From fc5be662befcbf973db2f21066b1b1883da7acc8 Mon Sep 17 00:00:00 2001
From: Carl Hetherington <carl@carlh.net>
Date: Thu, 4 Nov 2010 18:05:17 +0000
Subject: [PATCH] Remove incorrect caching of region selection start/end
 points, and always compute them.  I'm pretty sure the slow-down won't be a
 problem in practice.  Fixes #3520.

git-svn-id: svn://localhost/ardour2/branches/3.0@7963 d708f5d6-7413-0410-9779-e7cbd77b26cf
---
 gtk2_ardour/region_selection.cc | 92 ++++++++++-----------------------
 gtk2_ardour/region_selection.h  | 11 +---
 2 files changed, 28 insertions(+), 75 deletions(-)

diff --git a/gtk2_ardour/region_selection.cc b/gtk2_ardour/region_selection.cc
index 16f89e5eab..8ad7502414 100644
--- a/gtk2_ardour/region_selection.cc
+++ b/gtk2_ardour/region_selection.cc
@@ -34,9 +34,6 @@ using namespace PBD;
 RegionSelection::RegionSelection ()
 {
 	RegionView::RegionViewGoingAway.connect (death_connection, MISSING_INVALIDATOR, ui_bind (&RegionSelection::remove_it, this, _1), gui_context());
-
-	_current_start = 0;
-	_current_end = 0;
 }
 
 /** Copy constructor.
@@ -47,9 +44,6 @@ RegionSelection::RegionSelection (const RegionSelection& other)
 {
 	RegionView::RegionViewGoingAway.connect (death_connection, MISSING_INVALIDATOR, ui_bind (&RegionSelection::remove_it, this, _1), gui_context());
 
-	_current_start = other._current_start;
-	_current_end = other._current_end;
-
 	for (RegionSelection::const_iterator i = other.begin(); i != other.end(); ++i) {
 		add (*i);
 	}
@@ -65,9 +59,6 @@ RegionSelection::operator= (const RegionSelection& other)
 
 		clear_all();
 
-		_current_start = other._current_start;
-		_current_end = other._current_end;
-
 		for (RegionSelection::const_iterator i = other.begin(); i != other.end(); ++i) {
 			add (*i);
 		}
@@ -83,8 +74,6 @@ RegionSelection::clear_all()
 {
 	clear();
 	_bylayer.clear();
-	_current_start = 0;
-	_current_end = 0;
 }
 
 /**
@@ -117,14 +106,6 @@ RegionSelection::add (RegionView* rv)
 		return false;
 	}
 
-	if (rv->region()->first_frame() < _current_start || empty()) {
-		_current_start = rv->region()->first_frame();
-	}
-
-	if (rv->region()->last_frame() > _current_end || empty()) {
-		_current_end = rv->region()->last_frame();
-	}
-
 	push_back (rv);
 
 	/* add to layer sorted list */
@@ -156,54 +137,8 @@ RegionSelection::remove (RegionView* rv)
 
 		// remove from layer sorted list
 		_bylayer.remove (rv);
-
-		if (size() == 1) {
-
-			/* this is the last one, so when we delete it
-			   we will be empty.
-			*/
-
-			_current_start = 0;
-			_current_end = 0;
-
-		} else {
-
-			boost::shared_ptr<Region> region ((*r)->region());
-
-			if (region->first_frame() == _current_start) {
-
-				/* reset current start */
-
-				framepos_t ref = max_framepos;
-
-				for (RegionSelection::iterator i = begin (); i != end(); ++i) {
-					if (region->first_frame() < ref) {
-						ref = region->first_frame();
-					}
-				}
-
-				_current_start = ref;
-
-			}
-
-			if (region->last_frame() == _current_end) {
-
-				/* reset current end */
-
-				nframes_t ref = 0;
-
-				for (RegionSelection::iterator i = begin (); i != end(); ++i) {
-					if (region->first_frame() > ref) {
-						ref = region->first_frame();
-					}
-				}
-
-				_current_end = ref;
-			}
-		}
-
+		
 		erase (r);
-
 		return true;
 	}
 
@@ -314,3 +249,28 @@ RegionSelection::involves (const TimeAxisView& tv) const
 	return false;
 }
 
+framepos_t
+RegionSelection::start () const
+{
+	framepos_t s = max_framepos;
+	for (RegionSelection::const_iterator i = begin(); i != end(); ++i) {
+		s = min (s, (*i)->region()->position ());
+	}
+
+	if (s == max_framepos) {
+		return 0;
+	}
+	
+	return s;
+}
+
+framepos_t
+RegionSelection::end_frame () const
+{
+	framepos_t e = 0;
+	for (RegionSelection::const_iterator i = begin(); i != end(); ++i) {
+		e = max (e, (*i)->region()->position () + (*i)->region()->length ());
+	}
+
+	return e;
+}
diff --git a/gtk2_ardour/region_selection.h b/gtk2_ardour/region_selection.h
index c4ad44da37..fd43e4626f 100644
--- a/gtk2_ardour/region_selection.h
+++ b/gtk2_ardour/region_selection.h
@@ -47,15 +47,11 @@ class RegionSelection : public std::list<RegionView*>
 
 	void clear_all();
 
-	nframes_t start () const {
-		return _current_start;
-	}
+	framepos_t start () const;
 
 	/* "end" collides with list<>::end */
 
-	nframes_t end_frame () const {
-		return _current_end;
-	}
+	framepos_t end_frame () const;
 
 	const std::list<RegionView *>& by_layer() const { return _bylayer; }
 	void  by_position (std::list<RegionView*>&) const;
@@ -66,9 +62,6 @@ class RegionSelection : public std::list<RegionView*>
 
 	void add_to_layer (RegionView *);
 
-	nframes_t _current_start; ///< start position for the selection
-	nframes_t _current_end; ///< end position for the selection
-
 	std::list<RegionView *> _bylayer; ///< list of regions sorted by layer
 	PBD::ScopedConnection death_connection;
 };
-- 
2.30.2