

Arguably mapping out cities to this degree across the globe is a ginormous effort, on an order of magnitude more so than what Google Maps etc. currently provide. Thus I don’t think it’s entirely unreasonable to try designing something that operates purely in terms of sensory input (and of course map data where available, those approaches don’t have to be mutually exclusive).
I wonder why a permission-based approach wouldn’t be feasible. Most websites don’t need GPU access anyway, so why couldn’t a game or simulation just prompt the user quickly for granting access to the GPU?