Language workbenches have been segregated into those supporting textual languages and those supporting visual languages. The projectional editor based MPS has been making some first steps in combining text-like projections and more graphical projections. In the Spoofax project we have stayed away from visual languages. (There is plenty to do in supporting design of textual languages well.) Until this year.
In the Spring of 2012 TU Delft student Oskar van Rest started his Master's thesis project at the University of Queensland (Australia). He has been working on the integration of visual languages in the Spoofax Language Workbench. As case study of the integration he constructed ComBE:
ComBE provides an integrated textual and graphical editor for Behavior Engineering. It synchronises text and graphics in real-time and allows you to switch between editors at any moment in time.
He recently presented a poster about the project and created a screencast showing off the side-by-side editing of text and diagram.
Update 24/3/2013: paper Robust Real-Time Synchronization between Textual and Graphical Editors to appear in ICMT 2013