How to rotate an object to face the direction it is slerping?

Questions & Answers
1

Currently I’m writing a space station game that has ships flying around the station, following a set of waypoints, and then ultimately ending up at the front of the station ready to perform the next, yet-to-be-written docking function.

As of now, I’m able to have the object follow the waypoints by slerping between them, but I wanted to have the ships facing the direction they are moving. I was able to use transform.LookAt() to make the object face the next waypoint, however this results in a hard snap in the direction of the next waypoint.

I assume I’ll have to use an additional slerping function to do this but I’m not sure how.

This is the code that I’m using for my MoveShip script
using UnityEngine;
using System.Collections;

public class MoveShip : MonoBehaviour {

    [HideInInspector]
    public GameObject[] waypoints;
    private int currentWaypoint = 0;
    private float lastWaypointSwitchTime;
    public float speed = 1.0f;

    public Vector3 Velocity;
    public Vector3 MoveDirection;
    public Vector3 Target;
    public Vector3 endPointDirection;
    // Use this for initialization
	void Start () {
        lastWaypointSwitchTime = Time.time;
	}
	
	// Update is called once per frame
	void Update () {

        Vector3 startPosition = waypoints[currentWaypoint].transform.position;
        Vector3 endPosition = waypoints[currentWaypoint + 1].transform.position;
        
        float pathLength = Vector3.Distance(startPosition, endPosition);
        float totalTimeForPath = pathLength / speed;
        float currentTimeOnPath = Time.time - lastWaypointSwitchTime;
        gameObject.transform.position = Vector3.Slerp(startPosition, endPosition, currentTimeOnPath / totalTimeForPath);
                
        if (gameObject.transform.position.Equals(endPosition))
        {
            
            if (currentWaypoint < waypoints.Length - 2)
            {
                
                currentWaypoint++;
                lastWaypointSwitchTime = Time.time;

               
            }
            else
            {
            
                return;
            } 
            
        }
        
        transform.LookAt(endPosition);
        //gameObject.transform.position = Vector3.Slerp(startPosition, endPosition, currentTimeOnPath / totalTimeForPath);
        //transform.rotation = Quaternion.Slerp(transform.rotation, _lookRotation, currentTimeOnPath / totalTimeForPath);
        

	}
}
2

Quaternion.Lerp can help you here. Just put this code in Update and the ship will always look at it’s “target”:

//Get the vector between the transform and the target, calculate the rotation needed 
//to "look at" it, and interpolate from the current rotation to the desired one
Vector3 relativePos = target.position - transform.position;
Quaternion rotation = Quaternion.LookRotation(relativePos);
transform.rotation = Quaternion.Lerp(transform.rotation, 
	                                     rotation, Time.deltaTime * RotationSpeed);