visual_compare.sh

#!/bin/bash

ask() {
    # https://djm.me/ask
    local prompt default reply

    while true; do

        if [ "${2:-}" = "Y" ]; then
            prompt="Y/n"
            default=Y
        elif [ "${2:-}" = "N" ]; then
            prompt="y/N"
            default=N
        else
            prompt="y/n"
            default=
        fi

        # Ask the question (not using "read -p" as it uses stderr not stdout)
        echo -n "$1 [$prompt] "

        # Read the answer (use /dev/tty in case stdin is redirected from somewhere else)
        read reply </dev/tty

        # Default?
        if [ -z "$reply" ]; then
            reply=$default
        fi

        # Check if the reply is valid
        case "$reply" in
            Y*|y*) return 0 ;;
            N*|n*) return 1 ;;
        esac

    done
}

if ! [ -e './replace_baseplate.sh' ]; then
    echo 'You need replace_baseplate.sh present.'
    exit 1
fi

while read -r __name; do
    if ! which "${__name}" &> /dev/null; then
        echo "You need ${__name} installed"
        exit 1
    fi
done <<< 'parallel
rsvg-convert
composite'

if ! ask "This will discard any changes to icon and create some file, continue?"; then
    echo 'Okay.'
    exit 1
fi

git discard icons

mkdir -p ignore/visualdiff/original/circle
mkdir -p ignore/visualdiff/original/square

process_image () {
    __file="${!#}"
    __name="$(sed -e 's/^.*\/\(.*\).svg$/\1/' <<< "${__file}")"
    __output="ignore/visualdiff/${1}/${2}/${__name}.png"
    if ! [ -e "${__output}" ]; then
        echo "${__name}"
        rsvg-convert "${__file}" --zoom=2 -o "${__output}"
    fi
}

process_new () {
    process_image new "${@}"
}

process_original () {
    process_image original "${@}"
}

compare_image () {
    __file="${!#}"
    __name="$(sed -e 's/^.*\///' <<< "${__file}")"
    composite "ignore/visualdiff/new/${1}/${__name}" "ignore/visualdiff/original/${1}/${__name}" -compose difference "ignore/visualdiff/compare/${1}/${__name}"
}

export -f process_image process_new process_original compare_image

while read -r __theme; do

    find "icons/${__theme}/48/" -type f | sort | parallel -j10 process_original "${__theme}"

done <<< 'circle
square'

./replace_baseplate.sh

mkdir -p ignore/visualdiff/new/circle
mkdir -p ignore/visualdiff/new/square

while read -r __theme; do

    git diff --name-only "icons/${__theme}/48/" | sort | parallel -j10 process_new "${__theme}"

done <<< 'circle
square'

mkdir -p ignore/visualdiff/compare/circle
mkdir -p ignore/visualdiff/compare/square

while read -r __theme; do

    find "ignore/visualdiff/new/${__theme}/" -type f | sort | parallel -j10 compare_image "${__theme}"

done <<< 'circle
square'

exit