Freetype has (optionally) supported subpixel LCD filtering since v2.3.0, but libXft is still, as of v2.1.13, unable to make use of it. Attached (minor) changes teach libXft how to use it via an updated version of David Turner's patch. Significantly improves sub-pixel anti-aliased type on-screen, especially by getting rid of "color fringes". See: http://cvs.savannah.gnu.org/viewvc/freetype/freetype2/docs/CHANGES?revision=1.201&view=markup http://david.freetype.org/lcd/
Created attachment 163159 [details, diff] Patch to the libXft ebuild
Created attachment 163161 [details, diff] Goes in the files/ subdirectory
OK, I did some research on this. Found http://david.freetype.org/cleartype-patents.html -- describes the patent issues with this. Neither cairo nor qt4 use libXft, so this patch wouldn't make much difference if it were applied (according to Fredrik Höglund, KDE/X guy). I'm not interested in applying patches to our software that aren't applied upstream, so please pursue this at bugs.freedesktop.org in the xorg product if you would like to see it happen.
Donnie, Last paragraph from the URL you referenced: "And it'd be nice if both the upstream Xft and Cairo could use the newest LCD-specific FreeType APIs. I have even provided patches to do just that a loooong time ago; for some reason, these have never been integrated by the respective library maintainers. I hope some day they'll wake up (though my hope is pretty dim). I suspect that Linux distribution packagers are already applying these patches though..." This patch does exactly what David is suggesting - in fact, it's his patch. For whatever reason, they're not making the change upstream in Xft. I have zero interest in the politics - the fact is that right now many Gentoo users (including all KDE 3.x users) are suffering poor on-screen type rendering and this patch fixes it. With those users in mind, would the patch be acceptable conditional on an off-by-default use-flag? Is so, I'm willing to implement it. Ron
Maybe I was insufficiently clear about the x11 team's patch policy in my last comment. We do not add patches that are not upstream, conditional or not. This has nothing to do with politics and everything to do with patches adding additional maintenance work, conditional ones even more so. Please pursue this upstream if you want to see it in Gentoo.
bi3l, of the Gentoo Forums, is maintaining a Portage overlay with patched versions of Cairo and libXft that utilize FreeType's subpixel filtering. Here's the overlay: http://ogmrip.sourceforge.net/misc/gentoo-lcd-filtering.tar.bz2 Here's the forum topic with ongoing discussion: http://forums.gentoo.org/viewtopic-t-511382.html I've been using this overlay for many months and have been pleased with the quality of my fonts.
