When using 'text-rendering:optimiseLegibility' with OSX(10.6.8), Safari (5.1) and Chrome (14.0) to render truetype fonts, the letter spacing of text is rendered inferior than with 'text-rendering:optimiseLegibility' toggled off. Presumably WebCore is imposing it's own hinting(?) onto the OSX text rendering? The result imo is inferior text letter spacing.
Do you have a test case for this that you could link to, or ideally attach to this bug?
please see http://code.newtypography.co.uk/?p=1320 for explanation and screenshots. (In reply to comment #1) > Do you have a test case for this that you could link to, or ideally attach to this bug?
This doesn't help much. To investigate this issue, we need to know exactly what font you are using, with which size, page background, whether there are plug-ins on the page, and more. The best way to communicate such information is by providing a complete test case. Also, I'm assuming that your test actually uses "optimizeLegibility", not "optimiseLegibility".
ok will provide a complete test case. The css in my test pages is "optimizeLegibility". (In reply to comment #3) > This doesn't help much. To investigate this issue, we need to know exactly what font you are using, with which size, page background, whether there are plug-ins on the page, and more. > > The best way to communicate such information is by providing a complete test case. > > Also, I'm assuming that your test actually uses "optimizeLegibility", not "optimiseLegibility".
I have put a test page at http://newtypography.co.uk/fonttests/renderfonttest.html If you need more please let me know specifics. (In reply to comment #3) > This doesn't help much. To investigate this issue, we need to know exactly what font you are using, with which size, page background, whether there are plug-ins on the page, and more. > > The best way to communicate such information is by providing a complete test case. > > Also, I'm assuming that your test actually uses "optimizeLegibility", not "optimiseLegibility".
I believe that this was fixed in <http://trac.webkit.org/r95070>. Can you please test with a WebKit nightly build of a r95070 or later? Thanks!
No this is not the same issue :) It looks as if Webkit on OSX is adjusting the spacing between letters of rendered text. These adjustments are creating inferior letter spacing on webfonts. On Linux Chrome & ChromeOS the spaciong adjustments seem to be made between words, not letters. This makes sense. OSX implementation seem to be wrong. (In reply to comment #6) > I believe that this was fixed in <http://trac.webkit.org/r95070>. Can you please test with a WebKit nightly build of a r95070 or later? Thanks!
(In reply to comment #7) > No this is not the same issue :) I see a significant difference between how glyphs in your test case are spaced in Safari 5.1 and how they’re spaced in the latest WebKit nightly build. Are you not?
Note that Gecko on OS X has 'optimizeLegibility' turned ON by default (and you can't turn it off). On the other hand, Opera doesn't support that property, so far. See https://developer.mozilla.org/en/CSS/text-rendering for a description of the property. Is there a similar Apple doc ? I may have missed it… That being said, * I see a slight difference - improved (!) rendering – on the latest Webkit compared to Safari 5.1 * I see virtually no difference between the latest WebKit and Fx 7 and Gecko nightly builds. The spacing between words is slightly looser on Gecko – it looks like Webkit tightens the white-space slightly whereas Gecko does not. * the Coda font has a weird behaviour in WebKit - the spacing is looser with 'optimizeLegibility' than without. I would expect the opposite. The text run without optimisation on WebKit looks the same as Gecko (which has optimisation ON by default) Tested on 10.6.8 - took some screenshots and overlayed them in Photoshop.
Many thanks. Under latest nightly builds of Webkit and Google Canary, the issue is now fixed :) text rendering is now optimised, and comparable to Gecko. Re: Coda font. this font has no kerning pairs for lowercase characters. Hence why it's letter spacing doesn't tighten under 'optimizeLegibility'. However, does optimizeLegibility apply any auto-hinting or that would explain the looser (but better?) spacing under optimizeLegibility? (In reply to comment #9) > Note that Gecko on OS X has 'optimizeLegibility' turned ON by default (and you can't turn it off). On the other hand, Opera doesn't support that property, so far. > > See https://developer.mozilla.org/en/CSS/text-rendering for a description of the property. Is there a similar Apple doc ? I may have missed it… > > That being said, > * I see a slight difference - improved (!) rendering – on the latest Webkit compared to Safari 5.1 > * I see virtually no difference between the latest WebKit and Fx 7 and Gecko nightly builds. The spacing between words is slightly looser on Gecko – it looks like Webkit tightens the white-space slightly whereas Gecko does not. > > * the Coda font has a weird behaviour in WebKit - the spacing is looser with 'optimizeLegibility' than without. I would expect the opposite. The text run without optimisation on WebKit looks the same as Gecko (which has optimisation ON by default) > > Tested on 10.6.8 - took some screenshots and overlayed them in Photoshop.
Marking WORKSFORME per this comment. Thank you for testing! Please send questions about WebKit behavior to webkit-help mailing list: http://www.webkit.org/contact.html