groff_font.man revision 18099
1114402Sru.ig \"-*- nroff -*- 2114402SruCopyright (C) 1989-1995 Free Software Foundation, Inc. 3114402Sru 4114402SruPermission is granted to make and distribute verbatim copies of 5114402Sruthis manual provided the copyright notice and this permission notice 6114402Sruare preserved on all copies. 7114402Sru 8114402SruPermission is granted to copy and distribute modified versions of this 9114402Srumanual under the conditions for verbatim copying, provided that the 10114402Sruentire resulting derived work is distributed under the terms of a 11114402Srupermission notice identical to this one. 12114402Sru 13114402SruPermission is granted to copy and distribute translations of this 14114402Srumanual into another language, under the above conditions for modified 15114402Sruversions, except that this permission notice may be included in 16114402Srutranslations approved by the Free Software Foundation instead of in 17114402Sruthe original English. 18114402Sru.. 19114402Sru.de TQ 20114402Sru.br 21114402Sru.ns 22114402Sru.TP \\$1 23114402Sru.. 24114402Sru.\" Like TP, but if specified indent is more than half 25114402Sru.\" the current line-length - indent, use the default indent. 26114402Sru.de Tp 27114402Sru.ie \\n(.$=0:((0\\$1)*2u>(\\n(.lu-\\n(.iu)) .TP 28114402Sru.el .TP "\\$1" 29114402Sru.. 30114402Sru.TH GROFF_FONT @MAN5EXT@ "@MDATE@" "Groff Version @VERSION@" 31114402Sru.SH NAME 32114402Srugroff_font \- format of groff device and font description files 33114402Sru.SH DESCRIPTION 34114402SruThe groff font format is roughly a superset of the ditroff 35114402Srufont format. 36114402SruUnlike the ditroff font format, there is no associated binary 37114402Sruformat. 38114402SruThe font files for device 39114402Sru.I name 40114402Sruare stored in a directory 41114402Sru.BI dev name. 42114402SruThere are two types of file: a 43114402Srudevice description file called 44114402Sru.B DESC 45114402Sruand for each font 46114402Sru.I F 47114402Srua font file called 48114402Sru.IR F . 49114402SruThese are text files; 50114402Sruthere is no associated binary format. 51114402Sru.SS DESC file format 52114402SruThe DESC file can contain the following types of line: 53114402Sru.TP 54114402Sru.BI res\ n 55114402SruThere are 56114402Sru.I n 57114402Srumachine units per inch. 58114402Sru.TP 59114402Sru.BI hor\ n 60114402SruThe horizontal resolution is 61114402Sru.I n 62114402Srumachine units. 63114402Sru.TP 64114402Sru.BI vert\ n 65114402SruThe vertical resolution is 66114402Sru.I n 67114402Srumachine units. 68114402Sru.TP 69114402Sru.BI sizescale\ n 70114402SruThe scale factor for pointsizes. 71114402SruBy default this has a value of 1. 72114402SruOne 73114402Sru.I 74114402Sruscaled point 75114402Sruis equal to 76114402Sruone 77114402Sru.RI point/ n . 78114402SruThe arguments to the 79114402Sru.B unitwidth 80114402Sruand 81114402Sru.B sizes 82114402Srucommands are given in scaled points. 83114402Sru.TP 84114402Sru.BI unitwidth\ n 85114402SruQuantities in the font files are given in machine units 86114402Srufor fonts whose point size is 87114402Sru.I n 88114402Sruscaled points. 89114402Sru.TP 90114402Sru.B tcommand 91114402SruThis means that the postprocessor can handle the 92114402Sru.B t 93114402Sruand 94114402Sru.B u 95114402Sruoutput commands. 96114402Sru.TP 97114402Sru.BI sizes\ s1\ s2\|.\|.\|.\|sn\ 0 98114402SruThis means that the device has fonts at 99114402Sru.IR s1 , 100114402Sru.IR s2 ,\|.\|.\|.\| sn 101114402Sruscaled points. 102114402SruThe list of sizes must be terminated by a 103114402Sru.BR 0 . 104114402SruEach 105114402Sru.BI s i 106114402Srucan also be a range of sizes 107114402Sru.IR m \- n . 108The list can extend over more than one line. 109.TP 110.BI styles\ S1\ S2\|.\|.\|.\|Sm 111The first 112.I m 113font positions will be associated with styles 114.IR S1\|.\|.\|.\|Sm . 115.TP 116.BI fonts\ n\ F1\ F2\ F3\|.\|.\|.\|Fn 117Fonts 118.I F1\|.\|.\|.\|Fn 119will be mounted in the font positions 120.IR m +1,\|.\|.\|., m + n 121where 122.I m 123is the number of styles. 124This command may extend over more than one line. 125A font name of 126.B 0 127will cause no font to be mounted on the corresponding font position. 128.TP 129.BI family\ fam 130The default font family is 131.IR fam . 132.TP 133.B charset 134This line and everything following in the file are ignored. 135It is allowed for the sake of backwards compatibility. 136.LP 137The res, unitwidth, fonts and sizes lines are compulsory. 138Other commands are ignored by 139.B troff 140but may be used by postprocessors to store arbitrary information 141about the device in the DESC file. 142.SS Font file format 143A font file has two sections. The first section is a sequence 144of lines each containing a sequence of blank delimited 145words; the first word in the line is a key, and subsequent 146words give a value for that key. 147.TP 148.BI name\ F 149The name of the font is 150.IR F . 151.TP 152.BI spacewidth\ n 153The normal width of a space is 154.IR n . 155.TP 156.BI slant\ n 157The characters of the font have a slant of 158.I n 159degrees. (Positive means forward.) 160.TP 161.BI ligatures\ lig1\ lig2\|.\|.\|.\|lign\ \fR[ 0 \fR] 162Characters 163.IR lig1 , 164.IR lig2 ,\|.\|.\|., lign 165are ligatures; possible ligatures are 166.BR ff , 167.BR fi , 168.BR fl 169and 170.BR ffl . 171For backwards compatibility, the list of ligatures may be terminated 172with a 173.BR 0. 