Consider the Flash, with the speed and reaction time to pluck bullets out of the air.
That wouldn’t keep you from getting shot in the back of the head with a supersonic round with no warning to react to. He could constantly look around, swiveling his head at thousands of RPM to look everywhere, which would be an interesting visual effect, but another option would be to compress a 360 degree visual field into the straight ahead view.
There have been novelty “see behind you glasses” forever, but AFAIK, there haven’t been any attempts at giving full 360 degree vision.
There have been experiments where psychologists put mirror glasses that flipped the visual field on people to test the adaptability of the brain’s visual system, and it was found that the view change was initially incapacitating, but over the course of a couple weeks, people could adapt to it. Taking them off then took a couple weeks to fully retrain for normal vision.
For the Flash, it couldn’t be a camera-and-screen pass-through VR system, because you would need thousands of frames per second to accurately estimate the trajectory of a bullet, but a purely reflective system of curved mirrors could do it.
A non-linear warping would be harder to adapt to than a simple mirroring, because different eye positions would have different distortions. For conventional human reaction speeds, pass-through VR systems with eye tracking could compress everything into the peripheral vision and leave the fovea untouched, which would probably speed adaptation significantly.
I can imagine special forces teams having to wear their 360 vision helmets for a couple days prior to a mission, akin to deep sea divers having an extended prebreath and decompression phase.
@PalmerLuckey
The comic-friendly fix is to just assume that the Speed Force gives the Flash an awareness of anything moving fast in his vicinity, although another thought I had is that while the speed of sound in air is only 330 m/s, the speed of sound in the ground is almost 10x that, so you might be able to “hear a gunshot” with your feet well before you could with your ears.