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Bouncing DVD Logo

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Re: Bouncing DVD Logo

#251

Post by Cyykratahk »

XaspR8d wrote: post #22
pier25 wrote: post #5

I was wondering why the animation was so stuttery and then I saw they are using setInterval for the animation... Jesus it's 2020 at least use requestAnimationFrame! https://flaviocopes.com/requestanimationframe/

Or alternatively, write it as a CSS animation and modify it on collision.

Exactly. This is what CSS Animations [1] were made for. And you don't even need to do collision detection, as CSS can already alternate directions and loop infinitely.

https://bouncing-logo-css.glitch.me/

Just needed a tiny bit of JS to set the sizes and randomise the logo colour.

[1] https://developer.mozilla.org/en-US/docs/Web/CSS/CSS_Animati...

Re: Bouncing DVD Logo

#252

Post by interestica »

fidelramos wrote: post #189
z3t4 wrote: post #179

Earlier quoted context omitted.

I visited a TV shop about 5 years ago and some of the TV's up on display had the demo image burned in. So it's probably still a problem.

From what I have heard this is a problem with OLED panels.

As unread this comment on a white background on my phone (Note 8) I can see the burned-in remnants of the keyboard.

Re: Bouncing DVD Logo

#253

Post by M2Ys4U »

projektfu wrote: post #99
Arbalest wrote: post #74

Earlier quoted context omitted.

DVD was also popular around the time that Plasmas were being introduced, which also had burn in issues.

Yeah, those were mad expensive. I remember complaints about the logo "bugs" on TV stations that were fixed parts of the display.

Yeah the BBC News DOG was got burned in to our plasma TV pretty bad when I was a kid

Re: Bouncing DVD Logo

#254

Post by peterlk »

ComputerGuru wrote: post #11

In 1999, my DVD player could do this smoothly without any hitches or glitches. In 2020, my Xeon can't render this fast enough to avoid stutters. Either code quality has gone way down or my DVD player had a faster CPU.

I'm a bit surprised and saddened by how literally this comment is being taken by replies. I think it's an apt comment, so I'll explain how I see it. My takeaway of the point is that we now live in an age of excessive abstractions. This is just a fun toy, so I don't want to be too critical of this case. But in other applications, excessive abstractions allow us to ship things that don't work, but look like they do. This fills the internet and our phones with garbage.

Re: Bouncing DVD Logo

#255

Post by garaetjjte »

extrapickles wrote: post #173
aasasd wrote: post #165

Earlier quoted context omitted.

I still don't know what it is about 60 Hz that made me see the flicker plainly as a strobing light. TVs at 50 Hz—nothing (other than being generally bleh back then). Had to use 800x600 instead of 1024x768 just to have 85 Hz instead. On LCDs, I still can see faint flicker on some static backgrounds, and I think 60 Hz might play a role here too—though it seems to also depend on the brightness and Flux being on or off.…

The LCDs you see this on are 6-bit color displays using temporal dithering to pretend to be 8-bit color.

The reason for flickering on specific patterns is independent of temporal dithering. This is caused by cyclic polarity inversion: http://www.lagom.nl/lcd-test/inversion.php

(temporal dithering usually is visible as slight noise on darker shades)

Re: Bouncing DVD Logo

#256

Post by aasasd »

blattimwind wrote: post #196
aasasd wrote: post #165

Earlier quoted context omitted.

I still don't know what it is about 60 Hz that made me see the flicker plainly as a strobing light. TVs at 50 Hz—nothing (other than being generally bleh back then). Had to use 800x600 instead of 1024x768 just to have 85 Hz instead. On LCDs, I still can see faint flicker on some static backgrounds, and I think 60 Hz might play a role here too—though it seems to also depend on the brightness and Flux being on or off.…

Three reasons: You sit much closer to a computer screen compared to a TV, so your peripheral vision has a better chance with the computer screen to see flicker. Computer CRTs supported higher refresh rates, so they used phosphors with shorter afterglow (otherwise you'd get ghosting/S&H-like artifacts like TFTs produce). You can notice this one when you photograph a computer CRT vs. photographing a TV with the same sh…

Interesting hypotheses, though I still can't quite accept them as final. I seem to recall that the effect was much more noticeable, not only when sitting in front of the screen—basically enter the room and there it is. And I think that I've experimented with lower refresh rates too, at least I definitely had the time and inclination—but can't remember if the monitor allowed them with the available resolutions. It's stuck in my memory that only 60 Hz does this.

When I get rich and have lots of free time, I'll probably buy a bunch of old CRTs just to dig to the roots of this.

Re: Bouncing DVD Logo

#257

Post by [deleted] »

dawnerd wrote: post #204
ricardobeat wrote: post #143

Earlier quoted context omitted.

There are no elements in the page for style to be recalculated, so I doubt the reflow is what's slowing it down. I'm curious on what could cause bad performance for you though. It runs smoothly at 60fps on an iPhone 11 and the iPad, using Safari. Did you open the standalone page at https://wwpzj.csb.app/ ? My only guess would be that the CodeSandbox UI is too heavy for mobile. For science, I went ahead and converted…

Not smooth here either. Can tell it wants to but will hiccup every now and then.

[deleted]

Re: Bouncing DVD Logo

#258

Post by foobarbecue »

ccozan wrote: post #192
foobarbecue wrote: post #188

Earlier quoted context omitted.

Yeah, and I had 3d shutter glasses that worked great with the trinitron... In 2000 or so. Nvidia 3d Vision came along later but now sadly those product lines are abandoned, I guess due to VR which is just not what I want at all

Wow, such memories with the 3D Vision. Was quite visionary. And indeed I had to buy a Sony Trinitron with 120Hz refresh otherwise it wouldn't work. I remember playing MoH:AA, the play experience was quite out of this world.

Coincidentally, my whole team still uses Nvidia 3d Vision 2 at work, despite lack of support from Nvidia. One of the reasons I took the job is because I saw they were using it. Not having access to those systems is one of the hardships of working at home. https://www.jpl.nasa.gov/news/news.php?feature=7638&fbclid=I...

Re: Bouncing DVD Logo

#259

Post by soylentcola »

gattilorenz wrote: post #220
dredmorbius wrote: post #187

Earlier quoted context omitted.

Numerous monitors had degaussing features, Sony's among them.

And if they didn't, and somehow you managed to magnetize it, you needed to use a degaussing coil, moving it away from the screen in a spiralling motion... ah, the memories. https://www.youtube.com/watch?v=3pVLizAHby4

I assume that by "somehow managed to magnetize it" you mean "had crappy detachable boom box speakers sitting on top of it in college, causing the TV to eventually display distorted blobs at the top edge of the image".

No? Huh, guess it was just me ;)

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