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Keyboard latency

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Re: Keyboard latency

#121

Post by LaikaF »

BoppreH wrote: post #117
pdkl95 wrote: post #92

Earlier quoted context omitted.

> strike a key less than 100 ms after some visual stimuli, I'm sure I couldn't do it The video game "Super Hexagon"[1] is a surprisingly interesting demonstration of this limitation, and how the mind tries to workaround the problem. The higher difficulties ("hexagonest"[2]) seem impossible at first. In the easier levels you can react , but now the time it takes to see the scree, parse the simple graphics, recognize t…

This is also clear on rhythm games like Stepmania. Here's a random video from a keyboard user: https://youtu.be/TWiMnENdcyY?t=56 At this speed the player is reacting (and hitting with correct timing) about ten notes (arrows) per second. This is possible by memorizing and reacting to group patterns instead of individual notes, but more importantly, reacting unconsciously. A player can play at this level without consci…

When I used to play Stepmania and DDR a bunch that was entirely what ended up happening. You started processing chunks of the arrows, and mapping them to various foot/finger movements. At a certain point though people just straight up memorize the whole song though.

Re: Keyboard latency

#122

Post by dlubarov »

a_t48 wrote: post #51
dsr_ wrote: post #15

Earlier quoted context omitted.

Yes, they want freesync or g-sync monitors with high refresh rates.

Or a good enough machine so that you never dip below native framerate.

That's tangential though. Whether or not you have skipped frames, G-Sync/FreeSync tend to reduce input lag, because the panel's refresh events will be timed such that they're closer, on average, to the times when new frames become available.

Re: Keyboard latency

#123

Post by kllrnohj »

matthavener wrote: post #3

PS/2 keyboards are used by serious gamers because the scan rate is higher than USB. See https://superuser.com/questions/16893/do-usb-or-ps-2-keyboar...

I'm unaware of any pro gamer (or streamer) that's using PS/2, and that's about as serious a gamer as you get. Most are using a late model mechanical keyboard connected via USB, often with lots of RGB just because.

I think the only PS/2 holdouts you'll find are the old Korean Starcraft players that are still using a Qsenn DT-35.

Re: Keyboard latency

#124

Post by madez »

BoppreH wrote: post #117
pdkl95 wrote: post #92

Earlier quoted context omitted.

> strike a key less than 100 ms after some visual stimuli, I'm sure I couldn't do it The video game "Super Hexagon"[1] is a surprisingly interesting demonstration of this limitation, and how the mind tries to workaround the problem. The higher difficulties ("hexagonest"[2]) seem impossible at first. In the easier levels you can react , but now the time it takes to see the scree, parse the simple graphics, recognize t…

This is also clear on rhythm games like Stepmania. Here's a random video from a keyboard user: https://youtu.be/TWiMnENdcyY?t=56 At this speed the player is reacting (and hitting with correct timing) about ten notes (arrows) per second. This is possible by memorizing and reacting to group patterns instead of individual notes, but more importantly, reacting unconsciously. A player can play at this level without consci…

I still remember vividly the learning process when playing a game like Stepmania (maybe it actually was Stepmania, I don't remember the name).

The first season was played very conciously and slow. After each season, I recognized that certain patterns just came out perfectly without difficulty. Sometimes I was even surprised by myself.

However, what I wanted to say is, it was enjoyable just letting the brain do its job of processing patterns and reacting to them. It was relaxing.

Re: Keyboard latency

#125

Post by greggman »

I'm confused. the first claim is Apple 2 has a fast response The second claim is that key travel matters. Short = faster

But Apple 2 keys are not short travel keys

Re: Keyboard latency

#126

Post by organsnyder »

BoppreH wrote: post #117
pdkl95 wrote: post #92

Earlier quoted context omitted.

> strike a key less than 100 ms after some visual stimuli, I'm sure I couldn't do it The video game "Super Hexagon"[1] is a surprisingly interesting demonstration of this limitation, and how the mind tries to workaround the problem. The higher difficulties ("hexagonest"[2]) seem impossible at first. In the easier levels you can react , but now the time it takes to see the scree, parse the simple graphics, recognize t…

This is also clear on rhythm games like Stepmania. Here's a random video from a keyboard user: https://youtu.be/TWiMnENdcyY?t=56 At this speed the player is reacting (and hitting with correct timing) about ten notes (arrows) per second. This is possible by memorizing and reacting to group patterns instead of individual notes, but more importantly, reacting unconsciously. A player can play at this level without consci…

I used to play Stepmania a fair amount, and one of my controllers had a noticeable amount of latency. Despite this, I was about to be about as effective as with the lesser-delay controllers.

