Re: changing the number of params
Re: changing the number of params
- Subject: Re: changing the number of params
- From: Marc Poirier <email@hidden>
- Date: Wed, 11 Jun 2003 17:09:20 -0500 (CDT)
On Tue, 10 Jun 2003, Pierre-Jean Camillieri wrote:
>
It seems to me that handling parameters' list via "properties"
>
(kAudioUnitProperty_ParameterList) lets me be able to change at any time
>
the number of parameters my AU declares. Am I right with that?
>
If yes, how does a host which has recorded automation react
>
(generally...)? Does it checks which parameters are still there to
>
continue automating them? Or does it consider that such a property
>
change may mean that automation is no more valid for this plug, and
>
discard automation?
I think that you are correct that you can change the number of parameters
(or anything about the parameters) at any time as long as you post
PropertyChanged notification so that listeners are made aware of the
change, but I think that worrying about parameter automation is jumping
ahead a bit. The bigger problem is that hosts aren't listening. At least
last I checked (went through a bunch of host apps and looked at what they
installed property listeners for), a lot of stuff that you would hope that
hosts would install listeners on, no one is installing. It's a really
great and powerful facility of the AU API that in my opinion is being
woefully under-supported by host apps.
In case any host makers are listening ;), my personal list of properties
that I think are most important to listen to are:
kAudioUnitProperty_Latency
This one is *critical* if your host provides latency compenation!
Yet, last I checked, Spark is the only host that installs a listener
(much appreciated, Sven!).
kAudioUnitProperty_ParameterList
kAudioUnitProperty_ParameterInfo
In my opinion, any host that provides any interfacing with AU parameters
aside from the GenericAUView or custom AUViews should install listeners on
these and react to any changes.
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