1 files changed, 4 insertions, 0 deletions
diff --git a/ppapi/c/ppb_input_event.h b/ppapi/c/ppb_input_event.h
index 957694c..8a73279 100644
--- a/ppapi/c/ppb_input_event.h
+++ b/ppapi/c/ppb_input_event.h
@@ -475,6 +475,10 @@ struct PPB_MouseInputEvent {
    *
    * @return The change in position of the mouse, relative to the previous
    * position.
+   *
+   * TODO(yzshen): This feature hasn't been supported yet. The returned value is
+   * always (0, 0) for system-generated mouse events (which are passed through
+   * the <code>HandleInputEvent</code>).
    */
   struct PP_Point (*GetMovement)(PP_Resource mouse_event);
 };