diff options
author | Ingo Schwarze <schwarze@cvs.openbsd.org> | 2019-05-02 19:12:06 +0000 |
---|---|---|
committer | Ingo Schwarze <schwarze@cvs.openbsd.org> | 2019-05-02 19:12:06 +0000 |
commit | ae8c4bb878009df9f6047a3f9b46e24d2b42ec34 (patch) | |
tree | 476c8ca6f8267ed5aff430d9fb1b251880371930 /doc | |
parent | 55e9daa8670c65a0760a667a03a9b2c268c1f124 (diff) |
simplify Makefiles for use with docbook2mdoc-1.1.0
and regen for improved formatting:
correct linebreaks in literal displays; and new sentence, new line
Diffstat (limited to 'doc')
-rw-r--r-- | doc/xorg-docs/Makefile.bsd-wrapper | 9 | ||||
-rw-r--r-- | doc/xorg-docs/general/fonts/fonts.7 | 291 |
2 files changed, 192 insertions, 108 deletions
diff --git a/doc/xorg-docs/Makefile.bsd-wrapper b/doc/xorg-docs/Makefile.bsd-wrapper index 3bf1dd5d8..b3560cbe7 100644 --- a/doc/xorg-docs/Makefile.bsd-wrapper +++ b/doc/xorg-docs/Makefile.bsd-wrapper @@ -1,4 +1,4 @@ -# $OpenBSD: Makefile.bsd-wrapper,v 1.3 2019/04/30 21:37:43 schwarze Exp $ +# $OpenBSD: Makefile.bsd-wrapper,v 1.4 2019/05/02 19:12:04 schwarze Exp $ CONFIGURE_ARGS += --without-fop --without-xmlto @@ -13,12 +13,7 @@ beforeinstall: # maintainer target, not used duing build or install mdoc: .for n in ${MDOCS} - { \ - echo ".\\\" automatically generated with"; \ - echo ".\\\" docbook2mdoc ${n:T}.xml > ${n:T}.7"; \ - docbook2mdoc ${.CURDIR}/${n}.xml; \ - } > ${.CURDIR}/${n}.7 - sed -i 's/^\.Dt ${n:T:U} 1$$/.Dt ${n:T:U} 7/' ${.CURDIR}/${n}.7 + docbook2mdoc -s 7 ${.CURDIR}/${n}.xml > ${.CURDIR}/${n}.7 .endfor .include <bsd.xorg.mk> diff --git a/doc/xorg-docs/general/fonts/fonts.7 b/doc/xorg-docs/general/fonts/fonts.7 index 7075a2f5a..de6063f5a 100644 --- a/doc/xorg-docs/general/fonts/fonts.7 +++ b/doc/xorg-docs/general/fonts/fonts.7 @@ -1,5 +1,4 @@ -.\" automatically generated with -.\" docbook2mdoc fonts.xml > fonts.7 +.\" automatically generated with docbook2mdoc fonts.xml .Dd 16 March 2012 .Dt FONTS 7 .Os @@ -13,7 +12,8 @@ is aimed at the casual user wishing to install fonts in X11R6 the rest of the document describes the font support in more detail. .Pp -We assume some familiarity with digital fonts. If anything is not +We assume some familiarity with digital fonts. +If anything is not clear to you, please consult .Sx Appendix_background_and_terminology at the @@ -26,15 +26,18 @@ X11 that are not based on either XFree86 or X11R6.8 or later. .Pp The core X11 fonts system is directly derived from the fonts system included with X11R1 in 1987, which could only use monochrome bitmap -fonts. Over the years, it has been more or less happily coerced into +fonts. +Over the years, it has been more or less happily coerced into dealing with scalable fonts and rotated glyphs. .Pp Xft was designed from the start to provide good support for scalable -fonts, and to do so efficiently. Unlike the core fonts system, it +fonts, and to do so efficiently. +Unlike the core fonts system, it supports features such as anti-aliasing and sub-pixel rasterisation. Perhaps more importantly, it gives applications full control over the way glyphs are rendered, making fine typesetting and WYSIWIG display -possible. Finally, it allows applications to use fonts that are not +possible. +Finally, it allows applications to use fonts that are not installed system-wide for displaying documents with embedded fonts. .Pp Xft is not compatible with the core fonts system: usage of Xft @@ -48,7 +51,8 @@ system to access newly-installed fonts. .Ss Configuring Xft Xft has no configuration mechanism itself, it relies upon the .Lk http://www.fontconfig.org/ fontconfig -library to configure and customise fonts. That library is +library to configure and customise fonts. +That library is not specific to the X Window system, and does not rely on any particular font output mechanism. .Pp @@ -68,7 +72,8 @@ $ cp lucbr.ttf ~/.fonts/ .Ed .Pp Fontconfig will notice the new font at