#! /bin/sh
-# \file tex2preview.sh
-# Copyright 2002 the LyX Team
-# Read the file COPYING
-# \author Angus Leeming, leeming@lyx.org
+# file lyxpreview2bitmap.sh
+# This file is part of LyX, the document processor.
+# Licence details can be found in the file COPYING.
+#
+# author Angus Leeming
# with much advice from David Kastrup, david.kastrup@t-online.de.
+#
+# Full author contact details are available in file CREDITS
# This script takes a LaTeX file and generates bitmap image files,
# one per page.
# The idea is to use it with preview.sty from the preview-latex project
-# (http://preview-latex.sourceforge.net/) to create small bitmap previews of
-# things like math equations.
+# (http://preview-latex.sourceforge.net/) to create small bitmap
+# previews of things like math equations.
-# preview.sty can be obtained from CTAN/macros/latex/contrib/supported/preview.
+# preview.sty can be obtained from
+# CTAN/macros/latex/contrib/supported/preview.
# This script takes three arguments:
# TEXFILE: the name of the .tex file to be converted.
# SCALEFACTOR: a scale factor, used to ascertain the resolution of the
# generated image which is then passed to gs.
-# OUTPUTFORMAT: the format of the output bitmap image files. Two formats
-# are recognised: PPM and PNG
+# OUTPUTFORMAT: the format of the output bitmap image files.
+# Two formats are recognised: "ppm" and "png".
# If successful, this script will leave in dir ${DIR}:
-# ${BASE}\([0-9]*\).ppm/png: a (possibly large) number of image files.
-# ${BASE}.metrics: a file containing info needed by LyX to
-# position the images correctly on the screen.
+# a (possibly large) number of image files with names like
+# ${BASE}\([0-9]*\).${SUFFIX} where SUFFIX is ppm or png.
+# a file containing info needed by LyX to position the images correctly
+# on the screen.
+# ${BASE}.metrics
# All other files ${BASE}* will be deleted.
+# A quick note on the choice of OUTPUTFORMAT:
+
+# In general files in PPM format are 10-100 times larger than the
+# equivalent files in PNG format. Larger files results in longer
+# reading and writing times as well as greater disk usage.
+
+# However, whilst the Qt image loader can load files in PNG format
+# without difficulty, the xforms image loader cannot. They must first
+# be converted to a loadable format (eg PPM!). Thus, previews will take
+# longer to appear if the xforms loader is used to load snippets in
+# PNG format.
+
+# You can always experiment by adding a line to your
+# ${LYXUSERDIR}/preferences file
+# \converter lyxpreview ${FORMAT} "lyxpreview2bitmap.sh" ""
+# where ${FORMAT} is either ppm or png.
+
# Three helper functions.
-FIND_IT () {
- which ${EXECUTABLE} > /dev/null
- if [ $? -ne 0 ]; then
- echo "Unable to find \"${EXECUTABLE}\". Please install."
+FIND_IT ()
+{
+ test $# -eq 1 || exit 1
+
+ type $1 > /dev/null || {
+ echo "Unable to find \"$1\". Please install."
exit 1
- fi
+ }
}
-BAIL_OUT () {
+BAIL_OUT ()
+{
# Remove everything except the original .tex file.
FILES=`ls ${BASE}* | sed -e "/${BASE}.tex/d"`
rm -f ${FILES} texput.log
+ echo "Leaving ${BASE}.tex in ${DIR}"
exit 1
}
-REQUIRED_VERSION () {
+REQUIRED_VERSION ()
+{
echo "We require preview.sty version 0.73 or newer. You're using"
grep 'Package: preview' ${LOGFILE}
}
fi
# We use latex, dvips and gs, so check that they're all there.
-EXECUTABLE=latex; FIND_IT
-EXECUTABLE=dvips; FIND_IT
-EXECUTABLE=gs; FIND_IT
+FIND_IT latex
+FIND_IT dvips
+FIND_IT gs
# Initialise some variables.
TEXFILE=${BASE}.tex
# LaTeX -> DVI.
cd ${DIR}
-latex ${TEXFILE}
-if [ $? -ne 0 ]; then
+latex ${TEXFILE} ||
+{
echo "Failed: latex ${TEXFILE}"
BAIL_OUT
-fi
+}
-# Parse ${LOGFILE} to obtain bounding box info to output to ${METRICSFILE}.
-# This extracts lines starting "Preview: Tightpage" and "Preview: Snippet".
-grep -E 'Preview: [ST]' ${LOGFILE} > ${METRICSFILE}
-if [ $? -ne 0 ]; then
+# Parse ${LOGFILE} to obtain bounding box info to output to
+# ${METRICSFILE}.
+# This extracts lines starting "Preview: Tightpage" and
+# "Preview: Snippet".
+grep -E 'Preview: [ST]' ${LOGFILE} > ${METRICSFILE} ||
+{
echo "Failed: grep -E 'Preview: [ST]' ${LOGFILE}"
REQUIRED_VERSION
BAIL_OUT
-fi
+}
# Parse ${LOGFILE} to obtain ${RESOLUTION} for the gs process to follow.
# 1. Extract font size from a line like "Preview: Fontsize 20.74pt"
-# Use grep for speed and because it gives an error if the line is not found.
