#!/bin/bash
#
# svg_convertPngToSyslinux.sh -- This function provides post-rendition
# action used to produce LSS16 images, the images used by isolinux.
#
# Initially, the color information is defined with GIMP (The GNU Image
# Manipulation Program) as a `.gpl' palette of color. This palette of
# colors contains 16 colors only and is saved in a file named
# `syslinux.gpl. The `syslinux.gpl' file is used to build two other
# files: the `syslinux.ppm' file and the `syslinux.hex' file. The
# `syslinux.ppm' provides the color information needed to reduce the
# full color PNG image, produced as result of SVG base-rendition, to
# the amount of colors specified (i.e., 16 colors). Later, with the 16
# color PNG image already created, the `syslinux.hex' file is used to
# build the LSS16 image.
#
# In order to produce images in LSS16 format correctly, it is required
# that both the `syslinux.ppm' and `syslinux.hex' files do contain the
# same color information. This is, both `syslinux.ppm' and
# `syslinux.hex' must represent the same color values and in the same
# color index.
#
# In order for this function to work, the `syslinux.gpl' file should
# have a format similar to the following:
#
# GIMP Palette
# Name: CentOS-TreeFlower-4-Syslinux
# Columns: 16
# #
# 32 76 141 204c8d
# 37 82 146 255292
# 52 94 153 345e99
# 73 110 162 496ea2
# 91 124 172 5b7cac
# 108 136 180 6c88b4
# 120 146 186 7892ba
# 131 158 193 839ec1
# 255 255 255 ffffff
# 146 170 200 92aac8
# 162 182 209 a2b6d1
# 183 199 219 b7c7db
# 204 216 230 ccd8e6
# 221 229 238 dde5ee
# 235 241 245 ebf1f5
# 246 251 254 f6fbfe
#
# Copyright (C) 2009-2013 The CentOS Project
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or (at
# your option) any later version.
#
# This program is distributed in the hope that it will be useful, but
# WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
# General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
#
# ----------------------------------------------------------------------
# $Id$
# ----------------------------------------------------------------------
function svg_convertPngToSyslinux {
# Define number of colors the images will be produced on.
local COLORS='16'
# Define options using those passed to actions from pre-rendition
# configuration script. These options are applied to pnmremap when
# doing color reduction, so any option available for pnmremap
# command can be passed to renderSyslinux functionality.
local OPTIONS=$(render_getConfigOption "$ACTION" '2-')
# Check options passed to action. This is required in order to
# aviod using options already used in this script. For example
# -verbose and -mapfile options.
for OPTION in $OPTIONS;do
# Remove anything after equal sign inside option.
OPTION=$(echo $OPTION | cut -d'=' -f1)
if [[ "$OPTION" =~ "-(mapfile|verbose)" ]];then
cli_printMessage "`eval_gettext "The \\\"\\\$OPTION\\\" option is already used."`" --as-error-line
fi
done
# Define default file name prefix for 16 colors images.
local PREFIX="-${COLORS}c"
# Re-define 16 colors images default file name prefix using
# options as reference. This is useful to differenciate final
# files produced using Floyd-Steinberg dithering and final files
# which are not.
if [[ "$OPTIONS" =~ '-floyd' ]];then
PREFIX="${PREFIX}-floyd"
fi
# Define logs' file. Log files are stored in the same place of
# images and are used to store output information produced by
# programs when the image files are built up.
local LOGS=${FILE}${PREFIX}.log
# Define absolute path to GPL palette. The GPL palette defines the
# color information used to build syslinux images. This palette
# should be set to 16 colors and, as specified in isolinux
# documentation, the background color should be indexed on
# position 0 and the forground in position 7 (see
# /usr/share/doc/syslinux-X.XX/isolinux.doc, for more
# information.)
local PALETTE_GPL=${MOTIF_DIR}/Palettes/syslinux.gpl
# Verify GPL palette existence. If it doesn't exist copy the one
# provided by the design model through subversion (to keep track
# of the change) and expand translation markers in the copied
# instance.
if [[ ! -f $PALETTE_GPL ]];then
cli_runFnEnvironment vcs --copy ${MODEL_BASEDIR}/${FLAG_THEME_MODEL}/Palettes/syslinux.gpl ${PALETTE_GPL}
cli_expandTMarkers ${PALETTE_GPL}
fi
# Define absolute path to PPM palette. The PPM palette is built
# from source palette (PALETTE_GPL) and provides the color
# information understood by `ppmremap', the program used to
# produce images in a specific amount of colors.
local PALETTE_PPM=$(cli_getTemporalFile "syslinux.ppm")
# Define the HEX palette. The HEX palette is built from source
# palette (PALETTE_GPL) and provides the color information in the
# format understood by `ppmtolss16', the program used to produce
# images in LSS16 format. The HEX palette stores just one line
# with the color information as described in isolinux
# documentation (i.e #RRGGBB=0 #RRGGBB=1 ... [all values in the
# same line])
local PALETTE_HEX=$(cli_getTemporalFile "syslinux.hex")
# Create image in Netpbm superformat (PNM). The PNM image file is
# created from the PNG image rendered previously as centos-art
# base-rendition output. The PNM image is an intermediate format
# used to manipulate images through Netpbm tools.
cli_printMessage "${FILE}.pnm" --as-savedas-line
pngtopnm -verbose \
< ${FILE}.png 2>${LOGS} > ${FILE}.pnm
# Print the path to GPL palette.
cli_printMessage "$PALETTE_GPL" --as-palette-line
# Create PPM palette using GPL palette.
svg_convertGplToPpm "$PALETTE_GPL" "$PALETTE_PPM" "$COLORS"
# Create HEX palette using GPL palette.
svg_convertGplToHex "$PALETTE_GPL" "$PALETTE_HEX" "$COLORS"
# Reduce colors as specified in PPM palette. Here we use the PPM
# palette to enforce the color position in the image index and the
# Floyd-Steinberg dithering in order to improve color reduction.
cli_printMessage "${FILE}${PREFIX}.pnm" --as-savedas-line
pnmremap -verbose -mapfile=$PALETTE_PPM $OPTIONS \
< ${FILE}.pnm 2>> ${LOGS} > ${FILE}${PREFIX}.pnm
# Create LSS16 image.
cli_printMessage "${FILE}${PREFIX}.lss" --as-savedas-line
ppmtolss16 $(cat $PALETTE_HEX) \
< ${FILE}${PREFIX}.pnm 2>>${LOGS} > ${FILE}${PREFIX}.lss
# Remove HEX palette. It is no longer needed.
if [[ -f ${PALETTE_HEX} ]];then
rm $PALETTE_HEX
fi
# Create PPM image indexed to 16 colors. Also the colormap used in
# the LSS16 image is saved on ${FILE}.log; this is useful to
# verify the correct order of colors in the image index.
cli_printMessage "${FILE}${PREFIX}.ppm" --as-savedas-line
lss16toppm -map \
< ${FILE}${PREFIX}.lss 2>>${LOGS} > ${FILE}${PREFIX}.ppm
# Create PNG image indexed to 16 colors.
cli_printMessage "${FILE}${PREFIX}.png" --as-savedas-line
pnmtopng -verbose \
< ${FILE}${PREFIX}.pnm 2>>${LOGS} > ${FILE}${PREFIX}.png
# Remove PPM palette. It is no longer needed.
if [[ -f ${PALETTE_PPM} ]];then
rm $PALETTE_PPM
fi
}