if [ "$1" == "zoom_in" ]; then
nvidia-settings --assign CurrentMetaMode="HDMI-0: 1360x768_60 +0+0 { ViewPortIn=800x600 }"
fi 
if [ "$1" == "zoom_out" ]; then
nvidia-settings --assign CurrentMetaMode="HDMI-0: 1360x768_60 +0+0 { ViewPortIn=1360x768 }"
fi