disambiguate another use of Rect on OS X

diff --git a/gtk2_ardour/editor_canvas_events.cc b/gtk2_ardour/editor_canvas_events.cc
index be2b5c3de7431802ea0a13006a896111b77f9e56..2f4fe40bcde770c75bc0e273f6cb2de19e118cef 100644 (file)
--- a/gtk2_ardour/editor_canvas_events.cc
+++ b/gtk2_ardour/editor_canvas_events.cc
@@ -163,7 +163,7 @@ bool
 Editor::canvas_scroll_event (GdkEventScroll *event, bool from_canvas)
 {
        if (from_canvas) {
-               boost::optional<Rect> rulers = _time_markers_group->bounding_box();
+               boost::optional<ArdourCanvas::Rect> rulers = _time_markers_group->bounding_box();
                if (rulers && rulers->contains (Duple (event->x, event->y))) {
                        return canvas_ruler_event ((GdkEvent*) event, timecode_ruler, TimecodeRulerItem);
                }