When i change some knobs in yoshimi LV2 plugin - Ardour does not get notified, and when session closed it does not ask user to save changes. This is minor nuisance, as saving session manually before closing works just fine. (user have to remember to do that)
OK. I'm not clear on this (LV2 is not my strong point). Are you saying that other plugins do make such a notification?
Yes. Almost all Lv2 plugins i have tried do. For example TAL-Noizemaker (from distrho-ports project), most of Calf-studio-gear plugins, MDA piano, etc.
Only some plugins does not do that, for example: calf-fluindsynth, yoshimi, zynaddsubfx (but zyn has further ploblems with loading its saved session sate)
As with calf-fluidsynth, this is probably related with inability to edit plugin parameters with "generic controls" (right-click -> "edit with generic controls" in ardour)
In yoshimi, in generic contols there is only a single switch availabe, named "freewheel". If i click on that - Ardour get properly notified that something was changed.
Hmm. I don't think so. When using generic controls the host is instructing the plugin, so would already know it had changed something.
This is now being looked at, but we won't be able to implement it for the next release which will be 28/29 Feb.
There is a new LV2 StateChanged atom specifically for exactly this scenario. One of Yoshimi's little helpers is trying to get this implimented within Yoshimi. The atom was proposed by someone fairly involved with Ardour so hopefully, this should work.
This is now completely resolved in Yoshimi's current master for the latest builds of both Ardour and qtractor. It is also in Muse staging so will be availalbe there soon too.
I'll leave it open for a while in case anyone else is watching.