[HOWTO]Freetype subpixel font rendering - lcd monitors Pt 2

[Infinality]

Even though I specifically pointed out that this particular patch (20101004-2) was probably broken, I still hate to have people spinning their wheels with problems and bugs. You guys are kind of my "beta testers" as I get the most feedback out of you. I check the Gentoo and Archlinux forums pretty regularly, but if you find an issue, feel free to make a post on my blog.

---

Also, on an unrelated note, I do like the Gibson filter you have been pushing { 0x1c, 0x38, 0x55, 0x38, 0x1c }, but I've found that at least on my monitor, it looks better with 0x60 in the middle. I think the FIR filter is very dependent on one's monitor contrast and gamma. On my monitor at work, I'm pretty sure the default Gibson filter would look much nicer. That's what you get when you buy a cheap monitor.

I'm working on a "membership/sigmoidal function" filter to precede the FIR filter, which does a pretty good job of duplicating the "Microsoft graininess", for those that prefer it that way. Basically it lowers values less than half intensity, and raises those above half intensity. If you want to tinker with it here it is:

val = 256.0 /(1.0+exp(-(10.0*(val/256.0-.5))));

It goes right before the line "pix = fir[0] + weights[0] * val;"

[PaulBredbury]

hate to have people spinning their wheels with problems and bugs

This single, huge, public thread is primarily for users, and tweakers (e.g. me). We want to know what works stably, and what doesn't, and what might look better with tweaks (and how to apply those tweaks). It's the best single source of info for the state-of-the-art in font rendering under Linux, AFAIK.

This thread, at risk of stating the obvious, serves a different purpose to a developer's forum or blog.

You changed freetype-add-subpixel-hinting-infinality-20101008-1.patch without calling it "-2", so I mentioned the filesize, to reduce confusion for the users.

The bug report on the firefox-crashing URL was already present.

Users will bitch & moan mercilessly, unless everything looks and works perfectly (which will never happen with fonts, until screens have 600+ DPI instead of ~120)

0x60

This looks even better, thanks.

[bi3l]

I've updated the overlay with the last patchset (including paul's gibson filter improved by infinality) but I haven't changed the version of the ebuild (you have to manually reemerge freetype after updating the overlay : emerge -1 freetype).

[jcTux]

I have no more crashes with okular.

[KejPi]

Wouldn't it be better to increase revision in this case so that people not following this thread know about changes?

[Infinality]

Wouldn't it be better to increase revision in this case so that people not following this thread know about changes?

I debated updating the version number here, and probably should have, but I figured since it was only an hour or so since the initial release, I could squeeze it in without anyone noticing.

[KejPi]

Well, a general rule says that you should not release two different things with the same ID (version number). At the end breaking this rule usually leads to some confusion.
But I don't want to complain - I am happy I can use it

[jsevilleja]

I've followed the wiki from lcd-filtering overlay with the fonts.conf from infinality, and now everything looks great. The only problem I've found, is, that in konsole, for example, when I'm typing, the bash "cursor" (I don't know if you guys call it "cursor") always goes two or three spaces ahead the keys. This also causes that the columns from the output of an "ls -la /" aren't aligned. How can I solve this? Thanks.

[KejPi]

The only problem I've found, is, that in konsole, for example, when I'm typing, the bash "cursor" (I don't know if you guys call it "cursor") always goes two or three spaces ahead the keys. This also causes that the columns from the output of an "ls -la /" aren't aligned. How can I solve this? Thanks.

I had this problem too - solved by choosing different font - monotype (I think this is the default one) does not work good.

[jsevilleja]

The only problem I've found, is, that in konsole, for example, when I'm typing, the bash "cursor" (I don't know if you guys call it "cursor") always goes two or three spaces ahead the keys. This also causes that the columns from the output of an "ls -la /" aren't aligned. How can I solve this? Thanks.

I had this problem too - solved by choosing different font - monotype (I think this is the default one) does not work good.

Sorry, but, exactly, how did you do that? Thanks

[KejPi]

Sorry, but, exactly, how did you do that? Thanks

Konsole -> Settings -> Set profiles -> Change -> Look -> Change font
Sorry for probably not correct translation, I am using localised version of KDE

[jsevilleja]

Sorry, but, exactly, how did you do that? Thanks

Konsole -> Settings -> Set profiles -> Change -> Look -> Change font
Sorry for probably not correct translation, I am using localised version of KDE

Solved, thanks. I thought that you were referring to change the local.conf.

[equilibrium]

Here's my ~/.fonts.conf for Infinality's rendering, which is the best rendering - but, use Infinality's own configuration, since he does a better job than me.

For posterity, here's my old ~/.fonts.conf for Ubuntu's rendering.

I just installed the changes/configs etc as suggested, rebooted and am just amazed at how much better fonts look

[tallica]

Another update: http://www.infinality.net/blog/?p=208 (Freetype Autohint Enhancement Patch)

Infinality, thanks!

