18 Dec
2002
18 Dec
'02
6:56 a.m.
On Wed, Dec 18, 2002 at 11:22:44 +0100, David Olofson wrote:
It's not very hard to do for basic stuff, and it
means many plugins
won't need any internal filtering at all.
Unlikly. Most plugins will only render the control values ever 32 samples
(say) and then will just use linear sections between those.
I think providing all that specification is a mistake, its quite complex
and will not be usefull most of the time.
Many effects will make this audible, and thus, will
need to implement
filtering internally anyway. Splines can probably eliminate this in
most cases.
We should probably try it though. Anyone around here has real
experience with this?
Splines have some unfortunate side effects, like excursions, which make
them only suitable for a small number of cases. Also the calcuation cost
means they have to be used sparingly.
The place the're most useful is where you have high bandwidth, low rate of
change values, eg. in internal ringbuffer pointers. You wouldn't want to
use them on external controls very often.
Also, remember that most of the time the controls are going to come
(ultimatly) from the user moving a slider around (etiher real or GUI) its
not easy to generate good splines from that data. Ramps are much more
practical, and more convienient for the DSP programmer.
- Steve