In the French film "Grand Bleu" there is a scene where the hero touches water on the ceiling, how was it done

Question

I'm interested in the special effects aspect of this scene since I don't believe it was done using a computer. The main actor is lying in bed when he looks up at the ceiling and it turns into the ocean, he then touches it. Anyone know how this was created?

Answer 1

Huh, I would say a blue screen, unless it was actually filmed at a location where the mirror, if properly placed, picked up the image of the ocean outside? or have him looking through a hole in the floor where the ocean was underneath, with the bed "on the ceiling and the actor secured; then just reverse it in editing (but that would be a pain in the butt when we have special effects-plus a huge waste of time and money) they do have homes built over the water with glass panels looking to the waters below...

Answer 2

Maybe it was a split screen.