the next opportunity and rebuild its -list of fonts. If you want to trigger this update from the command +list of fonts. +If you want to trigger this update from the command line, you may run the command .Dq Nm fc-cache . .Bd -literal @@ -120,7 +125,8 @@ can be done with the following syntax: .Ed .Pp Another useful option is the ability to disable anti-aliasing (font -smoothing) for selected fonts. This can be done with the following +smoothing) for selected fonts. +This can be done with the following syntax: .Bd -literal <match target="font"> @@ -142,7 +148,8 @@ Anti-aliasing can be disabled for all fonts by the following incantation: </match> .Ed .Pp -Xft supports sub-pixel rasterisation on LCD displays. X11R6 should +Xft supports sub-pixel rasterisation on LCD displays. +X11R6 should automatically enable this feature on laptops and when using an LCD monitor connected with a DVI cable; you can check whether this was done by typing @@ -182,7 +189,8 @@ counterclockwise). .Sy Configuring applications .Pp A growing number of applications use Xft in preference to the core -fonts system. Some applications, however, need to be explicitly +fonts system. +Some applications, however, need to be explicitly configured to use Xft. .Pp A case in point is XTerm, which can be set to use Xft by using the @@ -211,11 +219,13 @@ anti-aliasing in case it was disabled by your Xft configuration file. .Pp Gnome applications and Mozilla Firefox will use Xft by default. .Ss Configuring the core X11 fonts system -Installing fonts in the core system is a two step process. First, +Installing fonts in the core system is a two step process. +First, you need to create a .Em font directory that contains all the -relevant font files as well as some index files. You then need to +relevant font files as well as some index files. +You then need to inform the X server of the existence of this new directory by including it in the .Em font path . @@ -226,9 +236,11 @@ The X11R6 server can use bitmap fonts in both the cross-platform BDF format and the somewhat more efficient binary PCF format. (X11R6 also supports the obsolete SNF format.) .Pp -Bitmap fonts are normally distributed in the BDF format. Before +Bitmap fonts are normally distributed in the BDF format. +Before installing such fonts, it is desirable (but not absolutely necessary) -to convert the font files to the PCF format. This is done by using the +to convert the font files to the PCF format. +This is done by using the command .Dq Nm bdftopcf , .Em e.g. @@ -279,7 +291,8 @@ to create an index file called There is, however, a big difference: .Dq Nm mkfontdir cannot -automatically recognise scalable font files. For that reason, you +automatically recognise scalable font files. +For that reason, you must first index all the font files in a file called .Pa fonts.scale . While this can be done by hand, it is best done @@ -307,7 +320,8 @@ later in this document. .Sy CID-keyed fonts .Pp The CID-keyed font format was designed by Adobe Systems for fonts -with large character sets. The CID-keyed format is obsolete, as it +with large character sets. +The CID-keyed format is obsolete, as it has been superseded by other formats such as OpenType/CFF and support for CID-keyed fonts has been removed from X11. .Pp @@ -321,14 +335,16 @@ font directory consists of putting it on the font path. .Pp The font path is an ordered list; if a client's request matches multiple fonts, the first one in the font path is the one that gets -used. When matching fonts, the server makes two passes over the font +used. +When matching fonts, the server makes two passes over the font path: during the first pass, it searches for an exact match; during the second, it searches for fonts suitable for scaling. .Pp For best results, scalable fonts should appear in the font path before the bitmap fonts; this way, the server will prefer bitmap fonts