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Comment by cyanregiment | Hacker News Reader

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cyanregiment·

I remember the infamous 300ms delay on tap when smartphones first came out.

It matters!

There is some number of fps where "the human eye can't tell the difference" I bet there is one for ms delays

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Yeah, there's actually been a lot of research on that. 100ms is generally considered to be the threshold between perceiving a delay or not. But even that needs some additional context. That's the threshold for feeling like you're waiting to get a response after completing an input. But a 100ms round-trip delay on a mouse cursor would feel like you were using a broken computer. And when you're doing something where you're used to continuous feedback from your input, you can sense incredibly small changes in the response time. +/- 10ms from what you're familiar with is noticeable for almost everyone. There are people who consistently notice half of that - but remember that's in the context of difference in latency of continuous feedback. 100ms is a pretty good rule of thumb for the threshold of "why am I waiting for this?"

100 ms might be a good threshold for a lot of purposes, but for when refresh, 30 fps is painful to use compared to 60 fps: it is extremely noticeable when moving windows, but I'm old and can tell the difference even just moving the cursor. (Others will say the same about 60 fps compared to 120 or 144 fps.)

One of the reason they gave CSS access to the GPU I guess - it would be so choppy without it

Switching from 52mm skate wheels to 54mm feels like going from a car to lifted truck - I guess the same effect.

When we learn something well we model it thoroughly and notice the tiniest change

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