LV2 on or off ?

With LADSPA effects you know they’re bypassed if they have parentheses around them in the channel strip and you can de/activate them either by clicking the Bypass button in the effect or middle-clicking it on the strip.
With LV2 there seems to be no correlation between the two ways, meaning they need to be activated both on the strip and in the effect.
Is this a bug in Ardour, something the LV2 specs can’t handle or lazy LV2-effects programmers?

One of the problems I’ve been having with LV2, I would like to be able to tie all this together but there are some things not quite working which I think are in Ardour’s implementation. E.g. When I Activate or Deactivate a plugin, the activate / deactivate callbacks in my effect don’t seem to be called so the plugin has no knowledge of what happened. These only seem to get called when then effect is deleted - when it goes something like


If these callbacks were actioned I could then tell the DSP code to bypass or un-bypass, but getting the GUI Bypass switch to reflect this appears troublesome at the moment due to the DSP / GUI communication mechanism in LV2 externalUI. I guess this will evolve, it seems to be quite a new thing at the moment.

@linuxdsp: from a quick review of the code, this is a “defect” in the 2.X code base in ardour. It has been rectified in 3.0. I will consider “back porting” this to 2.X. Thanks for bring it my attention.


If one vote means anything I would love to see anything to smooth out LV2 in the 2.X series be backported. I’d guess that users who don’t use MIDI will probably not jump at 3.0 until it is out for a while and stable and in the meantime a lot could be accomplished with the externalUI code to facilitate LV2 for current users.