Running Qt/KDE Atop An OpenGL Stack

[yotambien]

I don't use KDE or any other desktop manager. Still, back when I did, I remember having to configure separately Openoffice. Also I remember vaguely doing something with Firefox and xpdf. Actually it was xpdf the application that one happy day suddenly chose to ignore my previous settings...

IF today _all_ applications actually honour the system wide (or what you would hope to be system wide) settings, and those can be easily set up within a GUI, we (or at least I) have something to celebrate.

[BlackStar]

Nowadays, if you don't want to use "subpixel rendering" you have to hack the hell out of obscure configuration files

Using Gnome, I can disable subpixel AA with 3 clicks (Appearance -> Fonts -> Best Shapes). Both GTK and Qt applications seem to honor this setting (this wasn't the case with Ubuntu 8.10-, but seems to be working as advertized in 9.04 - finally!) Even OpenOffice and VirtualBox revert to greyscale AA when they didn't before.

It does not, however, improve the quality of anything.

Microsoft, Apple and Gnome have done extensive usability studies on text rendering. They didn't pull subpixel AA out of their collective asses.

See, for example, here:

"Overall, the study participants read the ClearType sentences statistically reliably faster than the sentences rendered in black & white (called aliased here). The magnitude of effect is approximately 5%. [...]

Additionally, the participants made more correct responses when the text was presented in ClearType. [...] There was a statistically reliable accuracy improvement ClearType with a smaller effect magnitude of about 2%."

And life is surely easier if you like it than if you don't.

Any default setting will alienate some people, that's a given. Fortunately, you are using Linux - changing a setting is relatively easy (no need to be an admin, like on Windows); you can report an issue and request a different default; you can contribute to your favorite distro to the point they let you change the default; you can even roll your own distro with you own defaults, if you wish!

[yotambien]

Using Gnome, I can disable subpixel AA with 3 clicks (Appearance -> Fonts -> Best Shapes). Both GTK and Qt applications seem to honor this setting (this wasn't the case with Ubuntu 8.10-, but seems to be working as advertized in 9.04 - finally!) Even OpenOffice and VirtualBox revert to greyscale AA when they didn't before.

Yes, as I said, this is something to celebrate. Massive improvement.

Microsoft, Apple and Gnome have done extensive usability studies on text rendering. They didn't pull subpixel AA out of their collective asses.

I was aware of those. Well, to be honest, I don't know up to what point the Gnome crowd did any serious stuff on this front (do they have the resources to do it?). The link you provided is very interesting; unfortunately I don't have access to that journal, I am very curious (somebody here could PM it to me? ). From the abstract:

"Four experiments measured the effects of subpixel addressing (Microsoft's ClearType) relative to standard (aliased) font-rendering techniques."

So it's not clear to me what were they comparing. Deactivating subpixel rendering can be disastrous if the font is of mediocre quality. The automatically hinted fonts are usually horrible, only the manually, well hinted ones give the nicest results. I have a hard time believing that people find more legible a well hinted font at a right size (critical) than a clear type one. But sure, it may very well be true, and I really believe that the majority of people prefer clear type. I'm OK with that as long as I have the choice and that choice is simple to make.

Any default setting will alienate some people, that's a given. Fortunately, you are using Linux - changing a setting is relatively easy (no need to be an admin, like on Windows); you can report an issue and request a different default; you can contribute to your favorite distro to the point they let you change the default; you can even roll your own distro with you own defaults, if you wish!

I'm not as optimistic as you are. And you have acknowledged that in the past things weren't as straightforward as you and energyman describe for the current situation. At work I use OpenSuse (some version, I don't remember) and I can't change it to my liking; not in an easy way, at least. Even if I banged somebody in some mailing list that machine is not going to be upgraded any time soon. In practical terms, linux distributions shipped before _insert date here_ are crippled in a way that you can't easily choose the font rendering. I don't want to enter into rant mode, so let's forget about rolling my own distro, OK?

[deanjo]

So yes, "subpixel rendering" is important, but only because a lot of people (the majority, perhaps?) care about it.

Well I would venture to say a large majority don't even know about it. They simply use what is first presented to them.

[deanjo]

I'm not as optimistic as you are. And you have acknowledged that in the past things weren't as straightforward as you and energyman describe for the current situation. At work I use OpenSuse (some version, I don't remember) and I can't change it to my liking; not in an easy way, at least. Even if I banged somebody in some mailing list that machine is not going to be upgraded any time soon. In practical terms, linux distributions shipped before _insert date here_ are crippled in a way that you can't easily choose the font rendering. I don't want to enter into rant mode, so let's forget about rolling my own distro, OK?

Your correct, it is disabled by default for potential patent infringing reasons in openSUSE and a few others. It is also disabled by default by the upstream freetype2 folks for the same reasons. If you wish to enable it there is a wiki entry with a one-click install for it. http://opensuse-community.org/SubpixelHinting

[yotambien]

Your correct, it is disabled by default for potential patent infringing reasons in openSUSE and a few others. It is also disabled by default by the upstream freetype2 folks for the same reasons. If you wish to enable it there is a wiki entry with a one-click install for it. http://opensuse-community.org/SubpixelHinting

Oooh, I had completely forgotten about this issue (bad memories fade away). It's true, my first attempts at having decent fonts involved compiling a library (freetype I guess) to include the bytecode interpreter. Shortly after (Etch time more or less) Debian included it by default, and you only had to change some configuration files and tell fontconfig to use it.

This is, to some extent, surprising. I always had the feeling that the folks at Debian legal were extremely cautious about these things, and yet it's just the commercial distributions the ones avoiding the interpreter (or not just them?). Of course, it makes sense that they prefer to stay free of any possible litigation.

The patents, by the way, are held by Apple, and affect both antialiasing lovers and haters. The guys at freetype explain it here:

http://www.freetype.org/patents.html

My favourite rants about subpixel smoothing are those of Tuomo V:

http://modeemi.fi/~tuomov/b//archive.../17/T20_15_31/

http://modeemi.fi/~tuomov/b/archives.../20/T13_47_17/

In the first of them he gives the following link where you can see what are the differences among using no hinting, hinting and using the interpreter, for both antialiased and non antialiased fonts (bottom of the page):

http://mail.gnome.org/archives/gtk-d.../msg00429.html

Again, if they really managed to sort all this out with a simple mouse click they are heroes.


PS. To install the OpenSuse packages you have to log in as root, which is a no-no at work.

[RealNC]

PS. To install the OpenSuse packages you have to log in as root, which is a no-no at work.

Unpacking to your home dir and using LD_PRELOAD is your friend

[BlackStar]

Apple's patents end this October or so (there was an announcement in the FreeType list, a few months ago).

And there was much rejoicing!

[deanjo]

Apple's patents end this October or so (there was an announcement in the FreeType list, a few months ago).

And there was much rejoicing!

Well actually you have to take a look at the last date on the given patent. With subpixel hinting this would be US5325479: Method and apparatus for moving control points in displaying digital typeface on raster output devices

Which was given submitted May 28, 1992. So realistically FreeType won't be in the free and clear until 2012 and I wouldn't count on any mainstream distro enabling it by default until that time.

[Ex-Cyber]

Well actually you have to take a look at the last date on the given patent. With subpixel hinting this would be US5325479: Method and apparatus for moving control points in displaying digital typeface on raster output devices

Which was given submitted May 28, 1992. So realistically FreeType won't be in the free and clear until 2012 and I wouldn't count on any mainstream distro enabling it by default until that time.

If you look up that patent in the USPTO database, it says:

[*] Notice: The portion of the term of this patent subsequent to October 13, 2009 has been disclaimed.