Tribblix: manual page: sfddiff.1

SFDDIFF(1) User Commands SFDDIFF(1)

NAME

sfddiff - compare two font files

SYNOPSIS

sfddiff [--help] [--ignorehints] [--ignorenames] [--ignoregpos]
[--ignoregsub] [--ignorebitmaps] [--exact] [--warn] [--merge outfile]
[--usage] [--version] fontfile1 fontfile2

DESCRIPTION

The program sfddiff compares two font files, which may be in any
format that fontforge(1) can read. It will notice the following
differences:

1) Characters are present in one font but not in the other.

2) Characters are present in both fonts but have different sets of
outlines or references. The outlines may be compared so that only
exact matches are accepted, or so that a fuzzier match is used.
Similarly references may need to match exactly, or may be matched
after an unlink. This fuzzy comparison is useful when comparing
truetype and postscript fonts, or when comparing a font with
references to one without.

3) The PostScript hints or TrueType instructions are different.

4) The font names (the TrueType 'name' tables) differ.

5) The kerning (and other 'gpos' information) differs.

6) The ligatures (and other 'gsub' information) differ.

7) Any bitmap strikes present in one font but not in the other.

8) Any bitmap characters present in one strike of one font but not
in the equivalent strike of the other.

9) Any bitmap characters which differ.

OPTIONS

--help Provide a description with a list of the available
options.

--ignorehints Suppress the reporting of hint/instruction
differences.

--ignoregpos Suppress the reporting of kerning (and other 'gpos')
differences.

--ignoregsub Suppress the reporting of ligature (and other 'gsub')
differences.

--ignorenames Suppress the reporting of name string differences.

--ignorebitmaps Suppress the reporting of bitmap differences.

--exact Require outlines to match exactly.

--warn Warn if the outlines/references are slightly
different.

--merge outfile Store a merged version of the two fonts into the
specified output file. The merged data will be based
on sfdfile1, any characters present in sfdfile2 but
not in sfdfile1 will be added, and the outlines of
sfdfile2 will be placed in the background. Finally,
for any characters with different outlines or
references the background of the character will
contain the outlines from sfdfile2 (references will
be unlinked into outlines and those outlines also
will be added).

--usage Display the usage description.

--version Display the current version.

NOTE

FontForge used to be called PfaEdit.

AUTHORS

FontForge is Copyright (C) 2000-2014 by George Williams, and is
currently maintained by the FontForge development team. See
/usr/share/doc/fontforge/AUTHORS for a comprehensive list of
contributors.

LICENSE

The sfddiff program is licensed under GPLv3+: GNU GPL version 3 or
later (http://gnu.org/licenses/gpl.html) with many parts covered by a
BSD license (http://fontforge.org/license.html). Please read the
LICENSE file included in the FontForge distribution for details, or
see https://github.com/fontforge/fontforge/blob/master/LICENSE.

FontForge is available as a whole under the terms of the GNU GPL
(http://www.gnu.org/copyleft/gpl.html), version 3 or any later
version. However, almost all of its parts are available under the
"revised BSD license" (http://www.law.yi.org/~sfllaw/talks/bsd.pdf)
because FontForge was mostly written by George Williams, using that
license.

The Revised BSD License is very permissive, and allows for code to be
combined with other code under other licenses.

There are many useful libraries available under copyleft libre
licenses, such as the LGPL and GPL, which FontForge started to use in
2012.

For example, Pango and Cairo are available under the LGPL.

Some features added since 2012 are licensed by their individual
developers under the GPLv3.

BUGS

See the FontForge Github Issue Tracker, at
https://github.com/fontforge/fontforge/issues/.

2017 Jun 18 SFDDIFF(1)