# Mouse wheel zoom

how can i change a variable smoothly with the mouse wheel (maybe using mathf.Lerp or some kind of interpolation)

I need to change the distance var.

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;

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 (target && Input.GetKey(KeyCode.Mouse1)) {
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);
}
``````

It’s hard to find the correct syntax for scrollwheel. It’s not in Input or GetAxis :

``````Input.GetAxis("Mouse ScrollWheel")
``````

``````var distanceMin : float = 3.0;
var distanceMax : float = 10.0;
var zoomSpeed : float = 2.0;

// in function
distance = Mathf.Clamp( distance + Input.GetAxis("Mouse ScrollWheel") * zoomSpeed, distanceMin, distanceMax );
``````