transition sunglasses are also called photochromic sunglasses. They can adjust to colored lenses when exposed to sun. The lenses within a pair of transition glasses will be clear when worn indoors and quickly become darker when outdoors to shade and filter out ultraviolet rays. But most driver thought that the transition lenses in car are not work as well as in sun. Besides, Usually, the lenses need minutes to adjust the lenses when you in sunshine or in somewhere dark light places. That cause inconvenient if you need long drive. So, if you often drive, you'd better buy a pair of wraparound sunglasses to shield your eyes when driving.
transition glasses can change the color only when they are exposed to the UV rays directly. While little rays will pass through the windshield of the car, so transition eyeglasses won't turn as dark as sunglasses. In this case, they may not block the strong light effectively. So transition sunglasses are not a good choice for driving. If you want glasses for daytime driving, sunglasses can meet your needs.