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Keyboard latency

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Re: Keyboard latency

#221

Post by jacobolus »

abakker wrote: post #194
rcthompson wrote: post #191

Earlier quoted context omitted.

I don't think it's a matter of achieving a faster reaction time by bypassing higher brain functions. It's about looking several steps ahead and planning out multiple steps before you need to do them, and then anticipating when each action needs to happen. One game that really demonstrated this to me was Crypt of the Necrodancer. It's a rougelike where each turn is the beat of a song, and the tempo of the song for eac…

This sounds kind of like how stenographers’ keyboards work. You plan and type words with key combos. Much faster than typing since you react to whole words and think in phrases (so I was told).

Hm, not exactly. Steno keyboards work by chording. The parent poster is talking about several precisely choreographed sequential actions, more like typing on a standard keyboard/typewriter but with precise rhythm.

Re: Keyboard latency

#222

Post by lloeki »

pdkl95 wrote: post #145
BoppreH wrote: post #117

Earlier quoted context omitted.

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…

A big difference between Hexagon and most other rhythm games like Stepmania, Beatmanias IIDX, Guitar Hero, etc , is that pattern is the same. Just like musicians memorize complex music that they later perform[1] with precise timing, the same is possible for these step/note patterns. I've personally seen someone perform one of the insane speed/note-density DDR songs blindfolded . Humans have surprisingly good internal…

> I've personally seen someone perform one of the insane speed/note-density DDR songs blindfolded

Rock Band 4 has a "Brutal" mode where notes are almost completely hidden save for a slice of a millisecond at the top, but although it does give a hint of an information that may be processed in the end it mostly doesn't matter, since at that point you can effectively do it blindfolded, which is as a process no different to learning to play the actual song.

https://www.youtube.com/watch?v=xWjWnXAtvK4

Re: Keyboard latency

#223

Post by mxstbr »

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Re: Keyboard latency

#224

Post by wvh »

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…

As a guitar player, a lot of playing is muscle memory, combined with an overarching understanding of what you are trying to convey. In fact, the challenge is often to break free from the muscle memory so as not to fall into the same patterns (like minor pentatonic scale) over and over.

Part of practice is learning how to use muscle memory to handle the fast stuff – faster than you can process at full speed – freeing up your mind to think about the broader strokes. It's interesting to think that activities such as playing music, drawing, painting or practising sports are really a combination or interaction of fast muscle memory, slower rational/strategic thinking, and guiding emotion/intuition.

Re: Keyboard latency

#225

Post by ionised »

bitwize wrote: post #85
bhj wrote: post #37

Earlier quoted context omitted.

Agreed, and I don't understand the hate many people (seem to) have for them - the most ergonomic keyboards are those that require the least amount of repetitive motion. Not that there isn't an adjustment period, but some seem to pull out their Jump To Conclusion mats a little early.

If you can't adjust to an Apple keyboard (and don't have RSI), the problem is you -- not the keyboard. Retrain yourself to type softly.

Why?

Re: Keyboard latency

#226

Post by dom0 »

jetpacktuxedo wrote: post #77
dom0 wrote: post #58

Earlier quoted context omitted.

Seasoned gamers preload keys they are anticipating to use. On my keyboard I have less than a millimeter of travel from the preloaded point I use (which is right in front of the tactile bump and is quickly trained) to actuation. In tacticale switches the bump and the making of the contact are mechanically connected. Using the moment of finger/key contact quite obviously selects for travel, among other things.

>In tacticale switches the bump and the making of the contact are mechanically connected. Nope! This is rarely (if ever?) the case. In alps switches, for example, there are two totally separate leafs, one of which handles the tactile feeling and the other of which is responsible for the actual actuation. If you browse through Haata's Plotly[1] you can see that many switches actuate well after the tactile bump. Though…

> Nope! This is rarely (if ever?) the case.

Cherry MX.

Re: Keyboard latency

#228

Post by akvadrako »

rubatuga wrote: post #165

I've done a simple test with my Macbook Air, using the app "Is It Snappy", as mentioned in the comments. I used the keyboard on my macbook, which is a chiclet style mechanism. The tests were all done in triplicate except for TextEdit, (only twice) TextEdit: ~81 ms from key depression to when LCD pixels begin to shift. For Sublime Text: ~86 ms. Both of these text editors are pretty well matched. However, if you boot i…

It actually does seem a little faster, which is sad. I would like to see how much normal userspace can be optimised, and where the delay occurs:

1. between the keyboard and CPU 2. in the input subsystem 3. in the app / system libraries 4. in the display subsystem 5. between the CPU and the screen

Re: Keyboard latency

#229

Post by kwijibob »

ChuckMcM wrote: post #65

I find my typing accuracy is affected by keyboard latency. An interesting way to test this would be to use a sensor to note how the point where a key was definitely "headed down" (say > 10% of its total travel) and then waiting for the message to show up. In older keyboards the main CPU was doing some of the debouncing so it knew "right away" that a keyboard was pressed. That cuts down on latency as well. Another tes…

I am a fairly good typist (70WPM+) and I agree with this.

When I bought my first chromebook, I opened google docs and found the typing latency terrible. It couldn't keep up with me.

Then I let the chrome OS update, and everything was as smooth as butter.

Re: Keyboard latency

#230

Post by pygy_ »

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…

I mostly agree with you except for this bit:

> Not to mention that 100 ms is musically a 16th note at 150 bpm. Being off by a 16th note even at that speed is – especially for percussive instruments – obvious.

The auditory system is especially good at processing serial data, and it has a better timing resolution than the visual one.

People with visual-auditory synesthesia are much better at tracking patterns in flashes of light for example (because the hear the flashes).

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