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Bouncing DVD Logo

bouncingdvdlogo.com

171–180 of 293 posts

Re: Bouncing DVD Logo

#171
post #115

Earlier quoted context omitted.

I still remember dragging my CRT around to LAN parties... oh the good old days... was such a pain in the ass though in reality...

Those Sony Trinitron's were literally were made of lead. My back still hurts, but the 20" was worth it!

Was that the one with the demagnitize button? I used to slap the monitor while pushing the button so my coworkers would think I hit it so hard the image bounced around

Re: Bouncing DVD Logo

#173
post #165

Earlier quoted context omitted.

I never noticed a benefit over 70 or so. The flicker of 60 made my eyes bleed though. Then with LCDs 60 was fine.

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.

Re: Bouncing DVD Logo

#174
post #60

As a historical note, the bouncing logo wasn't just for fun, but was important to prevent screen burn-in on CRTs. If you had a static image on a CRT for a long time, it could damage the phosphor. Sometimes you could even see the image when the screen was off! This was the original purpose of screensavers, which saved your screen from damage. Displaying a dynamic image prevented one part of the screen from being overu…

I had heard of this before, but didn't know that screensavers were designed to prevent that damage from happening. In this case, the bouncing DVD logo seems like an odd choice, as the way it's designed, there are certain pixels on the screen that it will never cross (corners, for example), which would fail to serve the desired purpose. Can someone explain?

It doesn't have to cross them. Showing a black screen won't burn it in. The problem is illuminated areas that stay that way for too long. The dvd logo itself just can't be in the same spot. They probably could have just had the tv turn off/show nothing. Maybe it would have confused users not knowing that the tv was still on.

Re: Bouncing DVD Logo

#175
post #165

Earlier quoted context omitted.

I never noticed a benefit over 70 or so. The flicker of 60 made my eyes bleed though. Then with LCDs 60 was fine.

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.…

AC power is 60hz so room lighting (especially florescent) also flickers at 60hz. It’s a sort of wagon wheel effect.

Re: Bouncing DVD Logo

#176
post #175
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.…

AC power is 60hz so room lighting (especially florescent) also flickers at 60hz. It’s a sort of wagon wheel effect.

I dropped a hint right there that the AC frequency is definitely not 60 Hz where I am.

Re: Bouncing DVD Logo

#177

Earlier quoted context omitted.

WTF? Mind blown. And I've been hacking the web for nearly 20 years now.

It's amazing how well the effect works. Here's a demo: https://jsbin.com/kuzolurapi/1/edit?html,output

it only moves horizontally on iOS.

Re: Bouncing DVD Logo

#178
post #32

Earlier quoted context omitted.

Probably more work to rip it out of your build pipeline than just reusing the config you use for all your other projects.

People use a build pipeline for small JS projects? I just open an editor in a directory and start typing.

If you usually build production ready services you might reuse your setup even if you just do a small proof of concept or fun project like this one.

Re: Bouncing DVD Logo

#179
post #68
post #60

As a historical note, the bouncing logo wasn't just for fun, but was important to prevent screen burn-in on CRTs. If you had a static image on a CRT for a long time, it could damage the phosphor. Sometimes you could even see the image when the screen was off! This was the original purpose of screensavers, which saved your screen from damage. Displaying a dynamic image prevented one part of the screen from being overu…

That you feel the need to inform us of this "historical fact" makes me feel especially old... having lived through the CRT -> LCD transition period when buying an LCD made going to LAN parties a lot easier

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.

Re: Bouncing DVD Logo

#180

Earlier quoted context omitted.

It lags pretty bad on my Pixel phone too..

Only tested on an iPhone, works fine at 60fps. You can open the standalone page at https://wwpzj.csb.app/ to avoid the whole codesandbox app running at the same time.

I am grateful for your effort and have no intention to troll or diminish you - in case it looks like that. But still: now in desktop Chrome logo bounces from the very bottom or right edges of window, which is great, but there are gaps at the left and top edges, so logo never reaches those two edges.

I beleieve you are quite competent in this, so for me it's just another illustration of how HTML/DOM ecosystem is broken in so many ways that it takes enormous effort to perform such a trivial task. Thank you and plase stop wasting your time on this)

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