CameraController (Smooth, X direction)

using UnityEngine;
using System.Collections;
using System;

// Add this script to the camera you want to follow the player
public class CameraController : MonoBehaviour
{
    // Player (the Transform of whatever you want the camera to follow)
    public Transform player;

    // Change this to match your game. This is the Y coordinate of where your camera will look.
    // It will only follow the player left and right, so make sure you position this correctly! :)
    public float constantYposition;

    // Increase to make the camera follow the player slower - or decrease for more instant gratification
    public float damping = 0.5f;

    // Used to keep track of the players previous position
    private Vector3 lastTargetPosition;

    // Sorry - I can't figure out what this is used for, as it apparently is never initialized.
    // However, this needs to be here so we can ref it in the SmoothDamp thing. :S
    private Vector3 currentVelocity;


    // Use this for initialization
    void Start()
    {
        // Save player position as last player position
        lastTargetPosition = player.position;

        // This will prevent the camera from following a parent - in case you added the camera as somethings child.
        // (which makes the camera follow whatever parent)
        transform.parent = null;
    }


    // Update is called once per frame
    void Update()
    {
        // Camera follows the player smoothly with this
        Vector3 newPos = Vector3.SmoothDamp(new Vector3(transform.position.x, constantYposition, transform.position.z), player.position, ref currentVelocity, damping);

        // Change the position to the camera
        transform.position = newPos;

        // Set player position as last camera position (helps us to give the effect of smoothly following the player)
        lastTargetPosition = player.position;
    }
}