Slightly fudged but basically reasonable fix for reports of

playback buffer problems when playing an empty MIDI track
(#4388).


git-svn-id: svn://localhost/ardour2/branches/3.0@10619 d708f5d6-7413-0410-9779-e7cbd77b26cf

1 files changed, 14 insertions, 4 deletions

diff --git a/libs/ardour/midi_diskstream.cc b/libs/ardour/midi_diskstream.cc
index 81217b179a..4f7778e09e 100644
--- a/libs/ardour/midi_diskstream.cc
+++ b/libs/ardour/midi_diskstream.cc
@@ -1400,15 +1400,25 @@ MidiDiskstream::set_align_style_from_io ()
 float
 MidiDiskstream::playback_buffer_load () const
 {
-	return (float) ((double) _playback_buf->read_space()/
-			(double) _playback_buf->capacity());
+	/* For MIDI it's not trivial to differentiate the following two cases:
+	   
+	   1.  The playback buffer is empty because the system has run out of time to fill it.
+	   2.  The playback buffer is empty because there is no more data on the playlist.
+
+	   If we use a simple buffer load computation, we will report that the MIDI diskstream
+	   cannot keep up when #2 happens, when in fact it can.  Since MIDI data rates
+	   are so low compared to audio, just give a pretend answer here.
+	*/
+	
+	return 1;
 }
 
 float
 MidiDiskstream::capture_buffer_load () const
 {
-	return (float) ((double) _capture_buf->write_space()/
-			(double) _capture_buf->capacity());
+	/* We don't report playback buffer load, so don't report capture load either */
+	
+	return 1;
 }
 
 int