23 Dec
2002
23 Dec
'02
10:02 p.m.
On Tuesday 24 December 2002 00.28, Tim Hockin wrote:
[...]
Random thoughts:
* sys_controls could be per-plugin not per-channel - they really
ARE plugin-global: TEMPO, METER, TIMEBASE, TRANSPORT, etc.
Yes, if we assume that a plugin can only be aware of one timeline at
a time. Probably not a major restriction.
Making
them per-channel means we can have POLYPHONY, VOICE_ON, and SEEK be
sys controls, too.
No, the latter two are *per-voice* - although that basically just
means they take a VVID argument as well.
(Speaking of which, I implemented a VVID manager for Audiality the
other day. "Finished and tested", although I haven't integrated it
yet.)
* This is all designed to take away the extra fields
that aren't
needed for magic controls. Maybe that is a waste of energy. Just
define macros for making them taste like normal controls, and tell
plugin writers to deal with the wasted memory/footprint.
How many fields can actually be eliminated? Can't be many bytes, and
there aren't all that many of these controls. I can't see that it's
worth any special casing to save a few fields per "magic control".
* If they taste like normal controls, we need to flag
them as
system controls.
Why? It should be enough to give them datatype codes of their own, so
no one will get the idea that they're compatible with anything else.
They really ARE special to the
host/sequencer/timeline.
In what way? Indeed, the relation between TEMPO and POSITION is a bit
"odd", but other than that, they're basically just controls used by
the timeline to express musical time.
* MIDI-compatible controls are essentially fixed
controls, too. We
don't want to break those out. But they aren't as 'special' as
these.
There should be no special "MIDI compatible" controls at all, IMHO,
but rather just a standard set of hints. The motivation for those is
really just this "Cable" idea of hosts connecting ranges of controls
automatically. PITCH->PITCH, VELOCITY->VELOCITY etc.
MIDI drivers/converters would just map MIDI CCs to suitable Controls
in the way suggested by the Control hint names. We could have an
official MIDI CC -> Control mapping, if desired, but no actual
references to MIDI in the API.
Anyone have ideas on the cleanest representation?
Well, I still think the cleanest way would be to use the Control
metadata stuff, giving the timeline controls datatype IDs of their
own. No hints needed, I think, as ranges, semantics etc would be
strictly specified in the API anyway.
//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 -'
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