MidiViewBackground now has a virtual method to access instrument info

gtk2_ardour/midi_streamview.cc

@@ -92,6 +92,17 @@ MidiStreamView::~MidiStreamView ()
 	undisplay_track ();
 }
 
+InstrumentInfo*
+MidiStreamView::instrument_info() const
+{
+	std::shared_ptr<Route> r = _trackview.route();
+	if (!r) {
+		return nullptr;
+	}
+
+	return &r->instrument_info();
+}
+
 void
 MidiStreamView::parameter_changed (string const & param)
 {

gtk2_ardour/midi_streamview.h

@@ -89,6 +89,8 @@ public:
 	void record_layer_check (std::shared_ptr<ARDOUR::Region>, samplepos_t);
 	void set_note_highlight (bool);
 
+	ARDOUR::InstrumentInfo* instrument_info() const;
+
 protected:
 	void setup_rec_box ();
 	void update_rec_box ();

gtk2_ardour/midi_view_background.h

@@ -35,6 +35,10 @@
 
 #include "view_background.h"
 
+namespace ARDOUR {
+	class InstrumentInfo;
+}
+
 namespace ArdourCanvas {
 	class Item;
 	class LineSet;
@@ -117,6 +121,8 @@ class MidiViewBackground : public virtual ViewBackground
 	virtual void set_size (double w, double h) {}
 	PBD::Signal<void()> HeightChanged;
 
+	virtual ARDOUR::InstrumentInfo* instrument_info() const = 0;
+
   protected:
 	bool                      _range_dirty;
 	double                    _range_sum_cache;

gtk2_ardour/pianoroll.cc

@@ -490,6 +490,8 @@ Pianoroll::set_visible_channel (int n)
 		view->set_visible_channel (n);
 		view->swap_automation_channel (n);
 	}
+
+	prh->instrument_info_change ();
 }
 
 void
@@ -3021,3 +3023,13 @@ Pianoroll::shift_midi (timepos_t const & t, bool model)
 
 	view->shift_midi (t, model);
 }
+
+InstrumentInfo*
+Pianoroll::instrument_info () const
+{
+	if (!view || !view->midi_track()) {
+		return nullptr;
+	}
+
+	return &view->midi_track()->instrument_info ();
+}

gtk2_ardour/pianoroll.h

@@ -147,6 +147,8 @@ class Pianoroll : public CueEditor
 	void shift_midi (Temporal::timepos_t const &, bool model);
 	void make_a_region();
 
+	ARDOUR::InstrumentInfo* instrument_info() const;
+
   protected:
 	void load_bindings ();
 	void register_actions ();

gtk2_ardour/pianoroll_background.cc

@@ -66,6 +66,12 @@ PianorollMidiBackground::width() const
 	return _width;
 }
 
+ARDOUR::InstrumentInfo*
+PianorollMidiBackground::instrument_info () const
+{
+	return pianoroll.instrument_info ();
+}
+
 uint8_t
 PianorollMidiBackground::get_preferred_midi_channel () const
 {

gtk2_ardour/pianoroll_background.h

@@ -50,6 +50,8 @@ class PianorollMidiBackground : public MidiViewBackground
 	void set_size (double w, double h);
 	void set_view (MidiView*);
 
+	ARDOUR::InstrumentInfo* instrument_info() const;
+
   protected:
 	MidiView* view;
 	Pianoroll& pianoroll;