Bug 477444 – x11-libs/cairo[xlib-xcb] causes ugly font rendering in gtk (compared to cairo-1.12.14-r2)

• Status: RESOLVED FIXED
• Product: Gentoo Linux

[Description Alexandre Rostovtsev (RETIRED) 2013-07-20 03:44:16 UTC]

Created attachment 353684 [details]
emerge --info output

Updating from cairo-1.12.14-r2 to cairo-1.12.14-r3 causes the fonts in all gtk2 and gtk3 applications to be rendered quite ugly (too much hinting, too thin, and looks like the wrong subpixel order for my screen).

Both revisions were emerged with the same USE flags: X glib opengl svg xcb (-aqua) -debug -directfb -doc (-drm) (-gallium) (-gles2) -legacy-drivers -openvg (-qt4) -static-libs -valgrind

[Comment 1 Alexandre Rostovtsev (RETIRED) 2013-07-20 03:45:45 UTC]

Created attachment 353686 [details]
screenshot with cairo-1.12.14-r2

[Comment 2 Alexandre Rostovtsev (RETIRED) 2013-07-20 03:46:41 UTC]

Comment on attachment 353686 [details]
screenshot with cairo-1.12.14-r2

gedit-3.6 screenshot with cairo-1.12.14-r2 - this looks good on my monitor

[Comment 3 Alexandre Rostovtsev (RETIRED) 2013-07-20 03:47:42 UTC]

Created attachment 353688 [details]
screenshot with cairo-1.12.14-r3

gedit-3.6 screenshot with cairo-1.12.14-r3 - this looks terrible on my monitor

[Comment 4 Matt Turner 2013-07-20 04:39:45 UTC]

cairo-1.12.14-r2 says:

> # --disable-xcb-lib:
> # do not override good xlib backed by hardforcing rendering over xcb

and cairo-1.12.14-r3 silently adds

> +		$(use_enable xcb xlib-xcb) \

Regardless if this is your issue, we should revert this.

[Comment 5 Paul Bredbury 2013-07-20 13:17:44 UTC]

That new use_enable is wrong, take a look at the cairo compilation output - choice tidbits:

The following surface backends:
  XCB:           yes

The following functions:
  X11-xcb functions: no (disabled, use --enable-xlib-xcb to enable)

So for Gentoo there should/would be 2 use flags: xcb and xlib-xcb.

However, who actually *benefits* from --enable-xlib-xcb? On Nvidia, for me it's always been noticeably slower in firefox, in the simple operation of opening a new tab and having 9 preview panes drawn in the empty tab.

[Comment 6 Rafał Mużyło 2013-07-20 16:53:39 UTC]

There's also that little catch, that xlib-xcb (at least last time I've checked - granted it was awhile here) causes artifacts in some of the corner cases in firefox.

Though even if that's still valid, you never know with firefox whose fault is it.

[Comment 7 Alexandre Rostovtsev (RETIRED) 2013-07-21 20:07:06 UTC]

Emerging cairo-1.12.14-r3 with EXTRA_ECONF=--disable-xlib-xcb fixes the font rendering problem.

[Comment 8 Chí-Thanh Christopher Nguyễn 2013-07-21 23:21:35 UTC]

The reason why I enabled it is bug 441878 comment 9. But it appears that not all users benefit from this so I will make it optional in the next revbump, and NX packages need put blockers or documentation in place.

[Comment 9 Chí-Thanh Christopher Nguyễn 2013-07-22 01:22:49 UTC]

1.12.14-r4 now has xlib-xcb USE flag