Spirit of Half-Life (SoHL) is a modified game engine for Half-Life 1 modders that includes many new things not seen in the original Half-Life engine by Valve. This includes reflections, mirrors better lighting, weather like moving clouds, rain, snow, and fog. Physics capabilities like picking up objects and dropping them, or when some thing explodes objects go flying off in the direction.
what is this?
pretty sure its supposed to show transparent vent cover, but the darkness makes it hard to see..