# check if DRI is available, show an error and exit if it isn't
function checkDriOK ()
{
if [ `glxinfo | grep "direct rendering: " | cut -d " " -f 3` != Yes ]; then
zenity --error --text="Your system currently is not capable of hardware \
accelerated 3D. Therefor $1 cannot run.
Usually the cause of this error is that there are no Free Software drivers \
for your graphics card, please contact your graphics card manufacturer and \
kindly ask them to provide Free Software support for your card."
exit 1;
fi
}