It's not specifically for split screen gaming, but it specifically splits up the rendering of a screen by rows of pixels. Which seems like it's not too far off from having those be two different rendered views.I mean I guess the patent could be used in an already splitscreen game to increase framerates so I guess it's technically relevant.
PS5 1 could render the top half, PS5 2 could render the bottom half.
I'd be fine with your suggestion though of just having each PS5 do its own thing with online multiplayer, and then the tv or something combining the views.
