Generate an iOS app icon with a gradient background using an input image

icon_create.sh

#!/bin/sh

DIR="$( cd "$( dirname "${BASH_SOURCE[0]}" )" && pwd )"

FILE="$DIR/../Design/appicon-foreground.svg"
OUTPUT_LOCATION="$DIR/../iTunes"

# convert svg asset to png
convert -density 2000 -resize 1024x1024 -background none $FILE appicon-foreground.png

# create a linear gradient background
convert -size 1024x1024 -define gradient:direction=southwest gradient:yellow-green linear_gradient.png

# overlay monkey on background
composite -gravity center appicon-foreground.png linear_gradient.png $OUTPUT_LOCATION/iTunesArtwork@2x.png

# delete intermediary assets
rm linear_gradient.png
rm appicon-foreground.png