Distrho Plugins crash in Muse

MusE is a DAW for Linux with both MIDI and Audio editing. https://muse-sequencer.github.io

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Re: Distrho Plugins crash in Muse

Post by spamatica »

I'm on Kubuntu 18.04, can't get any sound out of either Red Zeppelin or Black Pearl when launching from MusE, however if I use CarlaRack they work just fine.

As artofmusic mentions clicking in the plugin gui should show a red animation together with the sound. When instantiated from MusE there is neither.
Further more, I see there's an idleInterface extension which this plugin seems to use and I recall we have had issues with similar functionality for VST instruments. Not that it's related but might be same kind of problem.
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Re: Distrho Plugins crash in Muse

Post by Tim E. Real »

Yes, exactly, I pointed that out Robin G. that the idle is in fact being called continuously,
and yet there's no animations.
He suggested I try other plugins such as SimpleScope. It does not respond either.
I see that both plugins seem to be built upon the same kit(s).
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Re: Distrho Plugins crash in Muse

Post by Tim E. Real »

Observation: In QTractor, when first adding the plugin to a track, notice how the animations are also not working -
unless you activate the plugin (the green activate light in QTractor).
The animations only work when the plugin is activated.

When de-activated, the behaviour in QTractor is exactly the same as we see in MusE right now.

But... we DO activate the plugin.
I traced it and saw that lilv_instance_activate() is being called, and that lilv_instance_deactivate() was not being called too soon.
This is immediately after creating of the plugin itself, long before any GUI is created or shown.
(I posted that test to Robin.)

I dunno guys, I'm gonna lay my money on something to do with that freakin' activation.
It's just too much of a coincidence that it behaves exactly the same in QTractor when deactivated as we see
in MusE where it is supposed to be activated.

I, or somebody, should try to bust in there and somehow re-activate the plugin after the GUI has shown.
Stay tooned... I'm super real busy with other things and libel to drop out at any time for long periods, but those are my thoughts for now.

[Edit:] It's pretty clear to me that the idle interface is working. Otherwise there would be nothing there and I think
the other animations and tooltips and so on would not work. I tested by removing the idle calls and of course, like other plugins
which need it, nothing was shown at all. It's pretty clear also that the very first time idle is called is an important one,
this has been observed now and before where it's all blank until that very first call.
And that first call seems fussy with some plugins, I've seen it. Witness the Distrho plugins (which this thread is about) -
where I just had to remove something from our all-important very first idle call to make them work.
Anyway, more evidence of my activation theory. Idle seems to be working.

[Edit:] I suppose it could be the plugin's idle interface after all, and although various other aspects of it are working,
really it's something deep down that depends on our systems that is making it not respond yet actually play for one of us.
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Re: Distrho Plugins crash in Muse

Post by artofmusic »

Sorry, for the long-overdue response, I think I might be on to something in regards to why helm LV2 is crashing. If you check the image attachment below you'll see what my observations are. Klangfalter and others have the same situation.
In order to reproduce what I have on the image open Muse and go to:
1) Settings --> Global Settings --> GUI Behavior --> (Scroll to the bottom of Behavior) --> Select Ask always (for LV2 UI Open behavior) --> Apply --> Ok --> (Restart Muse)
2) Right Click on the arranger window --> Add Synth --> LV2 synths --> Helm LV2-0 (Underneath the port section) --> Right Click on Helm LV2-0 --> Left Click show native gui
3) now you will have two options like the image attached below.
I know this is a hack and we need a way to fix how Muse handles embedding of external UI's, but this can help someone trying to use Muse figure out the UI to use and reduce crashing the DAW. Another proposition is to allow the native GUI to embed itself instead of allowing Muse to embed it using QtWidgets. Hope this helps.
Workaround for the LV2 UI crashing issue.
Workaround for the LV2 UI crashing issue.
gui_options.png (145.23 KiB) Viewed 33 times
Git Build from March 24 2019
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Re: Distrho Plugins crash in Muse

Post by Tim E. Real »

Sorry for the verrry late reply.
I think I observed this recently, independent of reading or remembering this post.
I recall Helm worked well with one UI but not the other.

Slowly but surely I'll try to investigate. Occasionally I must wade through some serious debugging of LV2 code.
Last week I fixed LV2 worker extensions. Yay. So hang in there.
Big modules like that tend to fade from memory, and when revisited... ugh.
Andrew D. wrote most of it, but hey, after some time I can't even remember my own code!

I just want to pop in and comment, thanks to Andrew for allowing us to choose the UI 8)
I remember when he was toying with it and decided to make a default so not to pester the user each time opening.

I have a desire to make it more clear to the user of fresh-installed MusE that in fact they can choose the native UI
without pestering them each time or one time, without having to discover this ability in Settings.

What say we add a menu item to that right-click context menu (the one with "show gui", "show native gui", and "Presets" sub-menu).
Let's call the new menu item "Change native UI".
When clicked, we force the 'Select gui type' popup menu to open, and the user then chooses a new UI.
Andrew gave us the ability to 'Ask once' along with 'Use first available' and 'Ask always' in Settings.
So, we can put those three choices right there in the 'Select gui type' popup menu !

[ Edit: ] Let's just put all of that stuff in a sub-menu of the original right-click context menu, underneath the "show native gui" item.
IOW No more 'Select gui type' popup menu.

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Re: Distrho Plugins crash in Muse

Post by Tim E. Real »

Whee. For the first time I just found the equivalent of MusE's 'Use first available', 'Ask once, 'Ask always'
in the Plugins tab of QTractor's Options dialog. Which then enables the equivalent of our 'Select gui type' popup menu.

And... Guess what...

Tested Helm with external UI in QTractor:
Using latest Helm git.
Helm with external UI fails there as well.
In fact it does not open at all !

It seems the ball is in Helm's court now ?
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