drm - Use x11-libs/libdrm for more verbose diagnostics.
introspection - Add support for GObject based introspection
usb-monitor - Adds support for monitors attached via USB.
user-permissions - Adds a udev rules to allow non-root users in the i2c group to access the /dev/i2c-* devices. If usb-monitor is selected, users will need to be added to the video group to access the USB monitor. Otherwise, only root will be able to use ddcutil.
video_cards_nvidia - VIDEO_CARDS setting to build driver for nvidia video cards
