I'm making a map with a section in which gravity is reversed, and the player is attracted to the ceiling. The puzzle will pretty much be impossible to solve without being able to flip over and "crawl" on the ceiling. I've been messing around for a while with point_viewcontrol trying to make it flip the perspective but to no avail. Is scripting required for this? Or can I do it with map entities?

My solution to this would be, in memory of Einstein, to teleport the player to a different room, which looks exactly the same, but is flipped. A trigger_vphysics_motion would set a negative gravity for all physics objects.

agree entirely with brainstonex. Use a room with everything upsde down.

Create your room, cut it half so you have a top portion and a bottom portion, take the top half and turn it upside down so the "ceiling" is actually the floor, and then link the two halves of the room together with a linked_portal_door.

Here's a video that demonstrates different things you can do with linked_portal_doors, including changing gravity. http://www.youtube.com/watch?v=_xFbRecjKQA

Hope this helps!

These ideas all sound good and I'll try them, but I'm worrying about complexity of the level because I am planning to include it in a boss battle in the climax of my mod. I guess I shouldn't make it too complex then.

Hey wrathofmobius,

Did you ever play Nyskrte's "NYS-5" mappack for single player? well, in the beginning of map 5 he uses a room with different gravity values (inverted) up and down, as Blackrat suggests you to do: a room splitted in two by a midddle horizontal line...

The result is awesome, and that room is so funny and challenging as well