VFONT

Section: File Formats (5)
Updated: May 13, 1986
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NAME

vfont - font formats for the Benson-Varian or Versatec

SYNOPSIS

/usr/lib/vfont/*

DESCRIPTION

The fonts for the printer/plotters have the following format. Each file contains a header, an array of 256 character description structures, and then the bit maps for the characters themselves. The header has the following format:


struct header {
        short           magic;
        unsigned short  size;
        short           maxx;
        short           maxy;
        short           xtnd;
} header;

The magic number is 0436 (octal). The maxx, maxy, and xtnd fields are not used at the current time. Maxx and maxy are intended to be the maximum horizontal and vertical size of any glyph in the font, in raster lines. The size is the size of the bit maps for the characters in bytes. Before the maps for the characters is an array of 256 structures for each of the possible characters in the font. Each element of the array has the form:


struct dispatch {
        unsigned short  addr;
        short           nbytes;
        char            up;
        char            down;
        char            left;
        char            right;
        short           width;
};

The nbytes field is nonzero for characters which actually exist. For such characters, the addr field is an offset into the rest of the file where the data for that character begins. There are up+down rows of data for each character, each of which has left+right bits, rounded up to a number of bytes. The width field is not used by vcat, although it is to make width tables for troff. It represents the logical width of the glyph, in raster lines, and shows where the base point of the next glyph would be.

FILES