[linux-audio-dev] Plugin APIs (again)

David Olofson david at olofson.net
Fri Dec 13 05:22:00 UTC 2002


On Friday 13 December 2002 03.07, Tim Hockin wrote:
[...]
> > How about a mixer with variable insert count? There are several
> > ways to implement that, but I can't think of one that doesn't
> > require either that dreaded "link" feature, or an extra level of
> > "grouping"...
>
> I prefer not to tie the model to hardware like that:  I prefer to
> think of the insert effects as coming before the mixer in the
> chain.  I think it's just simpler.

Well, yes; that was a bad example, since you actually *have* to 
either place the inserts before the mixer, or *host* them, since 
otherwise, you'll have one buffer's worth of delay for each insert. 
*heh* If you really need an input section for the mixer, it'll have 
to be implemented as a separate plugin, so you can put the inserts 
between that and the mixer plugin.


> > So, you basically have a bunch of control channel descriptions
> > and a bunch of io channel descriptions, and then the host can
> > test for valid combinations of those when adding new channels?
>
> That's what I was saying.  I'm not sure it's really useful.
>
> I need to digest the rest of this email.  I'll have a new version
> of the header with most of what we've been discussing in one form
> or another hopefully tonight.  Then we can keep banging out
> details.

Ok.

I'm not sure about the "variable numbers of Bays" thing, but it does 
cover things like adding extra inputs on a Channel, *even* when 
inputs come in stereo pairs, 5.1 sets and the like. You'd have a Bay 
Template for such a group of Ports, and then you can tell the plugin 
how many you want, within the limits specified in the Channel 
Template. (Most plugins will probably hardcode it, but here, it *can* 
be dynamic - on a per-Channel basis.)

Anyway, I'll keep working on the event system, I think. (Although I 
have to work some for money as well... *heh*)

Right now, I'm thinking about interpolation and ramp events. I have 
an idea about something better than linear, that can be handled like 
linear by the lazy receiver. Might work - or not; remains to see.


//David Olofson - Programmer, Composer, Open Source Advocate

.- The Return of Audiality! --------------------------------.
| Free/Open Source Audio Engine for use in Games or Studio. |
| RT and off-line synth. Scripting. Sample accurate timing. |
`---------------------------> http://olofson.net/audiality -'
.- M A I A -------------------------------------------------.
|    The Multimedia Application Integration Architecture    |
`----------------------------> http://www.linuxdj.com/maia -'
   --- http://olofson.net --- http://www.reologica.se ---



More information about the Linux-audio-dev mailing list