Open
Bug 1100217
Opened 10 years ago
Updated 2 years ago
Parts of UI text not subpixel-antialiased on Windows XP
Categories
(Core :: Graphics: Text, defect)
Tracking
()
UNCONFIRMED
People
(Reporter: jzef.marciniak, Unassigned)
Details
Attachments
(3 files)
User Agent: Mozilla/5.0 (Windows NT 5.2; WOW64; rv:33.0) Gecko/20100101 Firefox/33.0 Build ID: 20141113143407 Steps to reproduce: In Firefox 33.1.1 I noticed that the program uses alternately fonts with your own or a system ClearType in different places: All drop-down menu in addition to Bookmarks - ClearType Firefox Bookmarks but only the main menu - ClearType OS Bookmarks bar in the Bookmarks - ClearType Firefox Address bar - ClearType Firefox Tabs - ClearType OS Actual results: Firefox uses different types of ClearType Expected results: Firefox should only use the system ClearType
Updated•10 years ago
|
Component: Untriaged → Graphics: Text
Product: Firefox → Core
Comment 1•10 years ago
|
||
Can you provide a screenshot or more data indicating what you mean? What is "ClearType Firefox" ?
Flags: needinfo?(jzef.marciniak)
Reporter | ||
Comment 2•10 years ago
|
||
Yes, of course. Please compare the font on the picture to enlarge it. ClearType from WinXP is clearer. Firefox uses its own ClearType but unfortunately it is worse than that of WinXP.
Flags: needinfo?(jzef.marciniak)
Comment 3•10 years ago
|
||
Looks to me like we're using grayscale-only antialiasing instead of subpixel antialiasing. What Windows theme do you use? And did/does this not happen on Firefox 32? Does the issue go away if you go to about:config, and turn off layers.offmainthreadcomposition.enabled, then restart the browser?
Flags: needinfo?(jzef.marciniak)
OS: Windows Server 2003 → Windows XP
Summary: Still a problem with fonts → Parts of UI text not subpixel-antialiased on Windows XP
Reporter | ||
Comment 4•10 years ago
|
||
Thanks a lot for your help :-). After turn off (false) layers.offmainthreadcomposition.enabled and restart browser ClearType is only from OS WinXP :-) :-) :-) I am very happy. I do not remember whether 32 but in 33.0.2 if you disable hardware acceleration it also helped. Please read this: https://bugzilla.mozilla.org/show_bug.cgi?id=1092709
Flags: needinfo?(jzef.marciniak)
Reporter | ||
Comment 5•10 years ago
|
||
Yes, after change layers.offmainthreadcomposition.enabled to false Firefox use font with ClearType from WinXP except address bar. Font in address bar still use grayscale antialiasing. How switch to use sub-pixel?
Comment 6•10 years ago
|
||
Jonathan, do you know what's going on here? Why does OMTC affect what type of antialiasing we do in the first place?
Flags: needinfo?(jfkthame)
Comment 7•10 years ago
|
||
(In reply to :Gijs Kruitbosch from comment #6) > Jonathan, do you know what's going on here? Why does OMTC affect what type > of antialiasing we do in the first place? Someone like Bas or Roc can probably comment more usefully on this.
Flags: needinfo?(roc)
Flags: needinfo?(jfkthame)
Flags: needinfo?(bas)
With OMTC, we don't support component-alpha layers in the layer system unless you're using GPU accelerated compositing (D3D on Windows). My guess is that Jzef doesn't have GPU compositing. Jzef, can you attach about:support here to confirm that? Thanks! We can still draw with subpixel antialiasing as long as the text doesn't end up in a transparent buffer. That should be the case for the WinXP menus in the screenshot, or we can make it so. I will look into this.
Flags: needinfo?(roc)
Flags: needinfo?(jzef.marciniak)
Flags: needinfo?(bas)
Hmm, https://bugzilla.mozilla.org/show_bug.cgi?id=1092709#c5 suggests that Jzef does have GPU-accelerated compositing. Bas, can you confirm that OMTC with D3D9 supports component alpha?
Flags: needinfo?(bas)
Comment 10•10 years ago
|
||
(In reply to Robert O'Callahan (:roc) (Mozilla Corporation) from comment #9) > Hmm, https://bugzilla.mozilla.org/show_bug.cgi?id=1092709#c5 suggests that > Jzef does have GPU-accelerated compositing. > > Bas, can you confirm that OMTC with D3D9 supports component alpha? It -should- do you need me to investigate whether it's all working right?
