zshrc: Add command to switch NVIDIA GPU in Mutter

zshrc

@@ -640,5 +640,32 @@ cross() {
 	)
 }
 
+if [ -e /dev/nvidia0 ]; then
+	nvidia() {
+		case "$1" in
+		1|on)
+			primary="/dev/dri/card0"
+			secondary="/dev/dri/card1"
+			;;
+		0|off)
+			primary="/dev/dri/card1"
+			secondary="/dev/dri/card0"
+			;;
+		*)
+			return 1
+			;;
+		esac
+
+		sudo tee /etc/udev/rules.d/61-mutter-primary-gpu.rules \
+			>/dev/null <<__EOF__
+ENV{DEVNAME}=="${primary}", TAG+="mutter-device-preferred-primary"
+ENV{DEVNAME}=="${secondary}", TAG=""
+__EOF__
+		sudo udevadm control --reload
+		sudo udevadm trigger
+		sudo systemctl restart gdm
+	}
+fi
+
 unset fgrep grep grep_color ls ls_color ls_on_cd ls_on_init
 unset HISTFILE