As always thanks a lot, mostly you Dan and David for your always supporting answers :D

I have a really huge problem going on. I want my software to compute thermal bridges hence I have implemented an editor in SketchUp for applying Psi-value to SketchUp Edge objects. Thanks to OpenStudio::Plugin.model_manager.model_interface.openstudio_model.getSurfaces[0].drawing_interface.entity that dear Dan showed me in here I can get edges of surfaces.

However the problem is for storing the data I can't use the SketchUp entity ID as they are temporary and change with each load (very horrible idea by SketchUp by the way...) so I have to make a key myself by hashing the position of the start and end of the edges.

The problem starts where these positions seems to be local within the groups. So my question is how do you get the global position of edges in the OpenStudio plugin itself? or do you have any suggestions.