[LAD] Qt GUI for LV2 Plugin

[Gabriel M. Beddingfield]

On Sat, 12 Jun 2010, Jeremy wrote:

> Can you tell me where I might find some documentation on the external UI
> extension?  When I followed that link, I followed the URI in the header file
> to
>
> #define LV2_EXTERNAL_UI_URI "http://lv2plug.in/ns/extensions/ui#external"

The header is also the documentation, as is the DSSI-like 
universal "wrapper" example.

> If that is the *internal* UI extension, and seperate from the *external* UI
> extension, is there some other wiki page about the external UI extension?
>
> Also, what is the difference?  I understand the concept of an external UI,
> which is a seperate window launched by the plugin host which controls the
> plugin inputs, but I don't really understand what an internal UI would be.
> Wouldn't that just be the generic GUI generated by the host?

The difference:

How does the UI and the plugin communicate?

     Internal: Via LV2 Event messages.
     External: Via any inter-process communication system
               you can figure out... often OSC.

Who does the UI communicate with?

     Internal: The LV2 host application.
     External: The plugin via the IPC mechanism.

Who does the plugin communicate with?

     Internal: The LV2 host application.
     External: Both the LV2 host application and
               anyone connected to it's IPC channel.

Who is responsible for drawing the GUI components?

     Internal: The LV2 host application.
     External: An external process is spawned and
               is responsible for all I/O.

Hope this helps!

-gabriel