Quaternion.Lerp usage...

Questions & Answers
1

Hi. I am trying to use have an object rotate from (0,0,0) to (0,0,90) in two seconds. When I try this bit of code, I get the following error:

‘UnityEngine.Vector3’ to
‘UnityEngine.Transform’.

What am I missing? Thanks

var from : Transform;
var to : Transform;
var speed = 0.1;
function Update () {
    transform.rotation =
      Quaternion.Lerp (from.rotation, to.rotation, Time.time * speed);

	to  =transform.eulerAngles = Vector3(0, 0,  0);
	from=transform.eulerAngles = Vector3(0, 0, 90);

}

2

You’re assigning transform.eulerAngles (a Vector3) to a Transform (to and from) - that’s what’s causing the error. In order to rotate at constant speed, the best solution is to use Slerp in a coroutine, like this (script attached to the rotating object):

var rotating = false;

function RotateZ(angle: float, duration: float){
  // don't start another rotation while the previous has not ended
  if (rotating) return;
  rotating = true; // set the flag to block other RotateZ calls
  var oldRot = transform.rotation;
  // calculate the new rotation - current rotation * desired rotation:
  var newRot = Quaternion.Euler(0, 0, angle) * oldRot;
  var t: float = 0; // t is the control variable
  while (t < 1){
    t += Time.deltaTime/duration;
    transform.rotation = Quaternion.Slerp(oldRot, newRot, t);
    yield; // return and resume here next frame
  }
  rotating = false; // rotation ended;
}

Call the function RotateZ(90, 2) and the object will rotate 90 degrees around Z in exactly 2 seconds.

3

Try:

		var from : Transform;
		var to : Transform;
		
		function Start () {
		to.transform.eulerAngles = Vector3(0, 0,  0);
		from.transform.eulerAngles = Vector3(0, 0, 90);
		}
		
		function Update () {

		var speed = 0.1;
		
		transform.rotation =
		      Quaternion.Lerp (from.rotation, to.rotation, Time.time * speed);
		
		}

The error was with your assignment of to and from as seen in the start()