4 ms·

I don’t understand this comment. Wayland has already been mentioned. macOS and Windows have both also made huge progress in this area. And iOS is the gold stand

I don’t understand this comment. Wayland has already been mentioned. macOS and Windows have both also made huge progress in this area. And iOS is the gold standard for modern UI responsiveness.

hedora 4y ago
All of those have worse latency than DOS or X11 (even when the latter are configured to prevent tearing by adding latency) Memory, power and compute efficiency have also regressed badly vs. those systems. Carmack explains how if would be possible to have tear free, framerate level updates "if only" people would upgrade to 8MB of video ram and 100MB/sec busses. I'm old enough to remember the DOS days. On average, iOS apps are significantly less responsive than old 386 DOS, SDL or X11 programs.
- mananaysiempre 4y ago
  > Carmack explains how if would be possible to have tear free, framerate level updates "if only" people would upgrade to 8MB of video ram and 100MB/sec busses. With 1280x1024x8@75Hz and a single blit per frame. For 32-bit colour like you have virtually everywhere these days, multiply that bandwidth by four; for a 2560x1600 screen like the one I’m writing this on, multiply further by three and a bit; (admittedly,) for 60Hz instead of 75Hz, multiply by 4/5. All in all, this laptop I’m sitting before needs a gigabyte per second to just barely sustain one blit per frame. And it needs a full framebuffer of video RAM (15M bytes) for the pretty security-message crossfade, probably at least a couple framebuffers per tab for the tiled renderer in the browser, something in that ballpark so that I can smoothly scroll through a PDF I’m reading and not wait for it to rasterize... If I open a Chinese webpage, how much video RAM for the subpixel-positioned glyph cache, I wonder? And remember, none of that OpenGL floating-point-colour nonsense, that would multiply both memory and bandwidth by three again. Carmack could have probably squeezed a smooth UI into a 8M main + 8M (16M?) video RAM, 100 MB/s machine at 800x600, if the UI you wanted was the one from 1995. And that would honestly be grand, I’d be happy to see that on a 2005-specced machine, even. But let’s not kid ourselves—we do in fact demand much more from our computers now than we did then.
- Jasper_ 4y ago
  DOS ran on VGA, with a resolution of 640x480, with 256 colors per pixel (307,200 bytes per frame). The iPhone 14 has a resolution of 2532x1170 [0], at 32 bits per pixel (11,849,760 bytes per frame) -- about two orders of magnitude higher. Not to mention the lack of compositing and multitasking on DOS. Compositing was a big feature. We started trading off throughput for latency because our old approaches just wouldn't scale. There are lots of other factors, for sure, but that's a pretty big one! [0] https://ioshacker.com/iphone/resolution-of-iphone https://ioshacker.com/iphone/resolution-of-iphone

I don’t understand this comment. Wayland has already been mentioned. macOS and Windows have both also made huge progress in this area. And iOS is the gold standard for modern UI responsiveness.

hedora 4y ago

All of those have worse latency than DOS or X11 (even when the latter are configured to prevent tearing by adding latency) Memory, power and compute efficiency have also regressed badly vs. those systems. Carmack explains how if would be possible to have tear free, framerate level updates "if only" people would upgrade to 8MB of video ram and 100MB/sec busses. I'm old enough to remember the DOS days. On average, iOS apps are significantly less responsive than old 386 DOS, SDL or X11 programs.

mananaysiempre 4y ago
> Carmack explains how if would be possible to have tear free, framerate level updates "if only" people would upgrade to 8MB of video ram and 100MB/sec busses. With 1280x1024x8@75Hz and a single blit per frame. For 32-bit colour like you have virtually everywhere these days, multiply that bandwidth by four; for a 2560x1600 screen like the one I’m writing this on, multiply further by three and a bit; (admittedly,) for 60Hz instead of 75Hz, multiply by 4/5. All in all, this laptop I’m sitting before needs a gigabyte per second to just barely sustain one blit per frame. And it needs a full framebuffer of video RAM (15M bytes) for the pretty security-message crossfade, probably at least a couple framebuffers per tab for the tiled renderer in the browser, something in that ballpark so that I can smoothly scroll through a PDF I’m reading and not wait for it to rasterize... If I open a Chinese webpage, how much video RAM for the subpixel-positioned glyph cache, I wonder? And remember, none of that OpenGL floating-point-colour nonsense, that would multiply both memory and bandwidth by three again. Carmack could have probably squeezed a smooth UI into a 8M main + 8M (16M?) video RAM, 100 MB/s machine at 800x600, if the UI you wanted was the one from 1995. And that would honestly be grand, I’d be happy to see that on a 2005-specced machine, even. But let’s not kid ourselves—we do in fact demand much more from our computers now than we did then.
Jasper_ 4y ago
DOS ran on VGA, with a resolution of 640x480, with 256 colors per pixel (307,200 bytes per frame). The iPhone 14 has a resolution of 2532x1170 [0], at 32 bits per pixel (11,849,760 bytes per frame) -- about two orders of magnitude higher. Not to mention the lack of compositing and multitasking on DOS. Compositing was a big feature. We started trading off throughput for latency because our old approaches just wouldn't scale. There are lots of other factors, for sure, but that's a pretty big one! [0] https://ioshacker.com/iphone/resolution-of-iphone https://ioshacker.com/iphone/resolution-of-iphone