1#! /bin/sh
2#
3# grap2graph -- compile graph description descriptions to bitmap images
4#
5# by Eric S. Raymond <esr@thyrsus.com>, May 2003
6#
7# In Unixland, the magic is in knowing what to string together...
8#
9# Take grap description on stdin, emit cropped bitmap on stdout.
10# The pic markup should *not* be wrapped in .G1/.G2, this script will do that.
11# A -U option on the command line enables gpic/groff "unsafe" mode.
12# A -format FOO option changes the image output format to any format
13# supported by convert(1).  All other options are passed to convert(1).
14# The default format is PNG.
15#
16
17# Requires the groff suite and the ImageMagick tools.  Both are open source.
18# This code is released to the public domain.
19#
20# Here are the assumptions behind the option processing:
21#
22# 1. None of the options of grap(1) are relevant.
23#
24# 2. Only the -U option of groff(1) is relevant.
25#
26# 3. Many options of convert(1) are potentially relevant, (especially 
27# -density, -interlace, -transparency, -border, and -comment).
28#
29# Thus, we pass -U to groff(1), and everything else to convert(1).
30#
31# $Id: grap2graph.sh,v 1.4 2005/05/18 07:03:06 wl Exp $
32#
33groff_opts=""
34convert_opts=""
35format="png"
36
37while [ "$1" ]
38do
39    case $1 in
40    -unsafe)
41	groff_opts="-U";;
42    -format)
43	format=$2
44	shift;;
45    -v | --version)
46	echo "GNU grap2graph (groff) version @VERSION@"
47	exit 0;;
48    --help)
49	echo "usage: grap2graph [ option ...] < in > out"
50	exit 0;;
51    *)
52	convert_opts="$convert_opts $1";;
53    esac
54    shift
55done
56
57# create temporary directory
58tmp=
59for d in "$GROFF_TMPDIR" "$TMPDIR" "$TMP" "$TEMP" /tmp; do
60    test -z "$d" && continue
61
62    tmp=`(umask 077 && mktemp -d -q "$d/grap2graph-XXXXXX") 2> /dev/null` \
63    && test -n "$tmp" && test -d "$tmp" \
64    && break
65
66    tmp=$d/grap2graph$$-$RANDOM
67    (umask 077 && mkdir $tmp) 2> /dev/null && break
68done;
69if test -z "$tmp"; then
70    echo "$0: cannot create temporary directory" >&2
71    { (exit 1); exit 1; }
72fi
73
74trap 'exit_status=$?; rm -rf $tmp && exit $exit_status' 0 2 15 
75
76# Here goes:
77# 1. Add .G1/.G2.
78# 2. Process through grap(1) to emit pic markup.
79# 3. Process through groff(1) with pic preprocessing to emit Postscript.
80# 4. Use convert(1) to crop the Postscript and turn it into a bitmap.
81(echo ".G1"; cat; echo ".G2") | grap | groff -p $groff_opts -Tps -P-pletter | \
82    convert -trim -crop 0x0 $convert_opts - $tmp/grap2graph.$format \
83    && cat $tmp/grap2graph.$format
84
85# End
86