[LAD] minimal LV2

[Paul Davis]

On Sun, Jun 13, 2010 at 8:59 AM,  <fons at kokkinizita.net> wrote:

> In fact, I don't see how something like automation 'touch'
> can be provided without race conditions just by letting the
> host intercepting the DSP - GUI communication consisting of
> get/set messages for control port values. Specific support
> is required to do this in any glitch-free way.

supporting touch specifically requires 2 things:

 a) a user interface that has a distinct gesture for both the start
       of a touch and its end
 b) an explicit way to convey the use of this gesture to a
      control object

when using the mouse, we get button press and release events, which
satisfy both (a) and (b). when using external hardware controllers,
many lack anything that can satisfy (a). those that do make things
quite complex - for example there is a tascam controller which sends 2
different MIDI CC's when you move a fader, one to indicate the
onset+end of a touch, and another to signal actual fader moves. this
works well if you have a design that takes this sort of thing into
account, but is horrible otherwise.

> I tried to see if/how this works today using Ardour 2.8.9
> and the Calf compressor, but didn't get that far: just
> using automation 'play' with the plugin GUI open crashes
> both Ardour and the external GUI (memory corruption detected
> by glibc).

i have seen quite a few reports recently that involve the Calf
plugins, most of them not so great (i..e crashes etc). i have some
suspicions that they do GUI operations from an illegal thread.

--p


>
> Ciao,
>
> --
> FA
>
> O tu, che porte, correndo si ?
> E guerra e morte !
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