https://bugzilla.novell.com/show_bug.cgi?id=213989 ------- Comment #1 from mfabian@novell.com 2006-10-20 10:09 MST ------- First some background information: freetype versions <= 2.2.1 always could do sub-pixel-hinting (the "coloured" rendering). David Turner seems to believe now that Microsoft has Patents for practically *everything* which has to do with sub-pixel-hinting: David Turner> I have been relunctant to publicly comment on this issue, but I think David Turner> it's the right time now, because while the news aren't so good, in my David Turner> opinion, the more people are aware of it, the better. I've also CC-ed David Turner> Keith Packard and Carl Worth to this message since this will have an David Turner> impact on the code they distribute. David Turner> David Turner> first of all, the reason why the patches were taken down is simply David Turner> because my ISP lost all the files on my "personal web space" hosted on David Turner> their servers. it seems I can't upload anything there anymore, and it David Turner> has all to do with incompetence, not malice. David Turner> David Turner> However, I've been reluctant to propagate the files through other David Turner> means, because I wanted to analyze the Microsoft patents. That's David Turner> mainly because I intended to move the LCD-filtering capability into David Turner> FreeType itself, and didn't want to be responsible for yet another David Turner> sub-marine patents that could make millions for MS in a few years, David Turner> once the technique is being used in all kinds of gizmos like mobile David Turner> phones and PDAs; incorporated by unsuspecting developers. David Turner> David Turner> And my final understanding is that the MS patents pretty cover *all* David Turner> cases of LCD-specific rendering we're interested in (there are David Turner> ClearType patents that clearly don't affect us). And by the way, this David Turner> includes the original LCD-specific code found in libXft, Cairo, and David Turner> probably the XRender implementation of your X11 Server, even without David Turner> my FIR-filter patch. David's complete mail here: http://lists.gnu.org/archive/html/freetype/2006-09/msg00064.html Almost everything we released up to CODE10 contains code for sub-pixel-hinting in freetype2, libXft, XRender, Cairo and could be affected by problems with patents concerning sub-pixel-hinting. Now David has introduced a new compile time option FT_CONFIG_OPTION_SUBPIXEL_RENDERING in freetype2. One has to explicitly define that option if one wants freetype2 to support sub-pixel-hinting. The upstream default does not define that option. The freetype2 version we currently have in STABLE (freetype2-2.2.1.20061013) already is like that. Currently the option is *not* defined in STABLE, i.e. we currently loose the capability for sub-pixel-hinting. Actually it is even worse that that: In order to make sub-pixel-hinting a compile time option *and* to move the LCD Filtering code from libXft and Cairo into freetype2, the current version of freetype2 does not work well with the current libXft and Cairo. libXft and Cairo still do some colour filtering on the rendered glyphs they get from freetype2. This leads to hideous results with freetype2, no matter whether the subpixel hinting option is compiled into freetype2 or not. If freetype2 has been compiled *without* sub-pixel-hinting, libXft nevertheless does some colour filtering if sub-pixel-hinting is enabled for example in KDE. This just leads very ugly glyphs which look extremely coloured for no good reason. Even if freetype2 has been compiled *with* sub-pixel-hinting, the fonts on our desktop still look strange. That is because some of the LCD filtering is done in freetype2 in that case and that doesn't work well with the extra filtering done in libXft and Cairo. David's complete mail here: http://lists.gnu.org/archive/html/freetype/2006-09/msg00069.html -- Configure bugmail: https://bugzilla.novell.com/userprefs.cgi?tab=email ------- You are receiving this mail because: ------- You are on the CC list for the bug, or are watching someone who is.

https://bugzilla.novell.com/show_bug.cgi?id=213989 ------- Comment #3 from mfabian@novell.com 2006-10-20 10:17 MST ------- http://lists.gnu.org/archive/html/freetype/2006-10/msg00004.html From: "David Turner" <david@freetype.org> Subject: Updated Cairo LCD patch To: freetype@nongnu.org Cc: Carl Worth <cworth@cworth.org> Date: Tue, 03 Oct 2006 11:07:06 +0200 Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="ISO-8859-1" X-Mailer: MessagingEngine.com Webmail Interface Just to tell you that I've udpated my latest patch to Cairo-1.0.4, this corrects a really nasty bug that would seemingly randomly switch between gray and LCD mode when rendering text. Now everything seems to work extremely well, and I'll be moving to newer version of the library. http://david.freetype.org/lcd/cairo-1.0.4-lcd-filter-2.patch Enjoy, - David Turner - The FreeType Project (www.freetype.org) -- Configure bugmail: https://bugzilla.novell.com/userprefs.cgi?tab=email ------- You are receiving this mail because: ------- You are on the CC list for the bug, or are watching someone who is.