My memory is a little rusty on this, but I think Doom's "multi-monitor" was actually multi-computer.
One machine was the host (and the center display), and other machines would be started with "doom -left"etc, and some network info, and they would get the info they needed to render over the network.
One machine was the host (and the center display), and other machines would be started with "doom -left"etc, and some network info, and they would get the info they needed to render over the network.
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