Crashes badly with LSP-plugins

[Old Castle]

Hi,

Qtractor crashes when I try to add the LSP-plugins Multi-Sampler x12 DirectOut plugin (CLAP).

Any idea why?

[Rui Nuno Capela]

no idea; care to have a debug build and get a backtrace?

EDIT: i have an idea now: that plugin has no audio ins nor outs; try not to use it in qtractor; use the stereo versions instead, or any other that have at least one plugin audio output.

[Rui Nuno Capela]

fixed in qtractor >= 0.9.33.35git.d01c8d

thanks

[Old Castle]

It worked for me.

[Old Castle]

It may be related, since now all Mixer x4/8/16 Stereo/Mono plugins crash Qtractor.

[Rui Nuno Capela]

you have no use for plugins that present more inputs than audio outputs in qtractor;

in a word: don't use them: they'll never work as intended

if you insist, you may use something like Carla instead.

[Old Castle]

Ok... I don't understand here. So, some plugins from LSP have more audio inputs than audio outputs in qtractor. Why is that? Is the LSP desgin or a Qtractor limitation?

[Rui Nuno Capela]

both.

1. LSP design: plugins that have ins > outs are simply useless in qtractor--don't ever rely on them; they won't ever work as expected anyway; although reasons why the LSP CLAP Mixer x4/8/16 plugins do crash goes beyond my current understanding; just tested the LV2 versions and they do not crash, but the aforementioned rationale still prevails.
2. Qtractor limitation: yes, it only works correctly for a number of audio channels that match the current track or output bus count; anything else will get lost or just non-operational, if not dysfunctional (even though the plugins don't crash).

[Vladimir Sadovnikov]

At least there is CLAP_AUDIO_PORT_IS_MAIN constant that may give a hint to the Host that this audio port should be used as a primary for the track/bus.

[Vladimir Sadovnikov]

@oldcastlehq
Oh, I forgot to ask which format of plugins do you try to load in Qtractor?

[Vladimir Sadovnikov]

@rncbc

plugins that have ins > outs are simply useless in qtractor--don't ever rely on them;

How do you deal with sidechain then?

[Old Castle]

@oldcastlehq Oh, I forgot to ask which format of plugins do you try to load in Qtractor?

CLAP

[Rui Nuno Capela]

How do you deal with sidechain then?

qtractor does not support sidechain scenarios.

[Rui Nuno Capela]

At least there is CLAP_AUDIO_PORT_IS_MAIN constant that may give a hint to the Host that this audio port should be used as a primary for the track/bus.

that was exactly what was there before this later fix: somehow, none of the LSP Multisampler plugins report a single CLAP_AUDIO_PORT_IS_MAIN.

[Vladimir Sadovnikov]

none of the LSP Multisampler plugins report a single CLAP_AUDIO_PORT_IS_MAIN

Hmm, I need to look at this.

[Rui Nuno Capela]

yes you should; I just reverted the said fix, just bcoz surge-xt .clap wouldn't work otherwise, sorry

so... the LSP Multisampler CLAP at least the DirectOut one will keep crashing anyway