If you want to make a 3rd person camera, just follow these 3 easy steps
1. Get the position of your character
2. Use a addCameraSceneNode and point it to look at your character
3. Program the inputs(usually mouse) to move the camera around the character in a circling pattern using trigonometry we learned way back in calculus class...
You dont need to change the direction of the camera because your camera is always "behind" the character. Since your looking towards your character, the camera will always look forward.