Subject: Re: [linux-audio-dev] Laaga "default" audio I/O hooks
From: Paul Davis (pbd_AT_Op.Net)
Date: Sat Jul 21 2001 - 08:24:58 EEST
>I realized what the problem really is and what the answer really is, akin to a
>real modular studio setup. The default audio I/O "hooking" should be done
>with a patchbay client. That is, a client that has pairs of ports like "audio
>output 1" and "audio output to driver 1" which are tied together (zero copy).
>The client itself does nothing, it only supplies the ports. Only the engine
>and/or the driver(s) should be modified to connect to the patchbay's driver
>ports at startup. After this, every detail of the problem can be addressed
>using the plain current Laaga API. Isn't that nice!
Yes, its a really wonderful proof of concept.
>This makes the "alias" interface unnecessary. The Laaga apps can now connect
>to "Patchbay:audio input 1" etc. for audio input and "Patchbay:audio output 1"
>etc. for audio output. The clients that want to "hook" to the system default
>audio inputs or outputs can wire themselves to "Patchbay:audio output to
>driver 1" etc. or "Patchbay:audio input from driver 1" etc.
Not quite sure about those names, but the point is well made. However,
I don't think this will quite work in the way you think. If the
patchbay client has tied "out 1" to "output to driver 1", then "out1"
is an input port (other clients send data there) and "output to driver
1" is an output port (other clients read data from it). hence, no
other client can connect their own output streams to this 2nd port.
but from looking at your source, i think its just your description
here that is a little inaccurate, and the system you've designed
should work well.
>Now I hacked together the code for the patchbay client, but as usual, I cannot
>test it :) Interested parties can fetch it from
>http://iem.kug.ac.at/~jams/laaga-patchbay.tgz
looks OK, though:
1) is this supposed to be a plugin or an external process?
2) you don't need to cleanup ports or anything else before
calling laaga_client_close (). it takes care of all
that for you.
--p
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