FlyCam for Unity3D (Javascript)

#pragma strict

    /*Writen by Windexglow 11-13-10.  Use it, edit it, steal it I don't care.
    Simple flycam I made, since I couldn't find any others made public.
    Made simple to use (drag and drop, done) for regular keyboard layout
    wasd : basic movement
    shift : Makes camera accelerate
    left shift : Moves camera on X and Z axis only.  So camera doesn't gain any height
    space : Moves camera straight up
    X : Moves camera straight down*/

    var mainSpeed : float = 50.0; //regular speed
    var shiftAdd : float = 250.0; //multiplied by how long shift is held.  Basically running
    var maxShift : float = 1000.0; //Maximum speed when holdin gshift
    var camSens : float = 0.25; //How sensitive it with mouse
    private var lastMouse = Vector3(255, 255, 255); //kind of in the middle of the screen, rather than at the top (play)
    private var totalRun : float  = 1.0;

    function Update ()
    {
        lastMouse = Input.mousePosition - lastMouse;
        lastMouse = Vector3(-lastMouse.y * camSens, lastMouse.x * camSens, 0 );
        lastMouse = Vector3(transform.eulerAngles.x + lastMouse.x , transform.eulerAngles.y + lastMouse.y, 0);
        transform.eulerAngles = lastMouse;
        lastMouse =  Input.mousePosition;
        //Mouse & camera angle done.


        //Keyboard commands
        var f : float = 0.0;
        var p = GetBaseInput();
        if (Input.GetKey (KeyCode.LeftShift))
        {
            totalRun += Time.deltaTime;
            p  = p * totalRun * shiftAdd;
            p.x = Mathf.Clamp(p.x, -maxShift, maxShift);
            p.y = Mathf.Clamp(p.y, -maxShift, maxShift);
            p.z = Mathf.Clamp(p.z, -maxShift, maxShift);
        }
        else
        {
            totalRun = Mathf.Clamp(totalRun * 0.5, 1, 1000);
            p = p * mainSpeed;
        }

        p = p * Time.deltaTime;
        if (Input.GetKey(KeyCode.LeftShift))
        {
            //If player wants to move on X and Z axis only
            f = transform.position.y;
            transform.Translate(p);
            transform.position.y = f;
        }
        else
        {
            transform.Translate( p);
        }

    }



    private function GetBaseInput() : Vector3
    {
        //returns the basic values, if it's 0 than it's not active.
        var p_Velocity : Vector3;
        if (Input.GetKey (KeyCode.W))
        {
            p_Velocity += Vector3(0, 0 , 1);
        }
        if (Input.GetKey (KeyCode.S))
        {
            p_Velocity += Vector3(0, 0 , -1);
        }
        if (Input.GetKey (KeyCode.A))
        {
            p_Velocity += Vector3(-1, 0 , 0);
        }
        if (Input.GetKey (KeyCode.D))
        {
            p_Velocity += Vector3(1, 0 , 0);
        }
        if (Input.GetKey (KeyCode.Space))
        {
            p_Velocity += Vector3(0,1,0);
        }
        if (Input.GetKey (KeyCode.X))
        {
            p_Velocity += Vector3(0,-1,0);
        }
        return p_Velocity;
    }