Hi,
I got the problem previously with some production with MentalRay or scanline renderer in Max, and now i got the same need with Corona, and i think this engine is more powerfull and active to get a way to generate this render pass.
The idea is to get a mask of object(s), like "CMasking_Mask", but with the result of refraction generate in/or behind a glass object.
Please see attach images to clarify need, this kind of pass can be really usefull to modify object(s) or material color / highlight / or any other action at compositing.
Thanks for your help and idea and solution.
Mr