I think part of the reason is from my experience as an organist: some instruments have a noticeable delay from the time that the key is pressed to when the sound reaches my ears, whether due to delays built into the control mechanism itself, as well as sound delay (the console is sometimes located on the opposite side of the hall from the pipes). I think this has caused my brain to be wired to accommodate these sorts of situations.

Re: Keyboard latency

#127

Post by tammer »

colanderman wrote: post #9

I'm surprised the "humans don't notice 100 ms" argument is even made. That's trivially debunkable with a simple blind A/B test at the command line using `sleep 0.1` with and without `sleep` aliased to `true`. To my eyes, the delay is obvious at 100 ms, noticeable at 50 ms, barely perceptible at 20 ms, and unnoticeable at 10 ms. Not to mention that 100 ms is musically a 16th note at 150 bpm. Being off by a 16th note e…

For more on this I highly recommend Jimena Canales' "A Tenth of a Second: A History"[1]

  [1]: http://www.press.uchicago.edu/Misc/Chicago/093185.html

Re: Keyboard latency

#128

Post by comex »

ryandrake wrote: post #116
andyfleming wrote: post #24

Earlier quoted context omitted.

That's fine though. It's about the experience end-to-end. I love the apple keyboards. I still type faster on them than other keyboards, including high-end mechanical keyboards. The short keys and actuation feel responsive, yet I've never felt like I've accidentally triggered a key.

That's fine, but then the study should be called Key Size Comparisons rather than Keyboard Latency, since it appears that the length of time the key takes to travel dominates the "latency" measurement.

Key travel time is itself a form of latency, distinct from throughput because it doesn’t count the time you take to move your fingers between keys, because you can start pressing a one key while the previous key is on the way down (as long as it’s not the same key), etc. But even aside from that, if key travel time is the biggest contributor to a keyboard’s overall input latency, then that’s what it is. There’s no real way to avoid it (except maybe pressing the keys harder?), so it doesn’t make sense to exclude it just because it’s mechanical rather than electronic.

Re: Keyboard latency

#129

Post by stevelosh »

xigency wrote: post #32
Stenzel wrote: post #29

Compare with musical keyboards where not only key number but also the velocity matters, so each key has two electrical contacts, and the whole thing is usually scanned around 10kHz for proper velocity measurement. Although key contacts are arranged in a diode matrix, the latency is usually below 2 ms, even with good old MIDI. So neither the keyboard matrix nor the debouncing justify a latency of 10 ms or above. It is…

Now to learn to type with a keyboard... or game I suppose.

Have fun: http://joon.be/portfolio/canabalt-100/

Re: Keyboard latency

#130

Post by skeleton »

pdkl95 wrote: post #92
colanderman wrote: post #9

I'm surprised the "humans don't notice 100 ms" argument is even made. That's trivially debunkable with a simple blind A/B test at the command line using `sleep 0.1` with and without `sleep` aliased to `true`. To my eyes, the delay is obvious at 100 ms, noticeable at 50 ms, barely perceptible at 20 ms, and unnoticeable at 10 ms. Not to mention that 100 ms is musically a 16th note at 150 bpm. Being off by a 16th note e…

> strike a key less than 100 ms after some visual stimuli, I'm sure I couldn't do it The video game "Super Hexagon"[1] is a surprisingly interesting demonstration of this limitation, and how the mind tries to workaround the problem. The higher difficulties ("hexagonest"[2]) seem impossible at first. In the easier levels you can react , but now the time it takes to see the scree, parse the simple graphics, recognize t…

I finished that game a few years ago (was most definitely worth the 60 cents I paid for it).

From what I recall, to finish the final level I was relying for the most part on 'muscle memory' in relation to the familiar patterns. I would visually interpret what kind of pattern it was, my position relative to the pattern and then there seemed to be a conscious disconnect to the actions I performed to get through the pattern.

I think it's interesting because the actions I'm referring to weren't merely a sequence of button presses performed as fast as you could. There was a critical factor of very small differences in durations between actions and how long you execute actions for that seem (and I assume are) completely beyond my conscious abilities.

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