Meh!
Just print qr codes on any clothing you like, different ones for every body part, shape a smartphone into a gun and make the trigger take a pic and run a qr scanner on it, if it recognizes any qr code it registers a hit to that body part.
Or send all of that data to a local server to deal with it faster than the smartphones would.
Change qr codes into distinct geometrical shapes if qr codes are too difficult to pick up on a smartphone cam.
It won't be "lazer" anymore but then again when was IR ever lazer.