Xcode Bash Script for On-Demand PVR Texture Encoding

Do you know those tiny little things that always annoy you – for a reeaaaallly long time – but you never get around to fix them? For me, one of those things was the custom build phase step to convert my texture to compressed PVR format. Streetsoccer uses some big textures for the ground as well as the skymap and for some reason, xcode seemed to often rebuild those PVRs. So I just sat down and finally modified my build script to check if the PVR version already exists.

To be honest, before rewriting the script, Xcode sometimes did rebuild the PVRs and sometimes it did not. So perhaps this is a moot point and texturetool does this internally, but I don’t thing so. Anyway, here goes:

function convert
{
    # Only convert if PVR does not exist or source texture has a more recent date
    if [ ! -f "$2" ] || [ "$1" -nt "$2" ]; then
    echo converting "$1" to "$2"
    xcrun -sdk iphoneos texturetool -m -e PVRTC --bits-per-pixel-4 -o "$2" -f PVR "$1"
    else
    echo skipping "$2", already up-to-date 
    fi
}

convert "$SRCROOT/Models/BallDiffuseMap.png" "$SRCROOT/Models/PVR/BallDiffuseMap.pvr"
convert "$SRCROOT/Models/Baselayer.png" "$SRCROOT/Models/PVR/Baselayer.pvr"
convert "$SRCROOT/Models/BlueGoalieDiffuseMap.png" "$SRCROOT/Models/PVR/BlueGoalieDiffuseMap.pvr"

# ... of course you got to modify this list to match your textures and folders ...