From 5cebd64924942fab51ed7dcaaffa0553195dc24f Mon Sep 17 00:00:00 2001
From: Robin Gareus <robin@gareus.org>
Date: Thu, 27 Jan 2022 19:56:10 +0100
Subject: [PATCH] Fix fit tracks

The track-height change needs to be applied so that
vertical_adjustment max range is set correctly.
Otherwise vertical_adjustment.set_value() may fail
or scroll to the wrong position.

In 5b3eacd4219 `redisplay_track_views()` was moved from
EditorRoutes to Editor. The call was delegated to the idle
thread, potentially collecting multiple calls before performing
the update.

This resulted in "Fit selection" to set the y-offset before the
height-change was applied.
---
 gtk2_ardour/editor.cc        | 18 ++++++++++++++++++
 gtk2_ardour/editor.h         |  5 ++++-
 gtk2_ardour/editor_canvas.cc |  3 +++
 gtk2_ardour/editor_ops.cc    |  3 +++
 4 files changed, 28 insertions(+), 1 deletion(-)

diff --git a/gtk2_ardour/editor.cc b/gtk2_ardour/editor.cc
index 2f555041be..2085ff11d7 100644
--- a/gtk2_ardour/editor.cc
+++ b/gtk2_ardour/editor.cc
@@ -5600,6 +5600,22 @@ Editor::queue_redisplay_track_views ()
 	}
 }
 
+void
+Editor::process_redisplay_track_views ()
+{
+	if (_tvl_redisplay_connection.connected ()) {
+		_tvl_redisplay_connection.disconnect ();
+		redisplay_track_views ();
+	}
+}
+
+void
+Editor::redisplay_track_views_now ()
+{
+	_tvl_redisplay_connection.disconnect ();
+	redisplay_track_views ();
+}
+
 void
 Editor::resume_route_redisplay ()
 {
@@ -5882,6 +5898,8 @@ Editor::redisplay_track_views ()
 		return false;
 	}
 
+	_tvl_redisplay_on_resume = false;
+
 	TrackViewStripableSorter cmp;
 	track_views.sort (cmp);
 
diff --git a/gtk2_ardour/editor.h b/gtk2_ardour/editor.h
index 874a85b927..371f05cc61 100644
--- a/gtk2_ardour/editor.h
+++ b/gtk2_ardour/editor.h
@@ -1236,8 +1236,11 @@ private:
 	TrackViewList get_tracks_for_range_action () const;
 
 	Gtk::VBox list_vpacker;
+
 	void queue_redisplay_track_views ();
-	bool redisplay_track_views ();
+	void process_redisplay_track_views ();
+	void redisplay_track_views_now ();
+	bool redisplay_track_views (); // do not call this directly, use above wrappers
 
 	bool             _tvl_no_redisplay;
 	bool             _tvl_redisplay_on_resume;
diff --git a/gtk2_ardour/editor_canvas.cc b/gtk2_ardour/editor_canvas.cc
index 1a59859ddd..83ec521fce 100644
--- a/gtk2_ardour/editor_canvas.cc
+++ b/gtk2_ardour/editor_canvas.cc
@@ -957,6 +957,9 @@ Editor::ensure_time_axis_view_is_visible (TimeAxisView const & track, bool at_to
 		return;
 	}
 
+	/* apply any pending [height] changes */
+	process_redisplay_track_views ();
+
 	/* compute visible area of trackview group, as offsets from top of
 	 * trackview group.
 	 */
diff --git a/gtk2_ardour/editor_ops.cc b/gtk2_ardour/editor_ops.cc
index b4223327ca..129f1171e4 100644
--- a/gtk2_ardour/editor_ops.cc
+++ b/gtk2_ardour/editor_ops.cc
@@ -8506,6 +8506,9 @@ Editor::fit_tracks (TrackViewList & tracks)
 		}
 	}
 
+	/* apply height changes, so that scrolling works */
+	process_redisplay_track_views ();
+
 	/*
 	   set the controls_layout height now, because waiting for its size
 	   request signal handler will cause the vertical adjustment setting to fail