[legogogo]

Why if firefox fonts is not like in other system? How it change?

http://lostpic.net/images/653ab65c1dce0 ... 23a105.png

[PaulBredbury]

There's a security bug and new 20101022 Infinality patches, so here's an all-in-one patch (freetype-2.4.3-20101023-2-brebs.patch.bz2) to apply to vanilla freetype2-2.4.3 - it includes:

• freetype-add-subpixel-hinting-infinality-20101022-1.patch
  freetype-enable-subpixel-hinting-infinality-20100909-1.patch
  freetype-enhance-emboldening-infinality-20101022-1.patch
  freetype-auto-autohint-for-non-tt-hinted-fonts-infinality-20101002-1.patch
  freetype-enhance-autohint-infinality-20101022-1.patch
  freetype-use-modified-gibson-filter-infinality-20101022-1.patch
  freetype-2.2.1-enable-valid.patch
  freetype2-git-20101023 (from: git diff a5a32c15c594d57b9a512e3b50721caedb5697bc), which includes the security fix.
  sed -i -r 's:.*(#.*TT_CONFIG_OPTION_SUBPIXEL_HINTING.*) .*:\1:' include/freetype/config/ftoption.h - to ensure that Infinality's experimental stuff is enabled
  sed -i -r 's:.*(#.*SYSTEM_ZLIB.*) .*:\1:' include/freetype/config/ftoption.h - To use system ZLIB
  rm -f include/freetype/config/ftoption.h.orig src/base/ftobjs.c.orig src/truetype/ttinterp.c.orig - To remove useless files

So, this is the latest of everything including the kitchen sink, in terms of patches to freetype2

[bi3l]

Updated LCD Filtering accordingly.

[tallica]

bi3l, Do you use the lcdfilter patch for poppler? I can't get Evince to use it...

[bi3l]

No, I have not maintained poppler's ebuild in LCD filtering for a while. Do you want me to update it ?

[tallica]

I've already bumped it in my local overlay. It cleanly apply to poppler 0.14.4 although Evince doesn't seem to care... all I get is monochrome antialiasing :/

EDIT:
Looks like Evince needs patching, I'm working on it right now.

[vnekontakta]

Hello! Yesterday after updating freetype library from lcd-filtering overlay i noticed that cyrillic small letter "у" looks broken in browser when html page using Trebuchet MS from corefont package (in both Firefox-3.6.9 and Chromium-7.0.517.41). When i downgraded from freetype-2.4.3 to 2.4.2 (same lcd-filtering overlay) problem is gone, but fonts looks not so good like with freetype-2.4.3. I use x86_64 system.

Screenshot from page http://www.linux.org.ru/ :
http://youpic.su/view.php?id=s001.youpi ... 36d635.png
Bigger: http://youpic.su/view.php?id=s001.youpi ... 4979f9.png

Or from here http://www.ienews.ru/pochemu_putin_krab.html :
http://youpic.su/view.php?id=s001.youpi ... 1f1726.png

Bold small letter looks fine.
In system this letter also broken:
http://youpic.su/view.php?id=s001.youpi ... af5a1f.png

[tallica]

Ok, I've found a patch: https://bbs.archlinux.org/viewtopic.php?id=82529 I've applied it against Evince 2.30.3, but I'm not 100% satisfied: http://ompldr.org/vNXd1bw/evince.png

Code: Select all

--- a/backend/pdf/ev-poppler.cc	Sun Oct 24 15:06:16 2010 +0200
+++ b/backend/pdf/ev-poppler.cc	Sun Oct 24 17:44:39 2010 +0200
@@ -379,10 +379,24 @@
 
 #ifdef HAVE_POPPLER_PAGE_RENDER
 	cairo_t *cr;
+	cairo_font_options_t *options;
 
 	surface = cairo_image_surface_create (CAIRO_FORMAT_ARGB32,
 					      width, height);
+
+	memset (cairo_image_surface_get_data (surface), 0xff,
+		cairo_image_surface_get_height (surface) *
+		cairo_image_surface_get_stride (surface));
+
+	options = cairo_font_options_create ();
+	cairo_surface_get_font_options (surface, options);
+	cairo_font_options_set_antialias (options, CAIRO_ANTIALIAS_SUBPIXEL);
+	cairo_font_options_set_subpixel_order (options, CAIRO_SUBPIXEL_ORDER_RGB);
+	cairo_font_options_set_hint_style (options, CAIRO_HINT_STYLE_NONE);
+	
 	cr = cairo_create (surface);
+	cairo_set_font_options (cr, options);
+	cairo_font_options_destroy (options);
 
 	switch (rc->rotation) {
 	        case 90:

Setting CAIRO_HINT_STYLE_NONE/FULL/SLIGHT doesn't seem to make any difference. Is there anything that I can improve?

EDIT:
Difference between Evince and Gnome-terminal rendering: http://ompldr.org/vNXd4aw

[PaulBredbury]

cyrillic small letter "у" looks broken in browser when html page using Trebuchet MS

Yeah, looks broken to me too. It's been reported in Infinality's new forum.

[mbar]

Inconsolata Medium (12 points) has also the letter "m" rendering broken.
EDIT: at least when it's colored (not black), do "ls -la" on directory with files with "m" in filename.

[pezed]

After updating the overlay and emerging world today I noticed my fonts looked bad. I reverted back to "bf61c65" which is from September and now things look back to how they should. Not sure whats going on here:

Example (load them in seperate tabs to quickly switch between them to see the differences):

Fonts how they look using "bf61c65" (what I consider to be "good" rendering):
http://www.imgbin.org/index.php?page=image&id=2720

Fonts using HEAD:
http://www.imgbin.org/index.php?page=image&id=2719

Notice how bad the bold e's appear, the bold s's appear too thin, overall the fonts seem too tall. Guess I'll just stick with the older revision for now but just curious, are these changes intentional or some misconfiguration on my end?
Thanks.