gnome-shell doesn't support subpixel smoothing

[Alexey S. Ignatiev]

Currently Gnome Shell does not support LCD font smoothing and now the shell's fonts looks terrible. It is said in gnome-shell's sources that the reason is "clutter doesn't currently have the code to support ARGB masks". I don't know what the problem is, but I wrote a simple patch that implements subpixel antialiasing in gnome-shell. And it works fine for me. After testing it for about 2 weeks I don't see any problems with it.

[Ubuntu Foundations Team Bug Bot (crichton)]

The attachment "add-subpixel-smoothing.patch" of this bug report has been identified as being a patch. The ubuntu-reviewers team has been subscribed to the bug report so that they can review the patch. In the event that this is in fact not a patch you can resolve this situation by removing the tag 'patch' from the bug report and editing the attachment so that it is not flagged as a patch. Additionally, if you are member of the ubuntu-sponsors please also unsubscribe the team from this bug report.

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[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Ilja Sekler (ilja-sekler-)]

FYI: The upstream bug with a slightly different patch, which might work also for non-RGB panels is <https://bugzilla.gnome.org/show_bug.cgi?id=645433>.

[Ilja Sekler (ilja-sekler-)]

Got a chance to test the patch with g-s 3.2.1 on Fedora 16 with rebuilt freetype (the official Fedora's freetype package has subpixel redering disabled). Hope this is applicable to Ubuntu too: the big problem with a patched GNOME shell is that the fonts seem being rendered using lcdlegacy filter, with horrible color fringes. All other GNOME applications, Firefox etc. have beautiful Ubuntu-like font rendering (hintslight+subpixel+lcddefault).

[Ilja Sekler (ilja-sekler-)]

> the big problem with a patched GNOME shell is that the fonts seem
> being rendered using lcdlegacy filter, with horrible color fringes.

Please scratch that. I was misguided by very thin shapes of the default Cantarell font at small font sizes, which do result in strong color fringes even with lcddefault. Replacing Cantarell in gnome-shell.css with DejaVuSans makes color fringes almost disappear. This rules out lcdlegacy filter.

The patch works beautifully, my apologies for the noise.

[Alexey S. Ignatiev (2sev)]

It's nice to hear that, although I don't know when subpixel smoothing will
be implemented in the upstream.

On Fri, Feb 3, 2012 at 7:00 AM, Ilja Sekler <email address hidden> wrote:

> > the big problem with a patched GNOME shell is that the fonts seem
> > being rendered using lcdlegacy filter, with horrible color fringes.
>
> Please scratch that. I was misguided by very thin shapes of the default
> Cantarell font at small font sizes, which do result in strong color
> fringes even with lcddefault. Replacing Cantarell in gnome-shell.css
> with DejaVuSans makes color fringes almost disappear. This rules out
> lcdlegacy filter.
>
> The patch works beautifully, my apologies for the noise.
>

[Daniel van Vugt (vanvugt)]

This appears to still be an issue in Ubuntu 17.10. Although that might just be because libdrm on my machine reports "unknown" subpixel ordering for my monitor. So greyscale is the correct fallback...

Can anyone confirm if this bug was fixed?

[Didier Roche-Tolomelli (didrocks)]

The X11 hinting itself is fixed in old version of G-S, closing thus.
Note that there is another issue under wayland, referenced in https://bugs.launchpad.net/gnome-shell/+bug/1714459

[Daniel van Vugt (vanvugt)]

As Didier mentioned, this bug is actually still open, but only open for Wayland. So see bug 1714459 about that.