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Comment by JohnBooty | Hacker News Reader

I suspect (worry?) that a lot of folks miss out on the other thrill of physical CRTs... an experience that is as close to zero latency as is physically possible.

This article breaks it down in wonderful detail: http://renderingpipeline.com/2013/09/measuring-input-latency...

The TL;DR is that on a "modern" stack (USB, display buffering, etc) with a 60hz display you're looking at over 100ms of input latency. You can roughly halve that with a 120hz display.

But it won't ever touch the sub-16ms latency that's possible with a "retro" 8/16-bit console hooked up to a CRT display.

A lot of those games were garbage, but damn... it felt like your brain was wired directly into the machine. A very very cool part of the experience that is being lost to time.

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Yes, the same thing with telephone calls over copper. No latency. You could both talk at the same time, more immersive.

I also remember vector displays first-hand.. those were pretty awesome. You're never going to get a vector graphics experience ever on an LCD because LCDs are rasterized pixels not a drawn line.

No one will ever make a limited run of CRTs or vector monitors ever again, but I wish they would. People would buy them.

I can't find the link now but there is a company making still brand new CRTs and the owner has considered making some for gamers, however i doubt this will be a thing since - at least for now - CRTs are easy to find for very cheap and a limited run would be very expensive. Exception being the high end trinitrons and similar, but i doubt said company is making CRTs of that caliber (i think they're making TV-like stuff) anyway.

Perhaps in 20 years if they're still around things will be different though. After all CRTs do wear out from use.

I have an old Vectrex video game that I got as they were closing them out. Amazing machines because they had the monitor built in, you didn't have to connect them to a TV. Because the monitor was built in they could drive it any way they wanted, so it was vector all the way - no rasters.

That's a great example. Nobody will ever really experience that again!

   No one will ever make a limited run of 
   CRTs or vector monitors ever again, but 
   I wish they would. People would buy them.

The prices people are paying for high-quality CRTs today are proof of that. I was lucky enough to get a sweet Sony PVM before the prices really went through the roof.

But yeah, they'll never be manufactured again. It would be such an absolutely massive undertaking.

   I also remember vector displays first-hand.. those 
   were pretty awesome. You're never going to get a 
   vector graphics experience ever on an LCD because 
   LCDs are rasterized pixels not a drawn line.

Yeah and there's also the temporal aspect -- the "smearing" of ultrabright vector dots, like your bullets in Asteroids.

I've seen folks be totally blown away when seeing something like an Asteroids cabinet in person for the first time.

Resolution is rapidly reaching the point where it won’t be the limiting factor in properly simulating a vector display, at least in a “good enough” fashion. Similar to how resolution and refresh rate improvements are making it feasible to simulate a raster CRT.

At this point, one of the primary limiting factors is the reality that the majority of folks using and implementing emulation technology probably have never seen a vector display in the flesh.

Conceptually, emulating a vector display is easy. They are unique but not thaaaat magical.

1. You have a certain amount of bloom

2. You have decay time function

3. You need, perhaps, a surprising amount of dynamic range? If you've seen something like an Asteroids cab in person, the bullets are super bright (with correspondingly larger decay times) relative to everything else

But, how people are interested in implementing that kind of thing and have access to a real vector display in order to study it? I suppose sufficiently good recordings of vector displays might suffice so maybe it's not that dire.

Sub-16 ms latency is still possible with modern hardware and 60 Hz AMOLED/LCD displays. It's probably not quite as low as an ideal CRT setup, but it should be pretty close. Most modern latency comes from the software stack, so I don't think switching monitors will make that big of a difference.

Example of 10 ms latency on a phone with an OLED display: https://twitter.com/kdrag0n/status/1291213993219039232 (source code: https://github.com/kdrag0n/touchpaint)

Drawing on the screen almost feels natural with such low latency, and it's probably ine of the most latency-sensitive applications for modern computers.

Impressive work! Makes sense that this would require writing directly to the framebuffer - that was the oldschool way after all, and it's pretty cool to see this done on a modern device.

You can get 37.5ms latency on a MacBook Air running at 60Hz: https://news.ycombinator.com/item?id=15488191

I think if you use a 120Hz monitor on a Linux text console, it would be sub 20ms.

That's awesome!

I love that one reply:

    "This is incredible. Single user mode 
    feels like the screen updates BEFORE 
    pressed the keys, like it is time 
    travelling. I guess I've used to the 
    high latency on newer computers."

Do you know of any games/emulators that run in such an environment? (Maybe stuff like RetroPie does by default, I have no idea!)

Closest I can recommend is FreeDOS to run games natively. It's so good but the drivers are very basic. It does have a package manager.

This is part of why I’d be happy to see more hardware reproductions of classic computers and consoles. Emulators are pretty good but they bring a certain amount of unavoidable overhead that can never be entirely eliminated.

psychophysicists love them for exactly this reason. it's easier to put an accurate physical timestamp on the display of a stimulus with analog crts without resorting to measuring an onscreen fiducial marker.

Yes - that's a great point. Although from the article, it seems that most of the latency isn't down to the display, but to the CPU/GPU part of the chain?

Yes, about 2/3 of it comes from the software/hardware stack in your computer/console.

The remainder (a few frames' worth of latency) is from the display itself. There's something like a frame buffer inside the display if I understand correctly although implementations vary widely; some displays are good for gaming and some aren't.

If you have a chance to game with original 8/16-bit hardware with wired controllers on a real CRT it's such a treat. You can really feel the difference.

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