Re: AU Hosting and Persistence Questions
Re: AU Hosting and Persistence Questions
- Subject: Re: AU Hosting and Persistence Questions
- From: Carsten Gehle <email@hidden>
- Date: Thu, 24 Oct 2002 00:08:20 +0200
On Wednesday, October 23, 2002, at 09:56 PM, Bill Stewart wrote:
We have a growing body of code that is RELYING on the fields that are
already used by the AU's class info, so if you are doing anything with
the
class info data you must support the existing keys or you'll have
problems -
I guarantee that!
OK, for now I am saving the whole property list and check the
appropriate properties before setting a ClassInfo. Do I have to do
anything more on the host side?
As for the Factory Preset and class info... I think its a mistake to
associate a factory preset with saved state of an AU.
OK - I set the AU to a preset. Then I tweak one of the parameters -
the AU
does NOT update its knowledge that it is no longer in a preset pure
state.
Then you save it - then you restore it, thinking that your state was a
preset, but it isn't, its been modified. That is why we thought the
best
course of action is to make the assumption that:
(1) ANY saved state is a user-preset state (ie. We don't save the
factory
preset setting - but we save the current state of the AU)
(2) When a unit has its class info set, it is now in a user preset
state...
OK, so a preset is used to setup an AUs state. Then, thinking of
load/save and undo/redo, I do not understand why the selected preset is
part of the AU's state and especially why the AU is showing the
selected preset to the user. If I had a state based undo/redo
implementation and the user chose a preset for the MatrixReverb (using
Apple's generic UI) and hits 'Undo' the parameters will change
correctly, but the UI will display a 'user-preset'. If the user now
chooses 'Redo', the parameters will be correct again, but the preset
will remain a 'user-preset'.
So, if I understood correctly, the UI for the presets should be a pull
down menu instead of a pop up, even if the AU knows about the 'last
selected preset', and the host should never be interested in getting
the current preset number, right?
BTW: I assume that the preset UI is indented to be provided by the
host, correct?
Thanks,
Carsten
_______________________________________________
coreaudio-api mailing list | email@hidden
Help/Unsubscribe/Archives:
http://www.lists.apple.com/mailman/listinfo/coreaudio-api
Do not post admin requests to the list. They will be ignored.