make sure Pianoroll background gets the data range set when a region is set

gtk2_ardour/pianoroll.cc

@@ -2651,6 +2651,8 @@ Pianoroll::set_region (std::shared_ptr<ARDOUR::MidiRegion> r)
 		zoom_to_show (timecnt_t (timepos_t (max_extents_scale() * max_zoom_extent ().second.samples())));
 	}
 
+	bg->display_region (*view);
+
 	_update_connection = Timers::rapid_connect (sigc::mem_fun (*this, &Pianoroll::maybe_update));
 }
 

gtk2_ardour/pianoroll_background.cc

@@ -20,6 +20,9 @@
  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  */
 
+#include "ardour/smf_source.h"
+#include "ardour/midi_region.h"
+
 #include "pianoroll.h"
 #include "pianoroll_background.h"
 #include "midi_view.h"
@@ -101,3 +104,11 @@ PianorollMidiBackground::apply_note_range_to_children ()
 		view->apply_note_range (lowest_note(), highest_note());
 	}
 }
+
+void
+PianorollMidiBackground::display_region (MidiView& mv)
+{
+	std::shared_ptr<ARDOUR::SMFSource> smf (std::dynamic_pointer_cast<ARDOUR::SMFSource> (mv.midi_region()->source()));
+	assert (smf);
+	(void) update_data_note_range (smf->model()->lowest_note(), smf->model()->highest_note());
+}

gtk2_ardour/pianoroll_background.h

@@ -49,6 +49,7 @@ class PianorollMidiBackground : public MidiViewBackground
 
 	void set_size (int w, int h);
 	void set_view (MidiView*);
+	void display_region (MidiView&);
 
 	ARDOUR::InstrumentInfo* instrument_info() const;