make_tiles.sh

#!/bin/bash

# make_tiles.sh
# Copyright 2010 Aleksandr Pasechnik
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# 	http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

usage() {
	cat << EOF
usage $0 options

This script will convert the submitted file into a collection of tiles for use with the TileViewer jquery plugin.

Options:
	-h	Shows this message
	-i	Source file name (required)
	-o	Output directory (required).  This directory will be irrevocably removed if it already exists!
	-t	Output file type, "jpg" by defult.  May be anything ImageMagic supports as an image output file (jpg, png, gif)
	-b	Background color, "#444" by default.
	-s	Tile size in pixels, 256 by default

EOF
}

source="none"
outputdir="none"
type="jpg"
background="#444"
tile_size=256
while getopts ":hi:o:t:b:s:" OPTION; do
	case $OPTION in
		h)
			usage
			exit 1
			;;
		i)
			source=$OPTARG
			;;
		o)
			outputdir=`echo $OPTARG | sed 's_/$__'`
			;;
		t)
			type=$OPTARG
			;;
		b)
			background=$OPTARG
			;;
		s)
			tile_size=$OPTARG
			;;
		?)
			usage
			exit 1
			;;
	esac
done
if [[ "$source" == "none" ]] || [[ "$outputdir" == "none" ]]; then
	usage
	exit 1
fi

rm -r "$outputdir"
mkdir "$outputdir"

args="-monitor "
args=$args"-background "$background" -gravity center "

source_width=`identify -format "%w" $source`
source_height=`identify -format "%h" $source`
levels=`python -c "from math import *; print int(ceil(log(ceil(min($source_width,$source_height)/$tile_size),2))+1)"`
echo "Will make "$levels" levels"
echo

level=0
while [[ $level < $levels ]]; do
	leveldir="$outputdir/level$level"
	mkdir $leveldir
	if [[ $level == 0 ]]; then
		full_width=`python -c "import math; print int(math.ceil(1.0 * $source_width / (2 ** $levels)) * 2 ** $levels)"`
		full_height=`python -c "import math; print int(math.ceil(1.0 * $source_height / (2 ** $levels)) * 2 ** $levels)"`
		args=$args"( "$source" -strip -extent "$full_width"x"$full_height" ) "
	fi
	current_width=`python -c "print int($full_width / (2 ** $level))"`
	current_height=`python -c "print int($full_height / (2 ** $level))"`
	padded_width=`python -c "import math; print int((math.ceil($current_width/$tile_size)+1)*$tile_size)"`
	padded_height=`python -c "import math; print int((math.ceil($current_height/$tile_size)+1)*$tile_size)"`
	args=$args"( -clone 0 -scale "$current_width"x"$current_height" -extent "$padded_width"x"$padded_height" \
	-crop "$tile_size"x"$tile_size" +repage -write "$leveldir"/tile-%d."$type" ) "

	cols_in_level[$level]=`echo "$padded_width / $tile_size" | bc`
	rows_in_level[$level]=`echo "$padded_height / $tile_size" | bc`
	tiles_in_level[$level]=$(( ${cols_in_level[$level]} * ${rows_in_level[$level]} ))

	level=$(( $level + 1 ))
done

args=$args" -delete 0 null:"

echo "about to run"
echo "convert "$args
echo

echo $args | xargs convert

echo
echo "Writing json file"
cat > "$outputdir/settings.json" << ENDJS
{
	"tile_size" : $tile_size,
	"levels" : $level,
	"tiles_in_level" : [`echo ${tiles_in_level[@]} | sed "s/ /, /g"`],
	"cols_in_level" : [`echo ${cols_in_level[@]} | sed "s/ /, /g"`],
	"rows_in_level" : [`echo ${rows_in_level[@]} | sed "s/ /, /g"`],
	"filetype" : "$type",
	"background_color" : "$background"
}
ENDJS
echo