I would say your problem is your direction. If you use Raycast with a length the direction is normalized! That means your ray is 0.1 units long. But if you draw your ray with diagonal * length the drawn ray will be 4.743 units long since your direction is 47,43... long. I don't even understand your direction. It's forward but a bit to the right? Try diagonal.Normalize(); or .normalized.

var direction = Vector3(15,0,45);
var length = 0.1;

function Update () {
    var diagonal = transform.TransformDirection(direction);
    diagonal.Normalize();
    Debug.DrawRay(transform.position, diagonal * length,Color.green);

    if (Physics.Raycast(transform.position, diagonal,length)) {
        Debug.Log ("There is something in front of the object!");
    }
}

i think you forgot the hit :

var xDirection = 15;
var yDirection = 0;
var zDirection = 45; 
var length = 0.1;
var hit : RaycastHit;

function Update () {
var diagonal = transform.TransformDirection (Vector3(xDirection,yDirection,zDirection));
Debug.DrawRay(transform.position, diagonal * length,Color.green);


if (Physics.Raycast(transform.position, diagonal,hit,length)) {
    Debug.Log ("There is something in front of the object!");
}
}

hope it works

have you attached it to the right player? if you still can not get it to work send it to me to my e-mail and i can look at it for you. the project folder this is.

My e-mail:

Hotmail- gto_oni-eyes@hotmail.com

google:

Hummad.Nazir@gmail.com

i hope to hear from you :)

try my code:

 public  var RayCastHitDoor :float  = 5.0f;



// Update is called once per frame

function Update () {



var hit : RaycastHit ;



    Debug.DrawRay(transform.position, Vector3.forward * RayCastHitDoor, Color.red);

        if(Physics.Raycast(transform.position , Vector3.forward, hit, RayCastHitDoor))

    {

        Debug.DrawRay(transform.position,Vector3.forward * RayCastHitDoor , Color.green);

               if(hit.collider.gameObject.tag == "put your obj name in here "){


                   // then do something. in my case i have told the hit collider to play animation when it collides with the object that is tagged door

        hit.collider.gameObject.animation.Play("Door animation");   



        }



    }



}

instead of having animation you could have Destroy the object if you want to do that i would be like this:

     Destroy(hit..collider.gameObject);

and that should destroy the game object you can do what ever you like :)