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diff --git a/Master/texmf-dist/doc/fonts/gnu-freefont/TROUBLESHOOTING b/Master/texmf-dist/doc/fonts/gnu-freefont/TROUBLESHOOTING new file mode 100644 index 00000000000..a7af2225554 --- /dev/null +++ b/Master/texmf-dist/doc/fonts/gnu-freefont/TROUBLESHOOTING @@ -0,0 +1,115 @@ + Troubleshooting GNU FreeFont + +So your text looks lousy, although you installed FreeFont and you seem to be +using it. What do you do? + +Before you blame the problem on FreeFont, take the time to double-check that +the text you are looking at is really rendered with FreeFont. + +Be aware that not all Unicode characters are supported by FreeFont, and +even characters supported by one face, such as Serif, might not be +supported by other faces such as Sans. + +Also, some systems have settings that strongly affect the rendering +of fonts. It may be worth tweaking these. + +glyph substitution +================== + +When given the task of displaying characters in text, modern font rendering +software usually tries to display *something*, even if the font it is +*supposed* to be using does not contain glyphs for all the characters in the +text. The software will snoop through all the fonts on the system to find +one that has a glyph for the one missing in the desired font. So although +you have specified FreeSans-bold, you may be looking at a letter from quite +a different font. + +First double-check that the font in question really contains the character +in question. If you don't have font development software, this can be +tricky. In the case of FreeFont, you can check if a given character +range is supported: <http://www.gnu.org/software/freefont/coverage.html> + +Next double-check that your application (web browser, text editor, etc) +has indeed been properly instructed to use the font. + +Then double-check that the font is really installed in the system. +(This depends on the operating system, of course.) + +Linux and Unix +============== + +Modern Linux systems use a system called fontconfig, which maintains a font +cache, for efficiency. + +The font cache can really complicate font installation and troubleshooting +however. It can happen that when a font is newly installed, what is +displayed is coming out of an old cache entry rather than the new font. + +Just what to do depends on how and where the font was installed. + +Fonts installed system-wide are usually put in a directory such as + /usr/share/fonts/ +the font cache for these might be in + /var/cache/fontconfig/ +Fonts installed just for one user account will typically be in + ~/.fonts/ +and the cache will be + ~/.fontconfig/ + +You can clean your local cache merely by emptying the directory + ~/.fontconfig/ +In any case, to clean the cache, you can use the fontconfig command + fc-cache -vf +If run as root, it will clean the system cache, if run as a normal user, +it cleans only the normal user's cache. + +The procedure for local fonts is: + 1) shut off any program using the fonts in question + 2) clean the cache + 3) re-start the program +The procedure for system-wide fonts is: + 1) log out of the X Windows session + 2) in a console, clean the cache + 3) log in to an X Windows session + +LibreOffice / OpenOffice +======================== +These products have their own font rendering libraries, which have +idiosyncratic behavior. + +It has recently been reported that as of LibreOffice 3.5.1, font features +are disabled for OpenType fonts. If you use FreeFont with these products, +you may want to install the TrueType versions of the fonts. + +Windows +======= + +The most common complaint has to do with "blurry text". There are two +causes. + +The first is that ClearType smoothing is turned off. The best way to check +is to use the native Windows Web browser. Do a search for "ClearType Tuner". +The Microsoft pages install a tuner for ClearType. A security block notice +will appear at the top of the window--you have to allow the installation. +Then check the box "Turn on ClearType". The change happens immediately. + +The secont cause is that the FreeFont version with cubic spline outlines is +installed. As of the 2012 GNU FreeFont release, the TrueType builds have +quadratic splines, which work best with Windows' rendering software. + TTF (TrueType) quadratic splines Windows 7, Vista, Windows XP. + OTF (OpenType) cubic splines Linux, Mac + +Note also: Firefox has a setting for ClearType: + gfx.font_rendering.cleartype_params.rendering_mode +A value of 2 sets it to old-style GDI rendering, while -1 is the default. + +reporting problems +================== + +If you really think you're seeing a bug in FreeFont, or if you have +a suggestion, consider opening a problem report at + https://savannah.gnu.org/bugs/?group=freefont +It is best that you make a Savannah account and log in with that, so +you can be e-mailed whenever changes are made to your report. + +$Id: troubleshooting.txt,v 1.10 2011-07-16 08:38:06 Stevan_White Exp $ |