1SFDDIFF(1) General Commands Manual SFDDIFF(1)
2
3
4
6 sfddiff - compare two font files
7
9 sfddiff [--help] [--ignorehints] [--ignorenames] [--ignoregpos]
10 [--ignoregsub] [--ignorebitmaps] [--exact] [--warn] [--merge outfile]
11 [--usage] [--version] fontfile1 fontfile2
12
14 The program sfddiff compares two font files, which may be in any format
15 that fontforge(1) can read. It will notice the following differences:
16
17 1) Characters are present in one font but not in the other.
18
19 2) Characters are present in both fonts but have different sets of
20 outlines or references. The outlines may be compared so that only
21 exact matches are accepted, or so that a fuzzier match is used.
22 Similarly references may need to match exactly, or may be matched
23 after an unlink. This fuzzy comparison is useful when comparing
24 truetype and postscript fonts, or when comparing a font with refer‐
25 ences to one without.
26
27 3) The PostScript hints or TrueType instructions are different.
28
29 4) The font names (the TrueType 'name' tables) differ.
30
31 5) The kerning (and other 'gpos' information) differs.
32
33 6) The ligatures (and other 'gsub' information) differ.
34
35 7) Any bitmap strikes present in one font but not in the other.
36
37 8) Any bitmap characters present in one strike of one font but not in
38 the equivalent strike of the other.
39
40 9) Any bitmap characters which differ.
41
43 --help Provide a description with a list of the available
44 options.
45
46 --ignorehints Suppress the reporting of hint/instruction differences.
47
48 --ignoregpos Suppress the reporting of kerning (and other 'gpos')
49 differences.
50
51 --ignoregsub Suppress the reporting of ligature (and other 'gsub')
52 differences.
53
54 --ignorenames Suppress the reporting of name string differences.
55
56 --ignorebitmaps Suppress the reporting of bitmap differences.
57
58 --exact Require outlines to match exactly.
59
60 --warn Warn if the outlines/references are slightly different.
61
62 --merge outfile Store a merged version of the two fonts into the speci‐
63 fied output file. The merged data will be based on
64 sfdfile1, any characters present in sfdfile2 but not in
65 sfdfile1 will be added, and the outlines of sfdfile2
66 will be placed in the background. Finally, for any
67 characters with different outlines or references the
68 background of the character will contain the outlines
69 from sfdfile2 (references will be unlinked into out‐
70 lines and those outlines also will be added).
71
72 --usage Display the usage description.
73
74 --version Display the current version.
75
77 fontforge(1)
78
79 The HTML version of the FontForge manual, available online at:
80 http://fontforge.sourceforge.net/.
81
83 FontForge used to be called PfaEdit.
84
86 FontForge is Copyright © 2000–2014 by George Williams, and is currently
87 maintained by the FontForge development team. See /usr/share/doc/font‐
88 forge/AUTHORS for a comprehensive list of contributors.
89
91 The sfddiff program is licensed under GPLv3+: GNU GPL version 3 or
92 later (http://gnu.org/licenses/gpl.html) with many parts covered by a
93 BSD license (http://fontforge.org/license.html). Please read the
94 LICENSE file included in the FontForge distribution for details, or see
95 https://github.com/fontforge/fontforge/blob/master/LICENSE.
96
97 FontForge is available as a whole under the terms of the GNU GPL
98 (http://www.gnu.org/copyleft/gpl.html), version 3 or any later version.
99 However, almost all of its parts are available under the "revised BSD
100 license" (http://www.law.yi.org/~sfllaw/talks/bsd.pdf) because Font‐
101 Forge was mostly written by George Williams, using that license.
102
103 The Revised BSD License is very permissive, and allows for code to be
104 combined with other code under other licenses.
105
106 There are many useful libraries available under copyleft libre
107 licenses, such as the LGPL and GPL, which FontForge started to use in
108 2012.
109
110 For example, Pango and Cairo are available under the LGPL.
111
112 Some features added since 2012 are licensed by their individual devel‐
113 opers under the GPLv3.
114
116 See the FontForge Github Issue Tracker, at https://github.com/font‐
117 forge/fontforge/issues/.
118
119
120
121 2017 Jun 18 SFDDIFF(1)