From a9e7ce15dbd0f7e92b030f44ab0adb92649c880c Mon Sep 17 00:00:00 2001
From: chousemp3 <cathousemp3@protonmail.com>
Date: Fri, 12 Sep 2025 19:02:07 +0200
Subject: [PATCH] Add MIDI note strumming feature

---
 gtk2_ardour/editing_context.cc |  6 ++++
 gtk2_ardour/midi_view.cc       | 59 ++++++++++++++++++++++++++++++++++
 gtk2_ardour/midi_view.h        |  4 +++
 3 files changed, 69 insertions(+)

diff --git a/gtk2_ardour/editing_context.cc b/gtk2_ardour/editing_context.cc
index c5182fe2d4..95015838b5 100644
--- a/gtk2_ardour/editing_context.cc
+++ b/gtk2_ardour/editing_context.cc
@@ -632,6 +632,9 @@ EditingContext::register_midi_actions (Bindings* midi_bindings, std::string cons
 	ActionManager::register_action (_midi_actions, X_("split-notes-less"), _("Split Selected Notes into less pieces"), sigc::bind (sigc::mem_fun (*this, &EditingContext::midi_action), &MidiView::split_notes_less));
 	ActionManager::register_action (_midi_actions, X_("join-notes"), _("Join Selected Notes"), sigc::bind (sigc::mem_fun (*this, &EditingContext::midi_action), &MidiView::join_notes));
 
+	ActionManager::register_action (_midi_actions, X_("strum-forward"), _("Strum notes forward"), sigc::bind (sigc::mem_fun (*this, &EditingContext::midi_action), &MidiView::strum_notes_forward));
+	ActionManager::register_action (_midi_actions, X_("strum-backward"), _("Strum notes backward"), sigc::bind (sigc::mem_fun (*this, &EditingContext::midi_action), &MidiView::strum_notes_backward));
+
 	ActionManager::register_action (_midi_actions, X_("edit-channels"), _("Edit Note Channels"), sigc::bind (sigc::mem_fun (*this, &EditingContext::midi_action), &MidiView::channel_edit));
 	ActionManager::register_action (_midi_actions, X_("edit-velocities"), _("Edit Note Velocities"), sigc::bind (sigc::mem_fun (*this, &EditingContext::midi_action), &MidiView::velocity_edit));
 
@@ -1940,6 +1943,9 @@ EditingContext::popup_note_context_menu (ArdourCanvas::Item* item, GdkEvent* eve
 		items.back().set_sensitive (false);
 	}
 	items.push_back(MenuElem(_("Transform..."), sigc::bind(sigc::mem_fun(*this, &EditingContext::transform_regions), mvs)));
+	items.push_back (SeparatorElem());
+	items.push_back(MenuElem(_("Strum forward"), sigc::mem_fun(mrv, &MidiView::strum_notes_forward)));
+	items.push_back(MenuElem(_("Strum backward"), sigc::mem_fun(mrv, &MidiView::strum_notes_backward)));
 
 	_note_context_menu.popup (event->button.button, event->button.time);
 }
diff --git a/gtk2_ardour/midi_view.cc b/gtk2_ardour/midi_view.cc
index 79680298cd..a4176800bf 100644
--- a/gtk2_ardour/midi_view.cc
+++ b/gtk2_ardour/midi_view.cc
@@ -5367,3 +5367,62 @@ MidiView::set_visible_channel (int chn, bool clear_selection)
 	}
 }
 
+void
+MidiView::strum_notes (bool forward, bool fine)
+{
+	if (_selection.empty()) {
+		return;
+	}
+
+	start_note_diff_command (_("Strum"));
+
+	Notes notes;
+	selection_as_notelist (notes, false);
+
+	if (notes.size() < 2) {
+		abort_note_diff();
+		return;
+	}
+
+	Temporal::Beats total_offset;
+	Temporal::Beats offset;
+
+	if (fine) {
+		offset = Temporal::Beats::ticks (Temporal::ticks_per_beat / 128);
+	} else {
+		offset = Temporal::Beats::ticks (Temporal::ticks_per_beat / 32);
+	}
+
+	if (forward) {
+		for (auto const & n : notes) {
+			NoteBase* cne = find_canvas_note (n);
+			if (cne) {
+				change_note_time (cne, total_offset, true);
+				total_offset += offset;
+			}
+		}
+	} else { // backward
+		for (auto it = notes.rbegin(); it != notes.rend(); ++it) {
+			NoteBase* cne = find_canvas_note (*it);
+			if (cne) {
+				change_note_time (cne, total_offset, true);
+				total_offset += offset;
+			}
+		}
+	}
+
+	apply_note_diff ();
+}
+
+void
+MidiView::strum_notes_forward ()
+{
+	strum_notes (true, false);
+}
+
+void
+MidiView::strum_notes_backward ()
+{
+	strum_notes (false, false);
+}
+
diff --git a/gtk2_ardour/midi_view.h b/gtk2_ardour/midi_view.h
index b3befd5da0..0b4dcd5756 100644
--- a/gtk2_ardour/midi_view.h
+++ b/gtk2_ardour/midi_view.h
@@ -431,7 +431,11 @@ class MidiView : public virtual sigc::trackable, public LineMerger
 
 	void quantize_selected_notes ();
 
+	void strum_notes_forward ();
+	void strum_notes_backward ();
+
   protected:
+	void strum_notes (bool forward, bool end);
 	friend class MidiRubberbandSelectDrag;
 	friend class MidiVerticalSelectDrag;
 	friend class NoteDrag;