Unity Recipes - Look Toward Direction of Movement

p>The following C# script for Unity can be used to make an object look (turn smoothly) toward the direction it is being moved.

using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class MyController : MonoBehaviour
{
     private void Update()
     {
          smoothLookTowardDirectionOfMovement();
     }

     void smoothLookTowardDirectionOfMovement()
     {
          float moveHorizontal = moveHorizontal = Input.GetAxis("Horizontal");
          float moveVertical = moveVertical = Input.GetAxis("Vertical");
          Vector3 movement = new Vector3(moveHorizontal, 0.0f, moveVertical);
          if (moveHorizontal != 0 || moveVertical != 0)
          {
              transform.rotation = Quaternion.Slerp(transform.rotation, Quaternion.LookRotation(movement), 0.15F);
          }
     }
}

In line 19, Quaternion.Slerp takes three arguments: two quaternions and a float. It interpolates the rotation between the two quaternions with the speed of the given float value (0.0 is no movement while 1.0 is instant movement). The code interpolates the rotation between the current rotation (transform.rotation) and the movement rotation(Quaternion.LookRotation) with a speed of 0.15F. This gives the object a smooth turn instead of an instant turn. The if statement that wraps the code at line 17 keeps the object from instantly flipping or reverting direction when no inputs are being applied.

For instant (non-smooth) rotation, line 19 can be replaced with the following:

transform.rotation = Quaternion.LookRotation(movement);