#!/bin/sh

HALF_RES_RESOLUTIONS="240 320 360 480 540 600 720 768 800 1080 1200 1440 1536 1600"

for i in $HALF_RES_RESOLUTIONS; do
	rm -f $i.zip
	mkdir $i
	cd $i
	if [ -f ../../$(($i/2)).zip ]; then
		# use the existing scaled images
		echo "Using existing half-scale images instead of scaling from $i px"
		unzip ../../$(($i/2)).zip
		rm -f desc.txt
		unzip ../../$i.zip desc.txt
	else
		unzip ../../$i.zip
		for j in */*.[pP][nN][gG]; do
			convert $j -resize 50% tmp.png
			mv tmp.png $j
		done
	fi
	zip -r0 ../$i.zip .
	cd ..
	rm -rf $i
done