Unity2D Enemy Patrol, weird sprite rotation

Question

Needed help here, I've been following this tutorial about Enemy Patrolling, https://www.youtube.com/watch?v=KKU3ejp0Alg

The tutorial tell us to set 2 Empty Game Objects and the coordinates so the sprite will walk from one direction to another, the walking does working, however the rotation of the sprite became really weird, the 'Worm' sprite is suppose to move left and right now it change into facing upward Please look at this image,

When moving from left to right

When moving from right to left

public Transform[] patrolPoints;
public float speed;
Transform currentPatrolPoint;
int currentPatrolIndex;

// Use this for initialization
void Start()
{
    currentPatrolIndex = 0;
    currentPatrolPoint = patrolPoints[currentPatrolIndex];
}

// Update is called once per frame
void Update()
{
    transform.Translate(Vector3.up * Time.deltaTime * speed);

    if (Vector3.Distance(transform.position, currentPatrolPoint.position) < .1f) {
        if (currentPatrolIndex + 1 < patrolPoints.Length)
            currentPatrolIndex++;
        else
            currentPatrolIndex = 0;
        currentPatrolPoint = patrolPoints[currentPatrolIndex];
    }

    Vector3 patrolPointDir = currentPatrolPoint.position - transform.position;
    float angle = Mathf.Atan2(patrolPointDir.y, patrolPointDir.x) * Mathf.Rad2Deg - 90f;

    Quaternion q = Quaternion.AngleAxis(angle, Vector3.forward);
    transform.rotation = Quaternion.RotateTowards(transform.rotation, q, 180f);

}

This is the code

Thank you

Instead of rotate, set the local scale x value to -1 or minus what ever the positive is. Surprisingly this works. — Catwood
swap the last 2 lines for transform.localScale = new Vector2(-1,1); to flip it. — Catwood

Martin Dinh Martin Dinh · Accepted Answer · 2017-07-19T12:14:01

You can pass the optional parameter Space.World to your translation to move your object relative to world space instead of object space. That should prevent your object from rotating.

transform.Translate(Vector3.up * Time.deltaTime * speed, Space.World);

You can read more about it in the documentation.

Unity2D Enemy Patrol, weird sprite rotation

2 Answers