Applied Sciences Group: High Performance Touch

I'm taking issue with latency in general and it's dismissal. There are reams of ergonomic targets, data, and guides on user interface latency that are just completely ignored these days. A terminal is close to the simplest possible interface whose job is to provide input and output to a user with as little disruption as possible. 30 ms is in fact noticeable. Here is a short video from Microsoft (about 10 years old now) on the experience of using a touchscreen with 100ms of delay vs 1ms showing the steps in between. The difference is extraordinary for the user even if the end result is the same. [this video]

From TFA: > The first important idea is that in Wayland, every > frame is regarded as "perfect." That is, the client > application draws it in a completed form [...] This is interesting, but also seems to run counter to recent work on the importance of very low latency feedback. See John Carmack's recent article on latency mitigation for VR headsets[1][2] for a very detailed example of this issue. Similar ideas also apply to touch[3][4] and even good old keyboard & mouse input schemes. There's a tradeoff between "perfect" frames and latency (see Carmack's post). From the quote, it appears that Wayland's design choice may limit achievable latencies for low-latency applications. [1] [link] [2] #1 on HN: [link] [3] [link] [4] [this video]

May be Speed isn't the right word, Latency would be better. We can look at Input Lag [1], and Microsoft Research's work [2] on Touch Input. Apple's ProMotion being part of that as well. For the past 20 years we have make 10 - 100x improvement in bandwidth at the expense of Latency. Now we need to do more work on it . Especially if we want VR or AR which are extremely latency sensitive. John Carmack [3] used to talk a lot about it when he was still working on Oculus. How it was faster sending something hundreds of miles away than showing it on your computer screen. [1] [link] [2] [this video] [3] [link]

Oh thank goodness, so it's not just me who is driven insane by the mouse lag in browser input. And while I understand your cynicism, I don't think it's deliberate as much as it's complacency, given that it's latency issues all the way down when it comes to modern user interfaces. A literal decade ago Microsoft Research uploaded a video highlighting how much of an effect minimizing latency for touchscreens had on the user experience[0]. The vast majority of tablets still utterly suck in this regard a decade later, and I wonder if any manage to get below the 10ms barrier. And of course there is Dan Luu's famous 2017 article on computer latency in general[1]. [0] [this video] [1] [link]

You can easily observe how significant latency is in videos like this: [this video] (Microsoft Research presenting its ultra low latency displays for touch interactions). Many mobile games have you drag and drop things, so it's not like it's just first person shooters that suffer from latency. You're a lay person, you couldn't have known this, you're using words with very specific meaning to streaming (like latency) and you're comparing it to human reaction times, which are measuring something else entirely. You kind of reasoned about from a first principle in a very Paulgrahamarian way, and it led you deeply astray. That happens. And you're not the only person doing this, this is a comment section full of people who play games and parrot stuff they seen in YouTube, and don't have a concrete grasp of what it is they're even talking about, so it's understandable when it's laypeople shouting at laypeople that it's just a bunch of blah. One of the reasons I hate HN and write in throwaways nowadays is that the comments section is a better example of Knoll's law than actual journalism.

> I seem to remember that a good pencil has lag on the order of 1ms (how long it takes the tip to settle out after high speed motion), but I don't remember where this number came from, so it's untrustworthy. Not sure what lag there is on actual pencil, but there's this somewhat famous video[0] from Microsoft Research, where they test various values of input lag on a touch screen, and demonstrate that even 10ms is noticeable - but 1ms is about enough for it to feel instant. With 1ms lag, drawing on a tablet seems to feel just like drawing on paper (I personally haven't had an opportunity to test a tablet with 1ms lag, so I can't tell). -- [0] - [this video]

The F1166 standard permits up to 250ms latency for touch screen response. That is ridiculously high. It practically guarantees people will think it's not working and tap again, undoing any toggle function they might have activated. They won't necessarily notice their mistake. I once accidentally ran a washing machine at 90C temperature because of high-latency touch controls. I instinctively double-pressed the touch surface to reduce temperature because I thought the first touch hadn't registered, causing it to wrap around back to maximum. It did some minor damage to the clothes before I noticed. And that was with more like 200ms latency, not 250ms. Latency on touchscreens is more important than with physical controls because there's no tactile feedback. Even 10ms is obviously imperfect for drag controls. Microsoft Research published a demonstration video: [this video]