_event_sequence_get_touch_detail
 
 <SUBSECTION Private>
 ClutterX11XInputDevice