[LAD] LV2 and parameter interpolation

[David Robillard]

On Mon, 2012-02-06 at 12:55 +0100, Jörn Nettingsmeier wrote:
> On 02/06/2012 12:04 PM, Fons Adriaensen wrote:
> > On Mon, Feb 06, 2012 at 10:33:31AM +0100, Jörn Nettingsmeier wrote:
> >
> >> what i want to avoid is a ramp from default or previous values whenever
> >> the plugin is run for the first time. in that case, i want to have no
> >> ramp and start cold with the control port value.
> >
> > For general purpose processing (as opposed to synthesis) that doesn't
> > matter in practice. Certainly not if the ramp is just one period.
> 
> it might if a DAW deactivates plugins on transport stop, then locates, 
> then re-activates on play - can i be sure this won't happen with any host?
> i certainly don't want my first note to go through a sweep of all plugin 
> controls each time i press "play".

You must not make any assumptions about data across a deactive() and
activate().  There is an infinite chasm of unknown time between those
calls.

> >> can i rely on control port data being available during activate() so
> >> that i can initialize my current values to the control port values?

There is the possibility of a run() pre-roll (when nframes=0) but hosts
are not *required* to do this.  Sounds like you don't need it anyway
(but in general this might need sorting out at some point...)

-dr