to scalable fonts when an exact match is possible, but will avoid scaling -bitmap fonts when a scalable font can be used. (The +bitmap fonts when a scalable font can be used. +(The .Dq Li :unscaled hack, while still supported, should no longer be necessary in X11R6.) .Pp @@ -349,7 +365,8 @@ added as a local font path entry. The symlink can be suffixed by attributes such as .Pf ' Ql unscaled Ns ', which will be passed through -to the underlying font path entry. The only exception is the newly +to the underlying font path entry. +The only exception is the newly introduced .Pf ' Ql pri Ns ' attribute, which will be @@ -384,7 +401,8 @@ setting the following font path: The .Dq Nm xset utility may be used to modify the font path for the -current session. The font path is set with the command +current session. +The font path is set with the command .Nm xset fp ; a new element is added to the front with .Nm xset +fp , @@ -417,12 +435,14 @@ after may be specified in the X server's .Pa xorg.conf -file. It is computed by appending all the +file. +It is computed by appending all the directories mentioned in the .Dq Li FontPath entries of the .Dq Li Files -section in the order in which they appear. If no font path is specified in a config file, the server uses a default +section in the order in which they appear. +If no font path is specified in a config file, the server uses a default value specified when it was built. .Bd -literal FontPath "/usr/local/fonts/Type1" @@ -446,11 +466,13 @@ this doesn't help, it is quite possible that you are trying to use a font in a format that is not supported by your server. .Pp X11R6 supports the BDF, PCF, SNF, Type 1, TrueType, and OpenType -font formats. However, not all X11R6 servers +font formats. +However, not all X11R6 servers come with all the font backends configured in. .Pp On most platforms, the X11R6 servers no longer uses font -backends from modules that are loaded at runtime. The built in +backends from modules that are loaded at runtime. +The built in font support corresponds to the functionality formerly provided by these modules: .Bl -bullet @@ -486,7 +508,8 @@ family, and bitmap versions of Courier, Times, Helvetica and some members of the Lucida family. .Pp In X11R6, a number of these fonts are provided in Unicode-encoded -font files now. At build time, these fonts are split into font +font files now. +At build time, these fonts are split into font files encoded according to legacy encodings, a process which allows us to provide the standard fonts in a number of regional encodings with no duplication of work. @@ -505,7 +528,8 @@ is a Unicode-encoded version of the standard .Dq Li fixed font with added support for the Latin, Greek, Cyrillic, Georgian, Armenian, IPA -and other scripts plus numerous technical symbols. It contains over +and other scripts plus numerous technical symbols. +It contains over 2800 glyphs, covering all characters of ISO\ 8859 parts 1-5, 7-10, 13-15, as well as all European IBM and Microsoft code pages, KOI8, WGL4, and the repertoires of many other character sets. @@ -536,7 +560,8 @@ is normally an alias for .Ss The ClearlyU Unicode font family The ClearlyU family of fonts provides a set of 12\ pt, 100\ dpi proportional fonts with many of the glyphs needed for -Unicode text. Together, the fonts contain approximately 7500 glyphs. +Unicode text. +Together, the fonts contain approximately 7500 glyphs. .Pp The main ClearlyU font has the XLFD .Bd -literal @@ -559,7 +584,8 @@ Additional ClearlyU fonts include The .Em Alternate Glyphs font contains additional glyph shapes that -are needed for certain languages. A second alternate glyph font will +are needed for certain languages. +A second alternate glyph font will be provided later for cases where a character has more than one commonly used alternate shape .Pf ( Em e.g. @@ -574,7 +600,8 @@ The .Em Arabic Extra font contains