.TH JF 9.1
.CT 1 editor graphics
.SH NAME
jf \- font editor
.SH SYNOPSIS
.B jf
[
.I file ...
]
.SH DESCRIPTION
.I Jf
edits jerq font files.
If
.I file
does not begin with a slash and is not a font file,
it is looked up in a standard font directory.
.PP
.I Jf
is mostly mouse- and
menu-driven, except when prompting for file names.
.I Jf
divides its layer into two types of areas:
Font displays
show all characters in a given font in actual size.
When characters are opened for editing, they appear magnified in
edit displays.
.PP
Button 1
is the `do it' button.
Clicking button 1 inside a font display
opens a character for editing; inside an edit display
it sets a pixel.
It may have other functions selected via menus, in which case the function
is indicated by a special cursor.
.PP
Button 2
is the `undo it' button.
Clicking button 2 closes a character or clears a
pixel, unless conditioned otherwise via menu selection.
.PP
Button 3
is the `menu' button.
Clicking button 3 selects a menu, pops control
back to the top level, or (when the gunsight cursor shows)
picks a font or character to be affected.
Sometimes menu selection is the only (non-trivial)
option available, as indicated by a `menu' cursor.
.PP
A font is described by several parameters; these are either read from the
font file, or set by default by the
.B make new font
function:
.B max width
(default 16 pixels),
.B height
(16)\-measured from the top,
.B ascent
(16)\-the distance of the printing baseline from the top, and
.B range
(1)\-the highest-numbered character in the font.
(The first character is numbered 0.)
All may be changed under the
.B set sizes
menu.
.B Squeeze font,
in the
.B open/close font
menu, reduces max width as much as possible.
.PP
Each character has a width, which is shown by the length of the baseline
in the edit display.
The
.B char width
may be set under the
.B set sizes
menu; button 1 sets it to 0, button 2 sets it to a specified pixel
within the max width.
The quantity
.B char left
may be used for kerning.
If positive, it shifts a character right and causes
.B max width
to increase if necessary; if negative, the character will be shifted
left.
Otherwise
.I char left
is irrelevant to font editing.
.PP
The
.B bit function
menu controls copying among characters in any of the
.IR bitblt (9.3)
Codes:
.BR F_STORE ,
.BR F_CLR ,
.BR F_OR ,
.BR F_XOR.
Press button 3 on the source character; hold it down while moving and
release it on the destination.
.PP
Several fonts may be open at once.
When editing a font, it is often convenient to open a second copy
for recovering botched characters.
.SH FILES
.TF /usr/jerq/include/font.h
.TP
.F /usr/jerq/font/*
jerq fonts
.TP
.F /usr/jerq/include/font.h
jerq font header file
.SH SEE ALSO
.IR font (9.5)
.SH DIAGNOSTICS
When out of memory or screen area, 
.I jf
ignores the offending operation.