How to move a GameObject from his position to a xyz position.

How to move (translation or else) a GameObject from his position to a xyz (Vector3)?

[EDIT] Have a cube/GO that I want to move to a specific location on the terrain slowly, using Time.deltaTime . I don't want it to suddenly appear at that position.

Could you be more specific? In scripting you normally move a non-physics GameObject with the methods defined on transform. So something like:

transform.position = Vector3(10, 10, 10);

but I doubt that's what you're after.

EDIT as the next poster says, something like Vector3.Lerp would do the trick complete code in Javascript:

var endPoint : Vector3;
var duration : float = 1.0;

private var startPoint : Vector3;
private var startTime : float;

function Start() {
    startPoint = transform.position;
    startTime = Time.time;
}

function Update () {
    transform.position = Vector3.Lerp(startPoint, endPoint, (Time.time - startTime) / duration);
}

The easy, built-in way is to use a Lerp function. The Lerp function takes a start and end argument, and a floating point number which you can think of as being the percentage complete of the movement. Usually this argument is based on time. So at time=0.0 Lerp will return the first number, at 1.0 it will return the 2nd number, and for numbers less than 1.0 it will return some number in-between.

The Vector3 class has a Lerp function, so you can use that to calculate points between the start and end positions.

That just leaves the question of what to pass in for the last argument. If you store the starting time (startTime = Time.time) right when the movement starts, you can pass in t = (Time.time - startTime) for the third argument. This would finish the movement after one second. To make it last twice as long, multiply t by 0.5. To make it twice as fast, multiple t by 2.

You end up with something like: transform.position = Vector3.Lerp(startPos, endPos, speed * (Time.time - startTime)); You would typically do this in your object's Update function. Every frame your object moves a bit further along.

So that's the basic approach. For fancier movement, instead of linear interpolation (Lerp) you could instead use a function that starts slow ("ease-in") and/or slows down at the end ("ease-out"). The Unity wiki has some functions that perform these kinds of effects.

What if I want the user to click on an object in 3D space and then the camera moves to a particular location? Where would I put this code?

I don't think that you need it anymore , but it would be something like this:

Create a static boolean variable with its value false (static var myBool : boolean = false;) Write a code : when you click on that object myBool will get the value true and if myBool is true then Lerp the position...

script on the camera (CameraScript.js)

static var myBool:boolean=false;
var speed = 1.5;

       function FixedUpdate()
       {
        if(myBool == true)
          transform.position = Vector3.Lerp(transform.position, waypoint.position, speed /150);
       }

the script on the object (you want the user to click):

private var ok:boolean=false;

function OnMouseEnter() 
{
   ok=true;
}

function OnMouseEnter() 
{
   ok=false;
}

function Update()
{
   if(ok && Input.GetKey("mouse 0"))
      CameraScript.myBool=true;
}

of course you can use:

function OnMouseOver()
{
    if(Input.GetKey("mouse 0"))
        CameraScript.myBool=true;
}

I wrote both of them cuz' of some bad experiences in the past ...