the glyphs necessary for characters that don't have all of their possible shapes encoded in -ISO\ 10646. The glyphs are roughly ordered according to the order +ISO\ 10646. +The glyphs are roughly ordered according to the order of the characters in the ISO\ 10646 standard. .Pp The @@ -587,7 +614,8 @@ X11R6 includes all the scalable fonts distributed with X11R6. .Sy Standard Type\e1 fonts .Pp The IBM Courier set of fonts cover ISO\ 8859-1 and -ISO\ 8859-2 as well as Adobe Standard Encoding. These fonts have +ISO\ 8859-2 as well as Adobe Standard Encoding. +These fonts have XLFD .Bd -literal -adobe-courier-medium-*-*--0-0-0-0-m-0-*-* @@ -599,7 +627,8 @@ and reside in the font files .Ed .Pp The Adobe Utopia set of fonts only cover ISO\ 8859-1 as well as -Adobe Standard Encoding. These fonts have XLFD +Adobe Standard Encoding. +These fonts have XLFD .Bd -literal -adobe-utopia-*-*-normal--0-0-0-0-p-0-iso8859-1 .Ed @@ -610,7 +639,8 @@ and reside in the font files .Ed .Pp Finally, X11R6 also comes with Type\ 1 versions of Bitstream -Courier and Charter. These fonts have XLFD +Courier and Charter. +These fonts have XLFD .Bd -literal -bitstream-courier-*-*-normal--0-0-0-0-m-0-iso8859-1 -bitstream-charter-*-*-normal--0-0-0-0-p-0-iso8859-1 @@ -624,7 +654,8 @@ and reside in the font files X11R6 includes the .Em Luxi family of scalable fonts, in both -TrueType and Type\ 1 format. This family consists of the fonts +TrueType and Type\ 1 format. +This family consists of the fonts .Em Luxi Serif , with XLFD .Bd -literal @@ -648,7 +679,8 @@ Each of these fonts comes Roman, oblique, bold and bold oblique variants The TrueType version have glyphs covering the basic ASCII Unicode range, the Latin\ 1 range, as well as the .Em Extended Latin -range and some additional punctuation characters. In particular, +range and some additional punctuation characters. +In particular, these fonts include all the glyphs needed for ISO\ 8859 parts 1, 2, 3, 4, 9, 13 and 15, as well as all the glyphs in the Adobe Standard encoding and the Windows 3.1 character set. @@ -658,8 +690,10 @@ and only covers ISO\ 8859 parts 1, 2 and 15 as well as the Adobe Standard encoding. .Pp The Luxi fonts are original designs by Kris Holmes and Charles -Bigelow. Luxi fonts include seriffed, sans serif, and monospaced -styles, in roman and oblique, and normal and bold weights. The fonts +Bigelow. +Luxi fonts include seriffed, sans serif, and monospaced +styles, in roman and oblique, and normal and bold weights. +The fonts share stem weight, x-height, capital height, ascent and descent, for graphical harmony. .Pp @@ -720,7 +754,8 @@ Two of the scalable backends (Type\ 1 and the TrueType backend) use a common .Em fontenc layer for -font re-encoding. This allows these backends to share their encoding +font re-encoding. +This allows these backends to share their encoding data, and allows simple configuration of new locales independently of font type. .Pp @@ -734,7 +769,8 @@ In the layer, an encoding is defined by a name (such as .Ql iso8859-1 ) , possibly a number of aliases (alternate names), and -an ordered collection of mappings. A mapping defines the way the +an ordered collection of mappings. +A mapping defines the way the encoding can be mapped into one of the .Em target encodings known to @@ -747,7 +783,8 @@ A number of encodings are hardwired into .Em fontenc , and are therefore always available; the hardcoded encodings cannot easily be -redefined. These include: +redefined. +These include: .Bl -bullet .It .Ql iso10646-1 : @@ -827,14 +864,16 @@ file named .Pa encodings.dir . If found, this file is scanned for the requested encoding, and the relevant encoding definition file is -read in. The +read in. +The .Dq Nm mkfontdir utility, when invoked with the .Dq Li -e option followed by the name of a directory containing encoding files, can be used to automatically build .Pa encodings.dir -files. Please see the +files. +Please see the .Lk mkfontdir.1.html mkfontdir(1) manual page for more details. .Pp @@ -850,21 +889,26 @@ later in this document. .Sy The FreeType backend .Pp For TrueType and OpenType fonts, the FreeType backend scans the -mappings in order. Mappings with a target of PostScript are ignored; +mappings in order. +Mappings with a target of PostScript are ignored; mappings with a TrueType or Unicode target are checked against all the -cmaps in the file. The first applicable mapping is used. +cmaps in the file. +The first applicable mapping is used. .Pp For Type\ 1 fonts, the FreeType backend first searches for a -mapping with a target of PostScript. If one is found, it is used. +mapping with a target of PostScript. +If one is found, it is used. Otherwise, the backend searches for a mapping with target Unicode, which is then composed with a built-in table mapping codes to glyph -names. Note that this table only covers part of the Unicode code +names. +Note that this table only covers part of the Unicode code points that have been assigned names by Adobe. .Pp Specifying an encoding value of .Ql adobe-fontspecific for a -Type\ 1 font disables the encoding mechanism. This is useful with +Type\ 1 font disables the encoding mechanism. +This is useful with symbol and incorrectly encoded fonts (see .Sx Hints_about_using_badly_encoded_fonts below). @@ -890,8 +934,10 @@ file has a similar format to Its first line specifies the number of encodings, while every successive line has two columns, the name of the encoding, and the name of the encoding file; this can be relative to the current -directory, or absolute. Every encoding name should agree with the -encoding name defined in the encoding file. For example, +directory, or absolute. +Every encoding name should agree with the +encoding name defined in the encoding file. +For example, .Bd -literal 3 mulearabic-0 /usr/share/fonts/X11/encodings/mulearabic-0.enc @@ -905,7 +951,8 @@ be specified in the encoding file's .Dq Li STARTENCODING or .Dq Li ALIAS -line. It is not enough to create +line. +It is not enough to create an .Pa encodings.dir entry. @@ -917,7 +964,8 @@ The .Pa encoding.dir files are best maintained by the .Dq Nm mkfontdir -utility. Please see the +utility. +Please see the .Lk mkfontdir.1.html mkfontdir(1) manual page for more information. .Pp @@ -927,7 +975,8 @@ The encoding files are .Dq free form, .Em i.e. any string of -whitespace is equivalent to a single space. Keywords are parsed in a +whitespace is equivalent to a single space. +Keywords are parsed in a non-case-sensitive manner, meaning that .Dq Li size , .Dq Li SIZE , @@ -965,15 +1014,18 @@ an XLFD font name, and therefore contain exactly one dash .Dq Li - . .Pp The encoding file may then optionally declare the size of the -encoding. For a linear encoding (such as ISO\ 8859-1), the SIZE +encoding. +For a linear encoding (such as ISO\ 8859-1), the SIZE line specifies the maximum code plus one: .Bd -literal SIZE 0x2B .Ed .Pp -For a matrix encoding, it should specify two numbers. The first is +For a matrix encoding, it should specify two numbers. +The first is the number of the last row plus one, the other, the highest column -number plus one. In the case of +number plus one. +In the case of .Dq Li jisx0208.1990-0 (JIS\ X\ 0208(1990), double-byte encoding, high bit clear), it should be @@ -984,7 +1036,8 @@ SIZE 0x75 0x80 In the case of a matrix encoding, a .Dq Li FIRSTINDEX line may be -included to specify the minimum glyph index in an encoding. The +included to specify the minimum glyph index in an encoding. +The keyword .Dq Li FIRSTINDEX is followed by two integers, the minimum row @@ -996,7 +1049,8 @@ FIRSTINDEX 0x20 0x20 In the case of a linear encoding, a .Dq Li FIRSTINDEX line is not very -useful. If for some reason however you chose to include on, it should +useful. +If for some reason