174The list of ligatures may not extend over more than one line. 175.TP 176.B special 177The font is 178.IR special ; 179this means that when a character is requested that is not present in 180the current font, it will be searched for in any special fonts that 181are mounted. 182.LP 183Other commands are ignored by 184.B troff 185but may be used by postprocessors to store arbitrary information 186about the font in the font file. 187.LP 188The first section can contain comments which start with the 189.B # 190character and extend to the end of a line. 191.LP 192The second section contains one or two subsections. 193It must contain a 194.I charset 195subsection 196and it may also contain a 197.I kernpairs 198subsection. 199These subsections can appear in any order. 200Each subsection starts with a word on a line by itself. 201.LP 202The word 203.B charset 204starts the charset subsection. 205The 206.B charset 207line is followed by a sequence of lines. 208Each line gives information for one character. 209A line comprises a number of fields separated 210by blanks or tabs. The format is 211.IP 212.I 213name metrics type code comment 214.LP 215.I name 216identifies the character: 217if 218.I name 219is a single character 220.I c 221then it corresponds to the groff input character 222.IR c ; 223if it is of the form 224.BI \e c 225where c is a single character, then it 226corresponds to the groff input character 227.BI \e c\fR; 228otherwise it corresponds to the groff input character 229.BI \e[ name ] 230(if it is exactly two characters 231.I xx 232it can be entered as 233.BI \e( xx\fR.) 234Groff supports eight bit characters; however some utilities 235has difficulties with eight bit characters. 236For this reason, there is a convention that the name 237.BI char n 238is equivalent to the single character whose code is 239.I n . 240For example, 241.B char163 242would be equivalent to the character with code 163 243which is the pounds sterling sign in ISO Latin-1. 244The name 245.B \-\-\- 246is special and indicates that the character is unnamed; 247such characters can only be used by means of the 248.B \eN 249escape sequence in 250.BR troff . 251.LP 252The 253.I type 254field gives the character type: 255.TP 2561 257means the character has an descender, for example, p; 258.TP 2592 260means the character has an ascender, for example, b; 261.TP 2623 263means the character has both an ascender and a descender, for example, 264(. 265.LP 266The 267.I code 268field gives the code which the postprocessor uses to print the character. 269The character can also be input to groff using this code by means of the 270.B \eN 271escape sequence. 272The code can be any integer. 273If it starts with a 274.B 0 275it will be interpreted as octal; 276if it starts with 277.B 0x 278or 279.B 0X 280it will be intepreted as hexadecimal. 281.LP 282Anything on the line after the code field will be ignored. 283.LP 284The 285.I metrics 286field has the form: 287.IP 288.IR width [\fB, height [\fB, depth [\fB, italic_correction [\fB, \ 289left_italic_correction [\fB, subscript_correction ]]]]] 290.LP 291There must not be any spaces between these subfields. 292Missing subfields are assumed to be 0. 293The subfields are all decimal integers. 294Since there is no associated binary format, these 295values are not required to fit into a variable of type 296.B char 297as they are in ditroff. 298The 299.I width 300subfields gives the width of the character. 301The 302.I height 303subfield gives the height of the character (upwards is positive); 304if a character does not extend above the baseline, it should be 305given a zero height, rather than a negative height. 306The 307.I depth 308subfield gives the depth of the character, that is, the distance 309below the lowest point below the baseline to which the 310character extends (downwards is positive); 311if a character does not extend below above the baseline, it should be 312given a zero depth, rather than a negative depth. 313The 314.I italic_correction 315subfield gives the amount of space that should be added after the 316character when it is immediately to be followed by a character 317from a roman font. 318The 319.I left_italic_correction 320subfield gives the amount of space that should be added before the 321character when it is immediately to be preceded by a character 322from a roman font. 323The 324.I subscript_correction 325gives the amount of space that should be added after a character 326before adding a subscript. 327This should be less than the italic correction. 328.LP 329A line in the charset section can also have the format 330.IP 331.I 332name \fB" 333.LP 334This indicates that 335.I name 336is just another name for the character mentioned in the 337preceding line. 338.LP 339The word 340.B kernpairs 341starts the kernpairs section. 342This contains a sequence of lines of the form: 343.IP 344.I 345c1 c2 n 346.LP 347This means that when character 348.I c1 349appears next to character 350.I c2 351the space between them should be increased by 352.IR n . 353Most entries in kernpairs section will have a negative value for 354.IR n . 355.SH FILES 356.Tp \w'@FONTDIR@/devname/DESC'u+3n 357.BI @FONTDIR@/dev name /DESC 358Device description file for device 359.IR name . 360.TP 361.BI @FONTDIR@/dev name / F 362Font file for font 363.I F 364of device 365.IR name . 366.SH "SEE ALSO" 367.BR groff_out (@MAN5EXT@), 368.BR @g@troff (@MAN1EXT@). 369