[CM] Ladspa stuff for snd.

[Kjetil S. Matheussen]

On Fri, 1 Aug 2003, Bill Schottstaedt wrote:

> I added ladspa.scm to the Snd tarball.
>
>  > So to make the above design make sense, the preview function needs
>  > to be fixed properly. And I'm not sure how to do that. I guess
>  > its enough to make a new apply-ladspa c-function that doesnt
>  > store undo or update graphics?
>
> You want to play the sound as processed by the plugin, without editing
> anything?  There are examples of that in rtio.scm, bess.scm, and
> bess1.scm.  Basically you open the DAC and send it arbitrary samples;
> with modern machines, surprisingly complex stuff can work in this mode.
> The only problem is that I have tested that code only in OSS/Linux.
>
I think I have got the playing part to work. The problem was the
apply-ladspa function, which takes a sample reader as argument,
stores undo information and update graphics, before returning.

>  > Unfortunately, I can't find a convenient way to get the number
>  > of audio inputs/outputs a plug-in provides.
>
> I've added struct accessors much as in the xm module:
>

This is just great.

> The plugin functions are callable via ladspa-activate etc -- the list is
> in grfsnd.html (I haven't actually tested these yet -- will write an
> example over the weekend).
>

Fantastic. Thats everything and more than I asked and wished for. Now I'll
make a new and better script. Thank you very much.


--