Flags: needinfo?(bas)
I think it would be worth at least trying to reproduce the bug.
Flags: needinfo?(bas)
Reporter | ||
Comment 12•9 years ago
|
||
I have found this: Azure does not honor Windows cleartype setting, causing font issue in FF 17 http://bugzilla.mozilla.org/show_bug.cgi?id=814101 This is the same problem like in Firefox 17.0 and this probably has been fixed in 17.0.1. I found this Attachment: http://bugzilla.mozilla.org/attachment.cgi?id=686566 On this Attachment see that URL bar use different antialiasing: 17.0 - URL bar use grayscale (bad) 17.0.1 - URL bar use subpixel (good) In Firefox 34.0.5 have exactly the same problem like in Firefox 17.0 - URL bar still use grayscale antialiasing.
Flags: needinfo?(jzef.marciniak)
Comment 13•9 years ago
|
||
Alright, I've looked into this bug, it was a little hard to figure out but it boils down to two things: - Cairo Image surfaces do not support subpixel AA, since the browser chrome is a transparent layer it's an image surface. I have a patch for this. - Cairo doesn't support Subpixel AA to a transparent surface when the clip is not a region (i.e. not a bunch of pixel aligned rectangles). There's SVG clips applied to parts of the UI preventing them from getting subpixel AA with SVG (and for the record, also decreasing their performance).
Flags: needinfo?(bas)
Comment 14•9 years ago
|
||
So the second part as far as I can tell there's two things we can do: - Try and get rid of the SVG clip. - Try and add code to Cairo that sees whether the clip subsumes the extends of the glyphs being drawn, and ignore it if that's the case. For the latter as far as I can tell Cairo doesn't have any code at this point, but I suppose theoretically we could add it.
Flags: needinfo?(roc)
Flags: needinfo?(jmuizelaar)
Comment 15•9 years ago
|
||
(In reply to Bas Schouten (:bas.schouten) from comment #13) > Alright, I've looked into this bug, it was a little hard to figure out but > it boils down to two things: > > - Cairo Image surfaces do not support subpixel AA, since the browser chrome > is a transparent layer it's an image surface. I have a patch for this. > - Cairo doesn't support Subpixel AA to a transparent surface when the clip > is not a region (i.e. not a bunch of pixel aligned rectangles). There's SVG > clips applied to parts of the UI preventing them from getting subpixel AA > with SVG (and for the record, also decreasing their performance). The second part is not a regression right? Can we just do nothing?
Flags: needinfo?(jmuizelaar)
nsSVGIntegrationUtils::PaintFramesWithEffects has a "if (clipPathFrame && !isTrivialClip) {" case which does a PushGroup(COLOR_ALPHA). If we change that to gfxContext::PushGroupAndCopyBackground that should fix this I think. Bas, can you try that?
Flags: needinfo?(roc) → needinfo?(bas)
Comment 17•9 years ago
|
||
(In reply to Robert O'Callahan (:roc) (Mozilla Corporation) from comment #16) > nsSVGIntegrationUtils::PaintFramesWithEffects has a "if (clipPathFrame && > !isTrivialClip) {" case which does a PushGroup(COLOR_ALPHA). If we change > that to gfxContext::PushGroupAndCopyBackground that should fix this I think. > Bas, can you try that? It does not, it also makes sense that it doesn't, since Cairo just gives up on doing SubpixelAA on an image surface if there's a complex clip set on it, regardless of the content type of that surface.
Flags: needinfo?(bas) → needinfo?(roc)
(In reply to Bas Schouten (:bas.schouten) from comment #17) > It does not, it also makes sense that it doesn't, since Cairo just gives up > on doing SubpixelAA on an image surface if there's a complex clip set on it, > regardless of the content type of that surface. OK, then after the PushGroupAndCopyBackground, we should reset the clip somehow. E.g. we could reset it to the clip bounding-box. Or we can create a temporary gfxContext perhaps. The best way to do this is a gfxContext/Moz2D question really...
Flags: needinfo?(roc)
Reporter | ||
Comment 19•9 years ago
|
||
Reporter | ||
Comment 20•9 years ago
|
||
The problem still exists in version 40.0.2 but for some time I started using the Favorites menu in a different way - disable menu bar and click icon Display bookmarks from toolbar: https://bugzilla.mozilla.org/attachment.cgi?id=8651351 Bookmarks from menu bar - gray-scale AA Bookmarks from icon - subpixel AA
Updated•2 years ago
|
Severity: normal → S3
You need to log in
before you can comment on or make changes to this bug.
Description
•