Physically Plausible Glass

I found a post online that presented a way to create a physically plausible glass shader that had been converted from vex to c++, and after some editing and tweaking to speed up the execution as some variables were either wrong, or simply not needed and just causing overhead.  here are the results using the cook Torrance spec against a normal spec call.

Next will be to achieve colored shadows, and then i have all of the components needed for physically plausible marbles