Script not function if mouse is on object

Questions & Answers
1

I have modified the mouse orbit script from standard assets to function when the left mouse button is down, but how do I make it function only if the mouse is NOT over a certain object in my scene? Here is the modified code:

var target : Transform;
var distance = 10.0;

var xSpeed = 250.0;
var ySpeed = 120.0;

var yMinLimit = -20;
var yMaxLimit = 80;

private var x = 0.0;
private var y = 0.0;

@script AddComponentMenu("Camera-Control/Mouse Orbit")

function Start () {
    var angles = transform.eulerAngles;
    x = angles.y;
    y = angles.x;

	// Make the rigid body not change rotation
   	if (rigidbody)
		rigidbody.freezeRotation = true;
}

function LateUpdate () {
if(Input.GetKey(KeyCode.Mouse0)){
    if (target) {
        x += Input.GetAxis("Mouse X") * xSpeed * 0.02;
        y -= Input.GetAxis("Mouse Y") * ySpeed * 0.02;
 		
 		y = ClampAngle(y, yMinLimit, yMaxLimit);
 		       
        var rotation = Quaternion.Euler(y, x, 0);
        var position = rotation * Vector3(0.0, 0.0, -distance) + target.position;
        
        transform.rotation = rotation;
        transform.position = position;
    }
}
}

static function ClampAngle (angle : float, min : float, max : float) {
	if (angle < -360)
		angle += 360;
	if (angle > 360)
		angle -= 360;
	return Mathf.Clamp (angle, min, max);
}
2

OnMouseEnter and OnMouseExit will tell you when the cursor is in front of an object with a collider (provided it doesn’t belong to the Ignore Raycast layer. Use these functions to set a flag and only perform your updates when the flag says so:

var isMouseOver : boolean = false;

function Start() {
    isMouseOver = false;
}

function OnMouseEnter() {
    isMouseOver = true;
}

function OnMouseExit(0 {
    isMouseOver = false;
}

function LateUpdate () {
    if(isMouseOver && Input.GetKey(KeyCode.Mouse0)){
// ... etc

Note that I don’t use UnityScript myself so the syntax might not be 100% correct. I also don’t know if there are any cases where the OnMouseEnter/Exit callbacks aren’t sent, which would break the toggling of the flag.