How to create the "drunk camera" effect in GTA 4?

Question

If you have played GTA 4, then you have probably been drunk at some stage. This is one of the best intoxicated simulators I have ever seen. It is actually hard or sometimes almost impossible to drive a vehicle while drunk in this game.

I know that a lot of the things that make up this drunk experience are changes to the controls or having random changes in direction, but how would the camera be done?

The camera seems to wave in and out and side to side. It also has changing blur, and other effects going on. Would this be some kind of shader? What are the effects that are used on top of each other to create the experience?

Answer 1

Some things you could do are sway the camera, delay the controls, make the controls unresponsive or unpredictable, as well as blend in previous frames.

Answer 2

Oh man this game should be used for drunk driving reeducation, because the one thing that I learned about drinking from this game is that the results suck.

I think they were doing a couple of things, although I haven't played it since it was new so my memory may be fuzzy. One big thing you can do is change the FOV. Then you can swirl the camera location around and maybe even the look-at position. Finally, to get truly vertigo inducing, you could skew the frustum.

Answer 3

Also, a general tip for making a distortion effect is that you can render the scene onto another plane overlaid on the scene, and then warp that plane. This is useful for other things too, because you can have the overlay partially transparent (flash bang effect maybe?).