Re: Clarification of Write-only AudioUnit parameters
Re: Clarification of Write-only AudioUnit parameters
- Subject: Re: Clarification of Write-only AudioUnit parameters
- From: Urs Heckmann <email@hidden>
- Date: Tue, 3 Dec 2002 09:03:38 +0100
Am Dienstag, 03.12.02, um 03:08 Uhr (Europe/Berlin) schrieb Brian
Willoughby:
Of course, if the Host App caches all write-only values locally, then
it
becomes easier to provide controls for these parameters. Local caching
effectively turns a write-only parameter into a write+read parameter.
The one
thing to watch out for is that a write+read control differs from a
read+write
control in that the current value of a write+read is not known until
it has
been written at least once, while a read+write can be queried
initially before
being displayed.
Read-only controls are already common, such as VU meters, and
non-editable
TextFields. It's only truly write-only controls that need a new look
in order
to provide intuitive feedback to users.
Hi, I think your interpretation is indeed too close to physical world
:-)
The typical write-only control is a labelled button that doesn't alter
its appearence after being clicked. If you do not add another control,
i.e. a display, or means like opening/closing windows, you wouldn't
notice any change.
There is no reason why one should assume a write-only parameter
shouldn't be readable by any part of code. A read-only parameter is
_written_ by the dsp (i.e. a RMS value for a VU meter) and can be read
by the user interface. In my understanding, a write-only parameter is
written by the UI and _read_ by the dsp-part.
Some examples for write-only parameter applications:
A sample-load button: The GUI starts a filebrowser or something and
tells the dsp to be prepared to load a new sample, for whatever any
notification is needed before loading.
A development purpose button: I use to add a button to development
versions that write current _readable_ parameters to the console or a
file preformattet in C++ for copy/paste into preset setup code.
A preset independent state button: Your AU provides modes for special
situations that shouldn't be treated like common parameters. I.e. a
"Master Quality Mode" button that you push before you mix down a single
AU instrument track with highest quality (and worst cpu performance).
This time you'd provide feedback and have a on/off toggle or such.
Of course, you're not limited to using buttons, but I think these are
the most obvious write-only controls...
Chees,
;) Urs
-----------
urs heckmann
email@hidden
www.u-he.com
-----------
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