however you chose to include on, it should be followed by a single integer. .Pp Note that in most font backends inclusion of a @@ -1009,11 +1063,13 @@ Codes outside the region defined by the .Dq Li SIZE and .Dq Li FIRSTINDEX -lines are understood to be undefined. Encodings +lines are understood to be undefined. +Encodings default to linear encoding with a size of 256 (0x100). This means that you must declare the size of all 16 bit encodings. .Pp -What follows is one or more mapping sections. A mapping section +What follows is one or more mapping sections. +A mapping section starts with a .Dq Li STARTMAPPING line stating the target of the mapping. @@ -1038,7 +1094,8 @@ STARTMAPPING postscript .El .Pp Every line in a mapping section maps one from the encoding being -defined to the target of the mapping. In mappings with a Unicode or +defined to the target of the mapping. +In mappings with a Unicode or TrueType mapping, codes are mapped to codes: .Bd -literal 0x21 0x0660 @@ -1047,26 +1104,24 @@ TrueType mapping, codes are mapped to codes: .Ed .Pp As an abbreviation, it is possible to map a contiguous range of codes -in a single line. A line consisting of three integers +in a single line. +A line consisting of three integers .Bd -literal \[u003C]it/start/ \[u003C]it/end/ \[u003C]it/target/ .Ed .Pp is an abbreviation for the range of lines .Bd -literal -.Em start -.Em target +.Em start Em target .Ed .Bd -literal -.Em start Ns +1 -.Em target Ns +1 +.Em start Ns +1 Em target Ns +1 .Ed .Bd -literal \&... .Ed .Bd -literal -.Em end -.Em target Ns + Ns Em end Ns - Ns Em start +.Em end Em target Ns Pf + Em end Ns Pf - Em start .Ed .Pp For example, the line @@ -1098,7 +1153,8 @@ or, for a single code, UNDEFINE 0x1234 .Ed .Pp -PostScript mappings are different. Every line in a PostScript mapping +PostScript mappings are different. +Every line in a PostScript mapping maps a code to a glyph name .Bd -literal 0x41 A @@ -1137,7 +1193,8 @@ one of the .Ql microsoft-symbol and .Ql apple-roman -encodings. A +encodings. +A number of symbol fonts, however, are not marked as such; such fonts should be installed using .Ql microsoft-cp1252 , @@ -1146,7 +1203,8 @@ or, for older fonts, .Pp In order to guarantee consistent results (especially between Type\ 1 and TrueType versions of the same font), it is possible to -define a special encoding for a given font. This has already been done +define a special encoding for a given font. +This has already been done for the .Ql ZapfDingbats font; see the file @@ -1154,10 +1212,12 @@ font; see the file .Pp .Sy Hints about using badly encoded fonts .Pp -A number of text fonts are incorrectly encoded. Incorrect encoding +A number of text fonts are incorrectly encoded. +Incorrect encoding is sometimes done by design, in order to make a font for an exotic script appear like an ordinary Western text font on systems which are -not easily extended with new locale data. It is often the result of +not easily extended with new locale data. +It is often the result of the font designer's laziness or incompetence; for some reason, most people seem to find it easier to invent idiosyncratic glyph names rather than follow the Adobe glyph list. @@ -1173,7 +1233,8 @@ file. In the case of Type\ 1 fonts, the font designer can specify a default encoding; this encoding is requested by using the .Dq Li adobe-fontspecific -encoding in the XLFD name. Sometimes, the +encoding in the XLFD name. +Sometimes, the font designer omitted to specify a reasonable default encoding, in which case you should experiment with .Dq Li adobe-standard , @@ -1186,7 +1247,8 @@ and doesn't make sense for Type\ 1 fonts). .Pp -TrueType fonts do not have a default encoding. However, most TrueType +TrueType fonts do not have a default encoding. +However, most TrueType fonts are designed with either Microsoft or Apple platforms in mind, so one of .Dq Li microsoft-symbol , @@ -1200,7 +1262,8 @@ results. .Sy Specifying an ad hoc encoding file .Pp It is always possible to define an encoding file to put the glyphs -in a font in any desired order. Again, see the +in a font in any desired order. +Again, see the .Pa encodings/adobe-dingbats.enc file to see how this is done. .Pp @@ -1217,9 +1280,11 @@ remap them to their proper names. .Pp This is done by writing a .Pa fonts.alias -file. The format of this file +file. +The format of this file is very simple: it consists of a series of lines each mapping an alias -name to a font name. A +name to a font name. +A .Pa fonts.alias file might look as follows: .Bd -literal @@ -1267,7 +1332,8 @@ and .Pp In order to access the faces in a TrueType Collection file, the face number must be specified in the fonts.dir file before the filename, -within a pair of colons, or by setting the 'fn' TTCap option. For example, +within a pair of colons, or by setting the 'fn' TTCap option. +For example, .Bd -literal :1:mincho.ttc -misc-pmincho-medium-r-normal--0-0-0-0-p-0-jisx0208.1990-0 .Ed @@ -1291,7 +1357,8 @@ general syntax option=value: .Ed .Pp -and should be specified before the filename. The new +and should be specified before the filename. +The new .Em FreeType almost perfectly supports TTCap options that are compatible with X-TT 1.4. The Automatic Italic @@ -1315,7 +1382,8 @@ bw=0.5:ds=y:ai=0.2:mincho.ttc -misc-mincho-bold-i-normal--0-0-0-0-c-0-jisx0201.1 .Ed .Pp setup the complete combination of jisx0208 and jisx0201 using mincho.ttc -only. More information on the TTCap syntax is found on +only. +More information on the TTCap syntax is found on .Lk http://x-tt.sourceforge.jp/ "the After X-TT Project page" . .Pp The @@ -1335,20 +1403,24 @@ When loading a proportional fonts which contain a huge number of glyphs, the old .Em FreeType delayed glyph rasterisation until the time at which -the glyph was first used. The new FreeType (libfreetype-xtt2) has an +the glyph was first used. +The new FreeType (libfreetype-xtt2) has an improved .Dq very lazy metric calculation method to speed up the process when -loading TrueType or OpenType fonts. Although the +loading TrueType or OpenType fonts. +Although the .Em X-TT module also has this method, the .Pf \(dq Ql vl=y Ns \(dq TTCap option must be set if you want to -use it. This is the default method for +use it. +This is the default method for .Em FreeType when it loads -multi-byte fonts. Even if you use a unicode font which has tens of +multi-byte fonts. +Even if you use a unicode font which has tens of thousands of glyphs, this delay will not be worrisome as long as you use the new .Em FreeType @@ -1359,16 +1431,19 @@ method is super-fast. The maximum error of bitmap position using .Dq very lazy method is 1 pixel, -and is the same as that of a character-cell spacing. When the X-TT +and is the same as that of a character-cell spacing. +When the X-TT backend is used with the .Dq Li vl=y option, a chipped bitmap is displayed -with certain fonts. However, the new FreeType backend has minimal problem +with certain fonts. +However, the new FreeType backend has minimal problem with this, since it corrects left- and right-side bearings using .Dq italicAngle in the TrueType/OpenType post table, and does automatic correction of bitmap positions when rasterisation so that chipped bitmaps -are not displayed. Nevertheless if you don't want to use the +are not displayed. +Nevertheless if you don't want to use the .Dq very lazy method when using multi-bytes fonts, set .Dq Li vl=n @@ -1393,7 +1468,8 @@ fs=c:mincho.ttc -misc-mincho-medium-r-normal--0-0-0-0-p-0-jisx0208.1990-0 .Ed .Pp will not compute the metric for each glyph, but instead -trust the font to be a character-cell font. You are +trust the font to be a character-cell font. +You are encouraged to make use of this optimisation when useful, but be warned that not all monospaced fonts are