- From: Gérard Talbot <css21testsuite@gtalbot.org>
- Date: Wed, 14 Nov 2012 20:59:32 -0500
- To: "Public CSS testsuite mailing list@w3.org" <public-css-testsuite@w3.org>
> background-size-021: the image should be scaled from 98px wide by 99px > tall to 100px wide and 100px tall. There is a rounding of fractional > pixels: it's actually difficult to figure out what happens with > calculations here. When I set 'background-size: 99% 99%' in that test, > then I should see a 1px wide red vertical line at the right of the cat > with a 1px tall red horizontal line below the cat but this is not > happening in Opera 12.10. So, the failure in Chrome 23.0.1271.64 is most > likely only due to rounding effects of a fraction in the calculation. > The way to work around this difficulty would be to create an image whose > dimensions won't be subject to fraction when being scaled. The cat image > does not have ideal dimensions for scaling: 98px wide by 99px height. > NeedsWork=Precision > best is to use an image dimensions > that will scale without creating fractional pixel and [when!] > rounding up or down > to use an image which, when > scaled up or down, will not involve fractions [http://lists.w3.org/Archives/Public/public-css-testsuite/2012Nov/0022.html] It seems that the original cat image from Ian "Hixie" Hickson was 62px by 65px: http://www.hixie.ch/resources/images/astrophy/ and there are other versions with 1:1 ratio, like 64px by 64px or 200px by 200px. We should use/copy some of these images and maybe we should be looking for other images with an intrinsic ratio of 1:1 and with an intrinsic ratio of 2:1 which could be more reliably rescaled without causing unneedlessly fractions. Also, if such images could fill both dimensions, this would be a plus. The cat image has some blank areas. Gérard -- Contributions to the CSS 2.1 test suite: http://www.gtalbot.org/BrowserBugsSection/css21testsuite/ CSS 2.1 Test suite RC6, March 23rd 2011: http://test.csswg.org/suites/css2.1/20110323/html4/toc.html CSS 2.1 test suite harness: http://test.csswg.org/harness/ Contributing to to CSS 2.1 test suite: http://www.gtalbot.org/BrowserBugsSection/css21testsuite/web-authors-contributions-css21-testsuite.html
Received on Thursday, 15 November 2012 02:00:05 UTC