Making non-Retina graphics

make_non_retina_graphics.sh

#!/bin/bash

# Your designer should be making you assets in both resolutions.
# By that, I mean they don’t just resize in Photoshop and export,
# but they actually *design* for both resolutions. Failing that,
# run this. You’ll need ImageMagick installed and in your PATH.

# The script will operate on *all* images in the current directory
# with the suffix @2*.png. Why @2* instead of @2x? In case you do
# this for iPhone 5:
#
# [email protected]
#
# Why would you want non-retina iPhone 5 graphics? Easy: Interface
# Builder.

for x in *@2*.png; do
    newfilename="$(echo $x | sed -e 's/@2x//g')"

    if [ ! -f "$newfilename" ]; then
        echo $newfilename
        convert $x -resize 50% $newfilename
    fi
done