Speed up automation lane removal with many ctrl points6.0-rc2

Deleting the group first, directly removes child items
without triggering Canvas::item_changed() for every item.

This significantly speeds up closing sessions (or deleting tracks)
with lots of automation events.

1 files changed, 7 insertions, 2 deletions

diff --git a/gtk2_ardour/automation_line.cc b/gtk2_ardour/automation_line.cc
index 34d59ef581..802c29cf01 100644
--- a/gtk2_ardour/automation_line.cc
+++ b/gtk2_ardour/automation_line.cc
@@ -131,8 +131,13 @@ AutomationLine::AutomationLine (const string&                              name,
 
 AutomationLine::~AutomationLine ()
 {
-	vector_delete (&control_points);
-	delete group;
+	delete group; // deletes child items
+
+	for (std::vector<ControlPoint *>::iterator i = control_points.begin(); i != control_points.end(); i++) {
+		(*i)->unset_item ();
+		delete *i;
+	}
+	control_points.clear ();
 
 	if (_our_time_converter) {
 		delete _time_converter;