Rotate object via script like in editor

Hello,
I currently have trouble rotating object(with all parented objects). I want same rotation like in editor, just using script.
I want to set rotation on y=90, but when I do the object position change, but not in the inspector(just visual). And that’s my problem, so I just want to change rotation, and object should stay in place.

Like this:
http://videobam.com/VgKrn
As you can see when I rotate in editor the rotation and position change. But via script just rotation change, moving object away from its original position.

Note: The object I want to rotate, I created using script, and then I attached some cubes as parent.

-Thanks

First, the object position reported in the Inspector is the local position. It is relative to the parent. So you will only get a position of (0,0,0), if the object is in the same position as the parent.

There are a few things I’m still fuzzy about in your questions. Here is a guess at some sample code. It uses a Bounds to calculate the center point of all the game objects based on the pivot point of all the objects in the collection. It will work well if all the objects are approximately the same size and there are no empty game objects in the collection. If you have objects of significantly different sizes, or if you have empty game object in your parented/childed set of objects, then you will need to do some additional work.

Start with a new scene. Build a collection of objects sharing parent/child relationships. Put this script on any object in the collection.

#pragma strict

var pivot : Vector3;
var speed : float = 45.0;

function Start() {
	var bounds : Bounds;
	bounds.center = transform.position;
	
	var transforms = transform.root.GetComponentsInChildren(Transform);
	for (var trans : Transform in transforms) {
		bounds.Encapsulate(trans.position);
	}
	pivot = bounds.center;
}

function Update() {
	if (Input.GetKey(KeyCode.LeftArrow)) {
		transform.root.RotateAround(pivot, Vector3.up, Time.deltaTime * speed);
	}
	if (Input.GetKey(KeyCode.RightArrow)) {
		transform.root.RotateAround(pivot, Vector3.down, Time.deltaTime * speed);
	}
	if (Input.GetKey(KeyCode.UpArrow)) {
		transform.root.RotateAround(pivot, Vector3.right, Time.deltaTime * speed);
	}
	if (Input.GetKey(KeyCode.DownArrow)) {
		transform.root.RotateAround(pivot, Vector3.left, Time.deltaTime * speed);
	}
}