Re: [Denemo-devel] Release 0.9.4

[Richard Shann]

On Fri, 2012-06-15 at 03:54 +0200, Dominic Sacré wrote:
> Hi Richard,
> 
> On Saturday 09 June 2012 15:30:20 Richard Shann wrote:
> > I have checked in a fix for the threading bug in the default build
> > which Dominic pointed out. I have tested the new fix and can report
> > that it fixes a tendency for the playhead to freeze during playback.
> 
> My first attempt to fix this issue was pretty much identical to the change 
> you committed. It fixed the most obvious threading/realtime problems, but 
> I still see some weird glitches with score/playhead drawing that weren't 
> there before.
> 
> Is there a reason to trigger page_viewport() directly from the event queue 
> code (and potentially multiple times, once for each event)? Why not do 
> this somewhere in queue_thread_func(), like all other GUI updates during 
> playback?

Sorry to be so long replying - partly because I am so unfamiliar with
the code (my memory being rather short-term ...) that I don't know the
answer. I didn't ever really get to grips with "what is happening when"
in this code - I started off analysing it following the alsa backend
code only to find that the portaudio backend works rather differently -
portaudio (IIRC) providing interrupts (or possibly it is just another
thread, not explicitly started by us) which progress the time.

I haven't seen any playhead glitches now, but I still heard the
(horrendous) blurting out of everything (?) before Play From Cursor
command. I put the ? there because I am not sure quite what is being
emitted, but a lot of notes at once. Perhaps just what was buffered
between one step and the next of the command getting going?

Richard


> 
> 
> Dominic