Marwell Wildlife has at least two Ocelot and a viewing panel set into the indoor section of their enclosure. This has everything a cat needs for sleeping...shelves to sleep on and heat lamps to sleep under. At least the indoor part has a viewing window, so people can see the cats, even if they're hiding where the camera can't see.

At least on my March visit one of the Ocelot was moving around! Here it's seen crouched on the floor of the indoor area. Photo taken through the viewing window.