projects / unix-history / blame
| Commit | Line | Data |
|---|---|---|
| 15637ed4 RG |
1 | .\" Contributed to 386bsd 0.1 and later versions |
| 2 | .\" | |
| 3 | .\" Copyright 1992 by Holger Veit | |
| 4 | .\" May be freely used with Bill Jolitz's port of | |
| 5 | .\" 386bsd and may be included in a 386bsd collection | |
| 6 | .\" as long as binary and source are available and reproduce the above | |
| 7 | .\" copyright. | |
| 8 | .\" | |
| 9 | .\" You may freely modify this code and contribute improvements based | |
| 10 | .\" on this code as long as you don't claim to be the original author. | |
| 11 | .\" Commercial use of this source requires permittance of the copyright | |
| 12 | .\" holder. A general license for 386bsd will override this restriction. | |
| 13 | .\" | |
| 14 | .\" Use at your own risk. The copyright holder or any person who makes | |
| 15 | .\" this code available for the public (administrators of public archives | |
| 16 | .\" for instance) are not responsible for any harm to hardware or software | |
| 17 | .\" that might happen due to wrong application or program faults. | |
| 18 | .\" | |
| 19 | .\" You must have the codriver driver in the same package generated | |
| 20 | .\" into the 386bsd kernel, otherwise this program does not work. | |
| 21 | .\" | |
| 22 | .\" @(#)vgafont.5 1.0 (contributed to 386bsd) 10/25/92 | |
| 23 | .\" | |
| 24 | .Dd October 25, 1992 | |
| 25 | .Dt CONSOLE 5 | |
| 26 | .Os | |
| 27 | .Sh NAME | |
| 28 | .Nm vgafont | |
| 29 | .Nd setfont bdf font format | |
| 30 | .Sh DESCRIPTION | |
| 31 | This document describes the differences between the font format loadable by | |
| 32 | the | |
| 33 | .Xr setfont 3 | |
| 34 | routine and the original bdf (bitmap distribution format) as used by | |
| 35 | the X11 Windows System Release 5. | |
| 36 | .Pp | |
| 37 | In general, | |
| 38 | .Fn setfont | |
| 39 | understands all keywords of the bdf file, but only uses a subset of them. | |
| 40 | .Pp | |
| 41 | The main restriction for usability of fonts is that the console is | |
| 42 | operated in text mode whereas the X11 Windows system uses | |
| 43 | graphics to display a character. Thus, a usable | |
| 44 | font underlies the following limits: | |
| 45 | .Pp | |
| 46 | .Bl -enum -compact | |
| 47 | .It | |
| 48 | The bitmap of a character must be smaller than 8x16. Note that this fits for | |
| 49 | a 3x5 font for instance; it is, however, not recommended to load such small | |
| 50 | fonts, because this font is displayed in a 8x16 pixel map anyway, and thus | |
| 51 | might look quite funny. | |
| 52 | .It | |
| 53 | The font should have fixed width, however, proportional fonts may be | |
| 54 | loaded into the fixed grid, but look quite ugly then. | |
| 55 | .It | |
| 56 | A character set may contain a maximum of 256 entries. Together with the | |
| 57 | facility of the console driver to load two fonts, there may be 512 different | |
| 58 | characters displayed simultaneously. This is sufficient for most | |
| 59 | latin character sets (if you want to do word processing or TeX, use a | |
| 60 | graphical video system). | |
| 61 | .It | |
| 62 | X11 uses a 16 bit encoding scheme similiar to the ISO 10646-1 Draft standard | |
| 63 | to express a character code. 386bsd is currently based on a 8 bit scheme. | |
| 64 | To allow more than 256 character codes and retaining 8 bit compatibility, | |
| 65 | the console driver uses a pair of special codes to switch between fonts. | |
| 66 | The code | |
| 67 | .Em 0x0e (SO) | |
| 68 | enables the second font, the code | |
| 69 | .Em 0x0f (SI) | |
| 70 | switches back to the first (default) font. If no second font is loaded, | |
| 71 | SI and SO are ignored. | |
| 72 | .Pp | |
| 73 | This handling of fonts and encoding is experimental, and may be modified | |
| 74 | in the future, if a better scheme (UniCode, or ISO-DIS 10646 1.2) is | |
| 75 | available and standardized. | |
| 76 | .Pp | |
| 77 | .Sh EXAMPLE | |
| 78 | The following is a sample bdf font skeleton which is accepted by | |
| 79 | .Fn setfont . | |
| 80 | It should not be misunderstood as an official description of the bdf font | |
| 81 | format. | |
| 82 | .Pp | |
| 83 | .Bd -literal | |
| 84 | COMMENT This is a comment and may occur anywhere | |
| 85 | STARTFONT 2.1 ignored | |
| 86 | FONT vga ignored | |
| 87 | SIZE 16 75 75 first number used as box length | |
| 88 | FONTBOUNDINGBOX 8 16 0 -4 first two numbers used as box size | |
| 89 | STARTPROPERTIES 3 ignored | |
| 90 | FONT_DESCENT 4 ignored | |
| 91 | FONT_ASCENT 12 ignored | |
| 92 | DEFAULT_CHAR 0 used to fill empty slots | |
| 93 | ENDPROPERTIES used | |
| 94 | CHARS 256 used | |
| 95 | STARTCHAR C0000 ignored | |
| 96 | ENCODING 0 used | |
| 97 | SWIDTH 666 0 ignored | |
| 98 | DWIDTH 8 0 ignored | |
| 99 | BBX 8 16 0 -4 used | |
| 100 | BITMAP used | |
| 101 | 00 bitmap must fit length and width | |
| 102 | 00 | |
| 103 | 00 | |
| 104 | 7c | |
| 105 | c6 | |
| 106 | c6 | |
| 107 | de | |
| 108 | de | |
| 109 | de | |
| 110 | dc | |
| 111 | c0 | |
| 112 | 7c | |
| 113 | 00 | |
| 114 | 00 | |
| 115 | 00 | |
| 116 | 00 | |
| 117 | ENDCHAR used | |
| 118 | ... Startchar-Endchar repeated | |
| 119 | ENDFONT used | |
| 120 | .Ed | |
| 121 | .Pp | |
| 122 | .Sh Files | |
| 123 | .Bl -tag -width *.bdf -compact | |
| 124 | .It Pa *.bdf | |
| 125 | bdf font file | |
| 126 | .El | |
| 127 | .Sh SEE ALSO | |
| 128 | .Xr co 4 , | |
| 129 | .Xr keycap 5 | |
| 130 | .Sh HISTORY | |
| 131 | The bdf font format is part of the MIT X11 distribution. | |
| 132 | .Sh BUGS | |
| 133 | The problem of languages writing right-to-left is not yet handled. Currently, | |
| 134 | words in such a language must be prepared as an inverse character string. |