character-cell fonts. .Sh APPENDIX: BACKGROUND AND TERMINOLOGY @@ -1401,23 +1477,27 @@ that not all monospaced fonts are character-cell fonts. A computer text-processing system inputs keystrokes and outputs .Em glyphs , small pictures that are assembled on paper or on a -computer screen. Keystrokes and glyphs do not, in general, coincide: +computer screen. +Keystrokes and glyphs do not, in general, coincide: for example, if the system does generate ligatures, then to the sequence of two keystrokes .Pf < Ql f Ns > Ns < Ns Ql i Ns > will typically -correspond a single glyph. Similarly, if the system shapes Arabic +correspond a single glyph. +Similarly, if the system shapes Arabic glyphs in a vaguely reasonable manner, then multiple different glyphs may correspond to a single keystroke. .Pp The complex transformation rules from keystrokes to glyphs are usually factored into two simpler transformations, from keystrokes to .Em characters -and from characters to glyphs. You may want to think +and from characters to glyphs. +You may want to think of characters as the basic unit of text that is stored .Em e.g. in -the buffer of your text editor. While the definition of a character +the buffer of your text editor. +While the definition of a character is intrinsically application-specific, a number of standardised collections of characters have been defined. .Pp @@ -1427,7 +1507,8 @@ is a set of characters together with a mapping from integer codes --- known as .Em codepoints --- to -characters. Examples of coded character sets include US-ASCII, +characters. +Examples of coded character sets include US-ASCII, ISO\ 8859-1, KOI8-R, and JIS\ X\ 0208(1990). .Pp A coded character set need not use 8 bit integers to index characters. @@ -1465,8 +1546,10 @@ or and .Em OpenType . .Pp -The glyph data in a digital font needs to be indexed somehow. How -this is done depends on the font file format. In the case of +The glyph data in a digital font needs to be indexed somehow. +How +this is done depends on the font file format. +In the case of Type\ 1 fonts, glyphs are identified by .Em glyph names . In the @@ -1501,11 +1584,14 @@ of some fields: -adobe-courier-medium-r-normal--0-0-0-0-m-0-iso8859-1 .Ed .Pp -X11 font instances may also be specified by short name. Unlike an +X11 font instances may also be specified by short name. +Unlike an XLFD, a short name has no structure and is simply a conventional name -for a font instance. Two short names are of particular interest, as +for a font instance. +Two short names are of particular interest, as the server will not start if font instances with these names cannot be -opened. These are +opened. +These are .Dq Li fixed , which specifies the fallback font to use when the requested font cannot be opened, and @@ -1527,7 +1613,8 @@ Unicode .Pf ( Lk http://www.unicode.org http://www.unicode.org ) is a coded character set with the goal of uniquely identifying all characters for all -scripts, current and historical. While Unicode was explicitly not +scripts, current and historical. +While Unicode was explicitly not designed as a glyph encoding scheme, it is often possible to use it as such. .Pp @@ -1542,7 +1629,8 @@ meaning that it only defines glyphs for a subset of the character registry of Unicode. .Pp The Unicode standard is defined in parallel with the international -standard ISO\ 10646. Assignments in the two standards are always +standard ISO\ 10646. +Assignments in the two standards are always equivalent, and we often use the terms .Em Unicode and @@ -1554,7 +1642,8 @@ have the last two fields of their XLFD set to .Dq Li iso10646-1 . .Sh REFERENCES X11R6 comes with extensive documentation in the form of manual -pages and typeset documents. Before installing fonts, you really should +pages and typeset documents. +Before installing fonts, you really should read the .Lk fontconfig.3.html fontconfig(3) and |