Hi @Eugenia,
I am not sure at the moment. That is another question I have: what would be the best way to connect it? I had thought about using pipes but there’s probably a better, easier, quicker way. If possible, I’d rather not use pipes. 
O.k. I know about client-server, but I am not sure how that would work in this instance. Could you please explain how that might work with the plugin API? 
I thought I would give some background as well, as that might help you to know what I am planning:
The workflow I am picturing would be something like:
- The user selects an image in the Lunacy document.
- The user brings up the context menu and clicks the option to launch the bridged image-editing application.
- The application is launched (as a separate process, I am thinking), with the selected image automatically loaded in the editor.
(The following is stuff I am not 100% sure on)
- The user does their editing in the application, and as they are doing so (each time I updates?) the image in Lunacy is updated.
Thus, the user can return to Lunacy whenever they are happy with their edits or bring back up the bridged application (assuming they haven’t closed the bridged application or Lunacy) to do more editing. (When the user brings the bridged application window into focus, I would just have it update the image automatically from Lunacy)
Thanks for your time!