Merge (montage) multiple DOT files in a single PNG. #bash #graphviz #montage #dot

montage-dot.sh

#!/bin/bash

#
# Create a single PNG image from a sequence of DOT files (describing a graph)
#

# Parse command line

outfile="graph.png"

while getopts ":ho:" opt; do
    case $opt in
        o)
            outfile="${OPTARG}"
            ;;
        h)
            echo "Usage: ${0} -o <outfile> <input1.dot> <input2.dot> ..."
            ;;
        ?)
            echo "Invalid option: ${OPTARG}"
            ;;
    esac
done
shift $((OPTIND-1))

# Create temporary images for each DOT

n=${#}
images=( )
let i=0
for dotfile in ${@}; do
    name=$(basename "$dotfile")
    f=$(tempfile --prefix "${name%%.dot}")
    dot -Tpng ${dotfile} > ${f}
    images[$i]=${f}
    let i=i+1
done

# Montage

echo "${outfile}" 
montage ${images[*]} -tile "${n}x1" -geometry +5+0 ${outfile}

# Cleanup temporary files

for f in ${images[@]}; do rm ${f}; done