#!/bin/sh function usage() { NAME=$(basename "$0") echo "Usage: ${NAME} " } IN_FILE="$1" OUT_DIR="$2" if [[ ! -r "$IN_FILE" ]]; then echo "Missing source icon, or file not found: $IN_FILE" usage exit 1 fi if [[ ! -d "$OUT_DIR" ]]; then echo "Missing output directory, or directory not found: $OUT_DIR" usage exit 2 fi for SIZE in 29 40 60 76; do echo "* Generating app icons at $SIZE points" retina-scale $SIZE "$IN_FILE" "$OUT_DIR" done