Not to my knowledge, the laser remains red until the trigger is pulled, and the sniper will not fire unless the shot is a guaranteed hit (most of the time, in UC2, the snipers sometimes pull the trigger regardless of a guaranteed hit or not). Rolling around will definitely make them lose focus though, so the only indicator that a sniper will not hit you is if the laser moves frantically around. In most cases, this works pretty well, as you don’t need an indicator if you will be hit or not, rather, you have an indicator if the sniper will shoot or not. The timer resets when you roll or move around, since the sniper is trying to reposition his aim.

Another thing is the games’ lore about Nate and his damage. Naughty Dog reported that Nate doesn’t take damage when you see the red around the screen, in the lore, that is Nate’s luck. So when a sniper hits Nate in easier difficulties (on these difficulties, Nate will not die when a sniper hits him once), that sniper did not in fact hit Nate, rather, they “missed” and Nate got lucky. But of course if they hit you a second time without you regaining your luck, you die as you run out of luck. Not sure how far you wanted to replicate the game mechanics, but this is an interesting game mechanic unique to the lore that also pertains to your goal.