[LV2] Updating the controls of generic user interface

[Florian Bihler]

> Plugins must *not* update their own input control ports, those are read-only.
> 
> That's why you don't see any change. Hosts don't check for changed input values,
> as plugins are not allowed to change them :)

Thanks a lot for your answer. Good to know I went the wrong direction :).

> P.s. read-write controls are possible with lv2:Parameter [1] and the patch
> extension [2], but not many hosts support them.

Do you know if there is some example code for this? Couldn't manage this based on the 
documentation.

Best regards,
Florian