Re: [LMMS-devel] effects support

[Tobias D. <tob...@gm...>]

> > > For instrument tracks, there is an "FX" tab after
> > > the "ARP/CHORD" tab...
> > that's the one annoying me most.
> I knew you wouldn't like that :)
oh, after sleeping a night about it, I actually like it for the same
reasons you gave in your mail (effects are part of synth). this also
has the advantage that the effects are saved in the presets. now we
only should think about how we solve the problem that the tab-texts go
beyond the right side, maybe we should name "Instrument" just "Inst"
or so but that would be less descriptive for newbies... ;-)

> Finally, they can be bypassed, which just adds the
> check to see if they're bypassed as overhead.
yeah, that wasn't my concern but it's good to know ;-)

> Yeah, I need to abstract the effect class, then derive
> ladspaEffect, lmmsEffect, vstEffect...  Anything that
> gets put into an effectChain would have to provide a
> processAudioBuffer and the other LMMS specific
> controls--bypass, wet/dry, and stop-processing
> controls (though the manner in which I'm handling
> unnecessary processing seems open to debate).
hey, you got it!! ;-) and the effect-class is derived from
plugin-class (or an even more specialized sub-class) and thus can be
loaded via existing mechanisms, ain't that cool?! :-) concerning the
"unneccessary processing": what about a check after each processing
whether the effect changed the audio-buffer, i.e. create a local
buffer, copy processing-buffer into it, call processAudioBuffer and
then memcmp() the resulting buf and the local buffer? Of course we
only run this checks at the end of a played note (e.g. when it's
released), otherwise it's probably too much overhead...

> I also think it can.  Here's what I'm thinking.  The
> mixer is an alternative view of the track controls.
> On the left side is a view of the effect rack for
> which ever track is selected.
one question, when do you think a track is selected? or do you mean
fx-channels? I like the way it's done in FL Studio where you have all
fx-channels at the top (side by side), maybe 40x150 pixels in size
containing the description/name of the fx-channel and if you click it,
below the according effect-chain appears. I think this is the general
way I'll make it up in the next days. Above the effect-chain there
could be all the extra-controls for the selected FX-channel. the
fx-channel-labels at the top (where you select the channel) could also
contain a knob for setting the volume of this channel but there
shouldn't be more controls (ok, we could discuss about panning), as
the UI would become too overloaded...

> On the right side are
> the level, panning and whatnot controls for each
> instrumentTrack, sampleTrack, and, here's the exciting
> part, auxBusTrack.
>
> An auxBusTrack is a sub-mixer that mixes just the
> output from the tracks that are attached to it, but it
> also can have an effect rack like the other tracks
> currently have (it's a track so that we can use the
> automation system and make it easier to integrate with
> the mixer).
hmmm?? I don't understand this one, sorry... What we need is a
master-fx-channel in which all fx-channels are routed at the end of
their processing and there you can setup an effect-chain for ALL
instruments (e.g. a general reverb or so as mentioned by stef in
another mail)

> Yeah, we provide a button that brings up a dialog
> where the user can review the current connections,
> disconnect, or assign new connections to any of the
> audioBusTracks that have been defined for the song.  A
> volume control and mute button should also be provided
> for each of the connections to provide control over
> the relative track levels being used as inputs to the
> sub-mixes.
I think a connection-system is too complex, the fx-channel-system with
additional features (which we didn't discuss so far) can do everything
one needs...

But all this is stuff we can do later, first I need to get the
mixer-window up and first I'm trying to simply integrate your
fx-tab-widget as effect-chains for each fx-channel...

toby