from my point of view this should be a very basic question, but I could not find any satisfying answer by myself. So, I hope you help me out
I'm going to develop an analysis plugin, which should display additional information in an existing Graphiti-Editor. Therefore it would be great, if these information are just displayed and not stored in the underlying EMF-Model. If I want to edit for example a PictogramElement, I'll get following Exception: "Cannot modify resource set without a write transaction". Is it possible to modify a graphical element without changing the underlying emf model?
It would be great, if you provide some sample code.
Not sure about this, but my guess is, it's not. Graphiti uses the graphical elements to decide what to display and what happens when you click at some place. These elements are in the EMF model with all the links, etc.
Perhaps an alternative is to have a new EMF model, or (more complicated) have a layered model in some way?
Several posts here are about having a custom file format, you could perhaps consider your problem to be such a case as well.