[linux-audio-dev] Midi/OSC help - Continuous controllers

[Alfons Adriaensen]

On Wed, Jun 29, 2005 at 10:46:55AM -0400, Paul Coccoli wrote:

> On 6/28/05, Olivier Guilyardi <ml at xung.org> wrote:
>
> > I believe there could exist a library with which :
> > 1 - you instantiate a core object (providing the alsa midi port as an arg)
> > 2 - you "attach" to some widgets : sliders, spin buttons, etc.. (note that this
> > is different from extending (bloating) widgets)
> > 3 - you may call a function to enter the capture-mode
> > 4 - 100 % of this capture-mode is encapsulated by the library : knobs-to-widgets
> > assignations are handled transparently
> > 5 - there is some way to retrieve these assignations to recall them later
> > 
> 
> You seem to really like this idea.  Why don't you just do it and see
> if it works well?  I have an unfounded hunch that it won't, since you
> usually want your GUI running in a lower priority thread.

Yes, and you'd force the widgets to update for each message sent by
a knob, even if there are 1000 such messages per second, which is absurd
and could easily freeze the entire application.

It's also not a general model. What if you want to link to GUIs, or
two HW controllers ?

The association should be done in the 'server' part of the model, i.e.
that part which provides the interface to all controllers and viewers.
In the MVC structure, a GUI is just a controller/viewer as any other.
It does not play any central role.

-- 
FA