From 582661dbd0c25cab3e62446e4a2b1f55d15d4a12 Mon Sep 17 00:00:00 2001
From: Paul Davis <paul@linuxaudiosystems.com>
Date: Wed, 30 Mar 2022 23:08:38 -0600
Subject: [PATCH] as an experiment, prevent redisplay of (MIDI) regions during
 trimming

This doesn't actually work right now because of a conflicting design in MidiRegionView, but
could be promising. Or it might be reverted
---
 gtk2_ardour/editor_drag.cc | 3 +++
 gtk2_ardour/editor_drag.h  | 5 ++++-
 2 files changed, 7 insertions(+), 1 deletion(-)

diff --git a/gtk2_ardour/editor_drag.cc b/gtk2_ardour/editor_drag.cc
index b57f684e42..1f20a26198 100644
--- a/gtk2_ardour/editor_drag.cc
+++ b/gtk2_ardour/editor_drag.cc
@@ -3110,6 +3110,7 @@ TrimDrag::start_grab (GdkEvent* event, Gdk::Cursor*)
 
 	for (list<DraggingView>::const_iterator i = _views.begin(); i != _views.end(); ++i) {
 		i->view->region()->suspend_property_changes ();
+		suspenders.push_back (RegionView::DisplaySuspender (*i->view));
 	}
 }
 
@@ -3352,6 +3353,8 @@ TrimDrag::finished (GdkEvent* event, bool movement_occurred)
 	for (list<DraggingView>::const_iterator i = _views.begin(); i != _views.end(); ++i) {
 		i->view->region()->resume_property_changes ();
 	}
+
+	suspenders.clear ();
 }
 
 void
diff --git a/gtk2_ardour/editor_drag.h b/gtk2_ardour/editor_drag.h
index 769a6103de..9b7d6fcfd3 100644
--- a/gtk2_ardour/editor_drag.h
+++ b/gtk2_ardour/editor_drag.h
@@ -27,6 +27,7 @@
 #define __gtk2_ardour_editor_drag_h_
 
 #include <list>
+#include <vector>
 
 #include <gdk/gdk.h>
 #include <stdint.h>
@@ -41,6 +42,7 @@
 #include "mouse_cursors.h"
 #include "editing.h"
 #include "track_selection.h"
+#include "region_view.h"
 
 namespace ARDOUR {
 	class Location;
@@ -65,7 +67,6 @@ class TimeAxisView;
 class MidiTimeAxisView;
 class Drag;
 class NoteBase;
-class RegionView;
 class TimeAxisView;
 class RouteTimeAxisView;
 class RegionSelection;
@@ -819,6 +820,8 @@ private:
 
 	bool _preserve_fade_anchor;
 	bool _jump_position_when_done;
+
+	std::vector<RegionView::DisplaySuspender> suspenders;
 };
 
 /** Meter marker drag */