How low latency can we get?

Once we have a cheap projector to play with, I'd like to see how far down we can push the latency. It'd be nice to have near 60fps tracking but I'm not sure it's possible without custom hardware.

No file, test, or entry point is named. Start by locating the projector and tracking implementation, then measure its current latency and identify the constraints affecting frame rate. Done would require a defined latency target, reproducible measurements, and an agreed implementation or hardware direction.

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