The photosensitive pigments in transitions lenses react to the uv in sunlight. In cold temperatures, they will get very dark on sunny days. Most of the time the pigments are imbedded in the lens material, but a company called Beloptix has been coating the front of their lenses with a photochromic coating. Im not sure anything would be available much larger that 82mm. Maybe theres a non optical manufacturer utilizing the same idea for window panes??

Sean