#!/bin/sh

if [ -z "${VGL_DISPLAY-}" ]; then
	# Use the dummy X server if it is enabled
	if [ "${SERVICE_XORG_HEADLESS_ENABLED:?}" = 'true' ]; then
		export VGL_DISPLAY=:0.0
	else
		# Otherwise try to use the EGL backend
		for card in /dev/dri/card*; do
			if /opt/VirtualGL/bin/eglinfo -B "${card:?}" 2>/dev/null; then
				export VGL_DISPLAY="${card:?}"
				break
			fi
		done
		# And fallback to DISPLAY if the EGL backend is not available
		if [ -z "${VGL_DISPLAY-}" ] && [ -n "${DISPLAY-}" ]; then
			export VGL_DISPLAY="${DISPLAY:?}"
		fi
	fi
fi
