Add method to send a song position pointer message

diff --git a/libs/ardour/ardour/session.h b/libs/ardour/ardour/session.h
index a1492246077f7100d507e9b7f4ed11ca766cfc59..9ae67bf6b1744e42bc7c4a652e1db8e0b0352c18 100644 (file)
--- a/libs/ardour/ardour/session.h
+++ b/libs/ardour/ardour/session.h
@@ -813,6 +813,7 @@ class Session : public PBD::StatefulDestructible, public PBD::ScopedConnectionLi
 
        void send_mmc_locate (framepos_t);
        int send_full_time_code (framepos_t);
+       void send_song_position_pointer (framepos_t);
 
        bool step_editing() const { return (_step_editors > 0); }
 

diff --git a/libs/ardour/session_midi.cc b/libs/ardour/session_midi.cc
index 50a7178f1bf3590300740ec4da6cd6be228ca45e..66ad0ccc2a6221776d953d17bf82e1f9eb8e8a38 100644 (file)
--- a/libs/ardour/session_midi.cc
+++ b/libs/ardour/session_midi.cc
@@ -45,6 +45,7 @@
 #include "ardour/midi_ui.h"
 #include "ardour/session.h"
 #include "ardour/slave.h"
+#include "ardour/tempo.h"
 
 #include "i18n.h"
 
@@ -581,6 +582,44 @@ Session::mmc_step_timeout ()
        return true;
 }
 
+/***********************************************************************
+ OUTBOUND SYSTEM COMMON STUFF
+**********************************************************************/
+
+
+void
+Session::send_song_position_pointer (framepos_t t)
+{
+       /* This doesn't account for the Meter's note divisor */
+       if (!_engine.freewheeling()) {
+
+               Timecode::BBT_Time time;
+               bbt_time (t, time);
+
+               const double beats_per_bar = tempo_map().meter_at(t).divisions_per_bar();
+
+               /* Midi Beats in terms of Song Position Pointer is equivalent to total
+                  sixteenth notes at 'time' */
+               const uint32_t midi_beats = 4 * (((time.bars - 1) * beats_per_bar) + time.beats - 1);
+
+               /* can only use 14bits worth */
+               if (midi_beats > 0x3fff) {
+                       return;
+               }
+
+               /* split midi beats into a 14bit value */
+               MIDI::byte msg[3] = {
+                       0xf2, /* MIDI System Common - Song Position Pointer status */
+                       midi_beats & 0x7f,
+                       midi_beats & 0x3f80
+               };
+
+               if (MIDI::Port* port = MIDI::Manager::instance()->midi_clock_output_port()) {
+                       port->midimsg (msg, sizeof (msg), 0);
+               }
+       }
+}
+
 int
 Session::start_midi_thread ()
 {