I think the most effective and general purpose solution would be to use a Bezier Curve / 'Spline' interpolation technique -

Anything that interacts with the player would have something along the lines of:

var x : float;
var y : float;
private var spline : SplinePath;

function CalculatePosition() : Vector3 {
  return spline.WorldPosition( x ) + Vector3(0,y,0);
}

A SplinePath would consist of a series of points, and when you ask it for a position it will choose a point along a smooth path based on those points.

The idea is that .WorldPosition(x) will calculate the ground level at a certain "X" position in the level, then you'll add on any vertical changes your character has (jumping, etc).

Obviously the tough part of this is the SplinePath.WorldPosition function, but there are quite a few examples of this on the web. If I remember correctly there's a very nice Spline script available on the unity3d forums in the scripting section. If it's not exactly what you need, it'll be pretty close. Try searching for Spline or Bezier curve paths.

Just put an example together on the support site for iTween that I hope helps out with this. If you parent the camera to the character in this example and offset it from its right shoulder you will be able to have a camera that follows around curves. Hope it helps: http://itween.pixelplacement.com/examples.php

You should also take a look at iTween it has a few path interpolation options that migth help you out.

You might have a trigger that tells your camera and player that they are on a corner. Then maybe a distance check and/or dot product once they enter the trigger to determine the orientation of the camera and player...A trigger based system is probably the easiest to implement.

Hey there!

I'm the guy who created the spline system :)

I believe that it should do exactly what you're looking for. Oddly enough the code that I'm looking at doesn't have a flag that I remember adding for whether to affect the object's rotation. The default behavior should be to Lerp the object's rotation so that it's Z is looking down the spline in the direction that it's moving.

Lines 197-204 in SplineController should do that. If they aren't maybe your rotation damping value is at 0 for some reason? Let me know if you still can't get this to work!