Re: [Denemo-devel] Showstopper bug?

[Richard Shann]

Dominic,

Further to this I just tried the git blame command and got this:

git blame -C -L 68,68 src/portmidibackend.c
a03ecf7d (rshann 2012-01-09 18:16:18 +0000 68) return;

Looking up that commit I find this comment:

Implement the pause feature for playback. Note playback via midi backend
is disabled as it continues to update the playback time regardless of
pause.

So it seems that if you re-enable the portmidi backend it will have the
bad effect that during a pause the playback time will continue to get
updated. The playhead will continue to move along the notes, although
the portaudio output is paused.
 So that will be why I disconnected the code. To re-connect, it will
need to use the same sort of code as the portaudio backend to handle
time while pause is in effect.

Richard


On Tue, 2012-05-15 at 09:08 +0100, Richard Shann wrote:
> Dominic,
> when you said on irc #denemo
> > what problem is the return statement in process_midi() (in 
> > portmidibackend.c) supposed to solve? what would happen if i remove it?
> 
> I answered thinking you were referring to the first return statement in 
> process_midi().
> 
> But, now I look further I see the your point - I have put in another
> return to ignore the midi output backend. As the comment says, this is
> because I introduced the pause feature involving handling the time
> differently and I expected the portmidi output code would need altering.
> I haven't got any MIDI output device to test such code, so I don't know
> what it will do without that return statement - perhaps I should simply
> have let it happen and wait for feedback?
> If you can test it I would be most interested to know what happens, it
> can't possibly work complete with Pause, but it could be that it would
> still play. (In a similar vein, you will have noticed that I
> re-connected the non-threaded audio input code for inputting notes from
> a microphone, and it just works; it is safest to disconnect stuff that
> *may* cause problems while developing, but it is always worth trying to
> reconnect it afterwards to see if it does just work anyway).
> 
> Richard
>