Input lag in emulation...why?

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evil_ash_xero
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Input lag in emulation...why?

Post by evil_ash_xero »

Input lag is of the Devil.

What causes it in emulation? I mean, as far as I can tell, basically everything that is emulated, has at least a frame(if you're lucky) of input lag. What's the deal with this? Can technology not overcome lag in 20 year old games?
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StarCreator
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Re: Input lag in emulation...why?

Post by StarCreator »

Firstly, you're vastly, vastly underestimating the difficulty of an accurate emulation - try reading this article that discusses what is actually necessary to emulate the SNES accurately.

As for the original question... I'm no expert, a lot of emulators seem to work by essentially running the entire machine for a single frame, pausing the emulation, reading the inputs on the host layer, then resuming the emulation with those inputs having been passed. Would love to get some confirmation that this is actually the case.
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nZero
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Re: Input lag in emulation...why?

Post by nZero »

This topic has been done and done again, there's plenty of technical info in the various Shmupmame threads (including splitting lag created by the emulation layer and input/output lag added by the peripherals and displays used with the host system) and I'm locking this one to prevent a redux of this thread by the same author that was already covering basically the same subject matter.
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