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A Silly Usecase for WebSockets (strobe warning)

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Re: A Silly Usecase for WebSockets (strobe warning)

#61

Post by Retr0id »

lysium wrote: post #31
Retr0id wrote: post #29

PSA: Viewing strobing images has caused temporary (lasting hours) backlight issues on my 2021 Macbook Pro, in the past. Somehow, it causes the backlight to continue flickering for some time afterwards, even when looking at static images. It is barely perceptible, but quite noticeable at the edges of the screen - enough to be annoying. I have no idea if this is a hardware issue with my specific unit, or a more widespr…

Are you sure it's your backlight and not your eyes? (Something like this: https://en.wikipedia.org/wiki/Motion_aftereffect )

I caught the flickering on camera (see my other reply). Furthermore setting the display to 60fps (as opposed to 120Hz "ProMotion" VRR) made the flickering go away, and it would come back when I switched back to 120Hz.

Re: A Silly Usecase for WebSockets (strobe warning)

#63

Post by Kalabint »

Orangeair wrote: post #62

Seems to have been killed, there's just question marks everywhere there should be a dynamic value, and I can't interact with anything (Chrome for Android). > ? in the room, click anywhere to turn the light ? > click counter: ?

It's still running, with currently 393 Users and a total of 250000 Clicks. The organic User average seems to be around 50, so i think someone is trying to stress test the System.

Re: A Silly Usecase for WebSockets (strobe warning)

#65

Post by lewispollard »

Retr0id wrote: post #61
lysium wrote: post #31

Earlier quoted context omitted.

Are you sure it's your backlight and not your eyes? (Something like this: https://en.wikipedia.org/wiki/Motion_aftereffect )

I caught the flickering on camera (see my other reply). Furthermore setting the display to 60fps (as opposed to 120Hz "ProMotion" VRR) made the flickering go away, and it would come back when I switched back to 120Hz.

I've seen this on my phone's 120hz display too (S21 Ultra) and haven't yet determined the cause, but maybe it is related to strobing content. Will have to remember that the next time I notice it.

Re: A Silly Usecase for WebSockets (strobe warning)

#66

Post by dang »

noduerme wrote: post #44

Quoted post unavailable.

You've been breaking the site guidelines repeatedly lately. We ban accounts that do that. If you'd please review https://news.ycombinator.com/newsguidelines.html and stick to the rules when posting here, we'd appreciate it. We've already had to ask you about this before.

Re: A Silly Usecase for WebSockets (strobe warning)

#67

Post by ASalazarMX »

JKCalhoun wrote: post #57
quintussss wrote: post #6

Earlier quoted context omitted.

Yes absolutely, this was not an issue when it was just me and some friends using it.

Threw together a couple PNG files. They look good against a 50% gray background. Perhaps a lighter gray for light_on, a darker gray light_off. Not as hard on the eyes. https://imgur.com/m2uznrc https://imgur.com/wSphM0b

I much prefer the original eye-watering version. The friendly colors stray from the spirit of an annoying prank.

Re: A Silly Usecase for WebSockets (strobe warning)

#68

Post by ASalazarMX »

sodimel wrote: post #24
cududa wrote: post #15

I appreciate the strobe warning! Not gonna open it so I have no idea what it is but congrats on whatever it is. Anyway have an up vote for the strobe warning

Here's a (static, that don't flash) screenshot: https://up.l3m.in/file/1645698692.png edit: and here's a (very slow, 2s transition) gif of what it renders to: https://up.l3m.in/file/1645698812-slow-strobe.gif

Curiosity is such a wonderful trait.

Re: A Silly Usecase for WebSockets (strobe warning)

#69

Post by gruez »

Retr0id wrote: post #61
lysium wrote: post #31

Earlier quoted context omitted.

Are you sure it's your backlight and not your eyes? (Something like this: https://en.wikipedia.org/wiki/Motion_aftereffect )

I caught the flickering on camera (see my other reply). Furthermore setting the display to 60fps (as opposed to 120Hz "ProMotion" VRR) made the flickering go away, and it would come back when I switched back to 120Hz.

That still might be to your eyes. The relevant effects are:

1. effects from your eyes (from looking at the strobing image)

2. PWM brightness controls causing your recordings to look like they strobe

The site in the OP wasn't working, so I tried a demo site instead: https://www.da.vidbuchanan.co.uk/strobegate.html. I looked at the strobing image, closed the tab, and sure enough my monitor (IPS, 60hz) was showing some signs of flickering. It disappeared after a few minutes. However, I performed a second test where I opened the site and didn't look at it with my eyes. The strobe after effect did not show up. Even though I didn't look at the monitor, I verified afterwards that a strobe was shown by a phone video recording. I also did a slo-mo video recording of my monitor without any visible strobe effect, and there was visible strobing in the recording, probably from the shitty PWM. You should follow a similar procedure to rule out whether it's something with your eyes or not.

Re: A Silly Usecase for WebSockets (strobe warning)

#70

Post by heleninboodler »

bandamo wrote: post #32
niel wrote: post #10

EPILEPSY WARNING. Extreme strobe upon opening OP link. while (true) { websocket.send(JSON.stringify({ action: 'plus' })); } Really messed with my vision and crashed chrome. Fun experiment!

no crash with: setInterval(() => { websocket.send(JSON.stringify({ action: 'plus' })); }, 0)

  setInterval( () => { if(state.textContent == 'on') {
    websocket.send(JSON.stringify({ action: 'plus' })); } }, 50)
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