Biosys is a PC game released in 1999, where navigation through its environments is done by clicking an "exit" on a scene, taking the player to a new scene. The player can't move in a scene, and interaction is done by clicking a location in it. In some scenes the player can freely look around in 360 degrees by moving the mouse.
My question is, what technique could be used to render such a scene? I'm asking because that doesn't look like it's true 3D; it looks drawn as if a picture is wrapped around the player, but how would you produce and render a picture in such a way?
Here is a rare YouTube video of that game, beginning at 3:40 where the technique I'm curious about is shown.
And here's a picture of one of those environments: