- From: Tab Atkins Jr. <jackalmage@gmail.com>
- Date: Thu, 10 May 2012 16:19:13 +0200
- To: Simon Pieters <simonp@opera.com>
- Cc: whatwg@whatwg.org, Edward O'Connor <eoconnor@apple.com>
On Thu, May 10, 2012 at 3:47 PM, Simon Pieters <simonp@opera.com> wrote: > On Thu, 10 May 2012 15:24:28 +0200, Tab Atkins Jr. <jackalmage@gmail.com> > wrote: >> CSS3 Images has the image-resolution property, which lets you tell the >> browser what resolution to display the image at (that is, how it >> should determine the automatic size). You can say "image-resolution: >> from-image;" to get it to use the image's native resolution, whatever >> it is. So, we need to add a rule to the UA stylesheet that says >> "img[srcset] { image-resolution: from-image; }". > > Do we want from-image here? Or do authors prefer to serve 96dpi images that > are bigger, and specify the intended dpi in the markup? Can you clarify what you mean by this? Do you mean serving a 10inch wide image at 96dpi rather than a 5inch wide image at 192dpi, and then telling the browser to scale it by the x factor? The two are identical in the image's data (they're all 960 pixels wide), only the metadata differs. I suspect both: 1. A lot of authors would find it very confusing if they couldn't save an image at 300dpi and have it just work, and 2. A lot of authors will be confused to discover that that they have to save their image as 300dpi to get it to work. >> For two, I'm not sure that it's particularly obvious that when you say >> "2x", you should make sure your image was saved as 196dpi. You have >> to already know what the default resolution is. As well, I think that >> values like 300dpi are pretty common, and they don't map to integral >> 'x' values. If people say "screw it" and use "3x", this'll be >> slightly wrong and I think will cause ugly blurring. If we make this >> take <resolution>, people can just use the dpi unit. > > Can we just use CSS's 'dpi' instead? > > <img src="default.jpg" srcset="highres.jpg 300dpi"> If you take dpi, you might as well take all of the <resolution> units. There's only 3 so far - dpi, dpcm, and dppx. There's no good reason to limit to only one of them, since they're all constant multiples of each other. ~TJ
Received on Thursday, 10 May 2012 14:20:07 UTC