From 51256ad7c614f07bb7f1cc3cd5e9b1d024048614 Mon Sep 17 00:00:00 2001
From: Paul Davis <paul@linuxaudiosystems.com>
Date: Wed, 7 Jan 2026 09:16:35 -0700
Subject: [PATCH] pianoroll: correctly hide (etc.) automation when switching
 regions

---
 gtk2_ardour/pianoroll_midi_view.cc | 21 +++++++++++++++++++++
 gtk2_ardour/pianoroll_midi_view.h  |  2 ++
 2 files changed, 23 insertions(+)

diff --git a/gtk2_ardour/pianoroll_midi_view.cc b/gtk2_ardour/pianoroll_midi_view.cc
index fcd7d1f95a..70eb46e586 100644
--- a/gtk2_ardour/pianoroll_midi_view.cc
+++ b/gtk2_ardour/pianoroll_midi_view.cc
@@ -465,6 +465,20 @@ PianorollMidiView::have_visible_automation () const
 	return false;
 }
 
+void
+PianorollMidiView::hide_all_automation ()
+{
+	unset_active_automation ();
+
+	for (auto & [parameter,ads] : automation_map) {
+		ads.hide ();
+	}
+
+	automation_map.clear ();
+	delete velocity_display;
+	velocity_display = nullptr;
+}
+
 void
 PianorollMidiView::toggle_visibility (Evoral::Parameter const & param)
 {
@@ -936,3 +950,10 @@ PianorollMidiView::cut_copy_clear_one (AutomationLine& line, ::Selection& select
 		}
 	}
 }
+
+void
+PianorollMidiView::set_region (std::shared_ptr<MidiRegion> mr)
+{
+	MidiView::set_region (mr);
+	hide_all_automation ();
+}
diff --git a/gtk2_ardour/pianoroll_midi_view.h b/gtk2_ardour/pianoroll_midi_view.h
index 9855d0427f..74bf16a7a2 100644
--- a/gtk2_ardour/pianoroll_midi_view.h
+++ b/gtk2_ardour/pianoroll_midi_view.h
@@ -50,6 +50,7 @@ class PianorollMidiView : public MidiView
 
 	~PianorollMidiView();
 
+	void set_region (std::shared_ptr<ARDOUR::MidiRegion>);
 	void set_samples_per_pixel (double);
 	void set_height (double);
 
@@ -61,6 +62,7 @@ class PianorollMidiView : public MidiView
 	void ghost_sync_selection (NoteBase*);
 
 	void toggle_visibility (Evoral::Parameter const & param);
+	void hide_all_automation ();
 	void swap_automation_channel (int);
 	void set_active_automation (Evoral::Parameter const &);
 	bool is_active_automation (Evoral::Parameter const &) const;