1 .TH FACE 7
2 .SH NAME
3 face \- face files
4 .SH DESCRIPTION
5 The directories
6 .B /usr/$user/lib/face
7 and
8 .B /lib/face
9 contain a hierarchy of images of people.
10 In those directories are subdirectories named by the sizes of
11 the corresponding image files:
12 .B 48x48x1
13 (48 by 48 pixels, one bit per pixel);
14 .B 48x48x2
15 (48 by 48 pixels, two (grey) bits per pixel);
16 .B 48x48x4
17 (48 by 48 pixels, four (grey) bits per pixel);
18 .B 48x48x8
19 (48 by 48 pixels, eight (color-mapped) bits per pixel);
20 .B 512x512x8
21 (512 by 512 pixels, eight (color-mapped) bits per pixel);
22 .B 512x512x24
23 (512 by 512 pixels, twenty-four bits per pixel (3 times 8 bits
24 per color)).
25 The large files serve no special purpose; they are stored
26 as images
27 (see
28 .MR image (7) ).
29 The small files are the `icons'  displayed by
30 .B faces
31 and
32 .B seemail
33 (see Plan 9's
34 .IR faces (1));
35 for depths less than 4, their format is special.
36 .PP
37 One- and two-bit deep icons are stored as text, one line of the file to one scan line
38 of display.
39 Each line is divided into 8-bit, 16-bit, or 32-bit big-endian words,
40 stored as a list of comma-separated hexadecimal C constants,
41 such as:
42 .IP
43 .EX
44 0x9200, 0x1bb0, 0x003e,
45 .EE
46 .PP
47 This odd format is historical and the programs that read it
48 are somewhat forgiving about blanks and the need for commas.
49 .PP
50 The files
51 .BR  lib/face/*/.dict
52 hold a correspondence between users at machines
53 and face files.
54 The format is
55 .IP
56 .EX
57 .I machine\fB/\fPuser directory\fB/\fPfile\fB.\fPver
58 .EE
59 .PP
60 The
61 .I machine
62 is the domain name of the machine sending the message,
63 and
64 .I user
65 the name of the user sending it.
66 The
67 .I directory
68 is a further subdirectory of (say)
69 .BR /lib/face/48x48x1 ,
70 named by a single letter corresponding to the first character
71 of the user names.  The
72 .I file
73 is the name of the file, typically but not always the user name,
74 and
75 .I ver
76 is a number to distinguish different images, for example to
77 distinguish the image for Bill Gates from the image for Bill Joy,
78 both of which might otherwise be called
79 .BR b/bill .
80 For example, Bill Gates might be represented by the line
81 .IP
82 .EX
83 microsoft.com/bill b/bill.1
84 .EE
85 .PP
86 If multiple entries exist for a user in the various
87 .B .dict
88 files,
89 .I faces
90 chooses the highest pixel size less than or equal to that of the
91 display on which it is running.
92 .PP
93 Finally, or rather firstly, the file
94 .B /lib/face/.machinelist
95 contains a list of machine/domain pairs, one per line,
96 to map any of a set of machines to a single domain name to
97 be looked up in the
98 .B .dict
99 files.  The machine name may be a regular expression,
100 so for example the entry
101 .IP
102 .EX
103 \&.*research\e.bell-labs\e.com    astro
104 .EE
105 .PP
106 maps any of the machines in Bell Labs Research into the
107 shorthand name
108 .BR astro ,
109 which then appears as a domain name in the
110 .B .dict
111 files.
112 .SH "SEE ALSO"
113 .MR mail (1) ,
114 .MR tweak (1) ,
115 .MR image (7)