-LINE=`grep 'Preview: Fontsize' ${LOGFILE}`
-if [ $? -ne 0 ]; then
+# Use grep for speed and because it gives an error if the line is
+# not found.
+LINE=`grep 'Preview: Fontsize' ${LOGFILE}` ||
+{
echo "Failed: grep 'Preview: Fontsize' ${LOGFILE}"
REQUIRED_VERSION
BAIL_OUT
-fi
-# Use "" quotes in the echo to preserve newlines (technically IFS separators).
-# The sed script strips out everything that won't form a decimal number from the
-# line. It bails out after the first match has been made in case there are
-# multiple lines "Preview: Fontsize". (There shouldn't be.)
+}
+# The sed script strips out everything that won't form a decimal number
+# from the line. It bails out after the first match has been made in
+# case there are multiple lines "Preview: Fontsize". (There shouldn't
+# be.)
+# Note: use "" quotes in the echo to preserve newlines.
LATEXFONT=`echo "${LINE}" | sed 's/[^0-9\.]//g; 1q'`
-# 2. Extract magnification from a line like "Preview: Magnification 2074"
+# 2. Extract magnification from a line like
+# "Preview: Magnification 2074"
# If no such line found, default to MAGNIFICATION=1000.
LINE=`grep 'Preview: Magnification' ${LOGFILE}`
-if [ $? -ne 0 ]; then
- MAGNIFICATION=1000
-else
- # The sed script strips out everything that won't form an /integer/.
+if LINE=`grep 'Preview: Magnification' ${LOGFILE}`; then
+ # Strip out everything that won't form an /integer/.
MAGNIFICATION=`echo "${LINE}" | sed 's/[^0-9]//g; 1q'`
+else
+ MAGNIFICATION=1000
fi
# 3. Compute resolution.
# "bc" allows floating-point arithmetic, unlike "expr" or "dc".
RESOLUTION=`echo "scale=2; \
- ${SCALEFACTOR} * (10/${LATEXFONT}) * (1000/${MAGNIFICATION})" \
- | bc`
+ ${SCALEFACTOR} * (10/${LATEXFONT}) * (1000/${MAGNIFICATION})" \
+ | bc`
# DVI -> PostScript
-dvips -o ${PSFILE} ${DVIFILE}
-if [ $? -ne 0 ]; then
+dvips -o ${PSFILE} ${DVIFILE} ||
+{
echo "Failed: dvips -o ${PSFILE} ${DVIFILE}"
BAIL_OUT
-fi
+}
# PostScript -> Bitmap files
-# Older versions of gs have problems with a large degree of anti-aliasing
-# at high resolutions
+# Older versions of gs have problems with a large degree of
+# anti-aliasing at high resolutions
-# test expects integer arguments. ${RESOLUTION} may be a float. Truncate it.
+# test expects integer arguments.
+# ${RESOLUTION} may be a float. Truncate it.
INT_RESOLUTION=`echo "${RESOLUTION} / 1" | bc`
ALPHA=4
fi
gs -q -dNOPAUSE -dBATCH -dSAFER \
- -sDEVICE=${GSDEVICE} -sOutputFile=${BASE}%d.${GSSUFFIX} \
- -dGraphicsAlphaBit=${ALPHA} -dTextAlphaBits=${ALPHA} -r${RESOLUTION} \
- ${PSFILE}
-
-if [ $? -ne 0 ]; then
+ -sDEVICE=${GSDEVICE} -sOutputFile=${BASE}%d.${GSSUFFIX} \
+ -dGraphicsAlphaBit=${ALPHA} -dTextAlphaBits=${ALPHA} \
+ -r${RESOLUTION} ${PSFILE} ||
+{
echo "Failed: gs ${PSFILE}"
BAIL_OUT
-fi
+}
# All has been successful, so remove everything except the bitmap files
# and the metrics file.
-FILES=`ls ${BASE}* | \
- sed -e "/${BASE}.metrics/d" -e "/${BASE}\([0-9]*\).${GSSUFFIX}/d"`
+FILES=`ls ${BASE}* | sed -e "/${BASE}.metrics/d" \
+ -e "/${BASE}\([0-9]*\).${GSSUFFIX}/d"`
rm -f ${FILES} texput.log
+
+# The bitmap files can have large amounts of whitespace to the left and
+# right. This can be cropped if so desired.
+CROP=1
+type pnmcrop > /dev/null || CROP=0
+
+# There's no point cropping the image if using PNG images. If you want to
+# crop, use PPM.
+# Apparently dvipng will support cropping at some stage in the future...
+if [ ${CROP} -eq 1 -a "${GSDEVICE}" = "pnmraw" ]; then
+ for FILE in ${BASE}*.${GSSUFFIX}
+ do
+ if pnmcrop -left ${FILE} 2> /dev/null |\
+ pnmcrop -right 2> /dev/null > ${BASE}.tmp; then
+ mv ${BASE}.tmp ${FILE}
+ else
+ rm -f ${BASE}.tmp
+ fi
+ done
+ rm -f ${BASE}.tmp
+fi
+
+echo "Previews generated!"
projects / lyx.git / blobdiff