Extend a previous region if we click in a MIDI automation lane where there is no region (#4155).

git-svn-id: svn://localhost/ardour2/branches/3.0@12622 d708f5d6-7413-0410-9779-e7cbd77b26cf

1 files changed, 17 insertions, 2 deletions

diff --git a/gtk2_ardour/editor_mouse.cc b/gtk2_ardour/editor_mouse.cc
index 1ce02457fc..011374f951 100644
--- a/gtk2_ardour/editor_mouse.cc
+++ b/gtk2_ardour/editor_mouse.cc
@@ -1003,8 +1003,23 @@ Editor::button_press_handler_1 (ArdourCanvas::Item* item, GdkEvent* event, ItemT
 				AutomationTimeAxisView* atv = dynamic_cast<AutomationTimeAxisView*> (clicked_axisview);
 				assert (atv);
 				if (parent && dynamic_cast<MidiTimeAxisView*> (parent) && atv->show_regions ()) {
-					/* create a MIDI region so that we have somewhere to put automation */
-					_drags->set (new RegionCreateDrag (this, item, parent), event);
+
+					RouteTimeAxisView* p = dynamic_cast<RouteTimeAxisView*> (parent);
+					assert (p);
+					boost::shared_ptr<Playlist> pl = p->track()->playlist ();
+					if (pl->n_regions() == 0) {
+						/* Parent has no regions; create one so that we have somewhere to put automation */
+						_drags->set (new RegionCreateDrag (this, item, parent), event);
+					} else {
+						/* See if there's a region before the click that we can extend, and extend it if so */
+						framepos_t const t = event_frame (event);
+						boost::shared_ptr<Region> prev = pl->find_next_region (t, End, -1);
+						if (!prev) {
+							_drags->set (new RegionCreateDrag (this, item, parent), event);
+						} else {
+							prev->set_length (t - prev->position ());
+						}
+					}
 				} else {
 					/* rubberband drag to select automation points */
 					_drags->set (new EditorRubberbandSelectDrag (this, item), event);