I am having a projectile object which I want to spawn and move it along the cursor direction after some seconds.

Basically if I don't wait after spawning the projectile, then the movement is working great. But since I am waiting for some seconds before I move the projectile, It actually travels backward and hitting the player.

here is the code.

void crossHairPosition(){
if (Physics.Raycast(ray, out hit, 100f, layer_Mask))
        {
            Debug.DrawLine(firePoint.position, hit.point, Color.green);
            destination = hit.point;
            crossHairPrefab.transform.position = ray.GetPoint(10);
            crossHairPrefab.transform.LookAt(Camera.main.transform);
        }
        else {
            destination = ray.GetPoint(1000);
        }
}

void spawnProjectile(){
projectile=Instantiate(projectileObj,player.transform.position,Quaternion.identity);
StartCoroutine(waitforseconds(2));
}

IEnumerator waitforseconds(float time){
    
    yield return new WaitForSeconds(time);   
     moveProjectile();
    }
void moveProjectile(){
        Vector3 difference=destination - projectile.transform.position;
        float distance=difference.magnitude;
        Vector3 direction=difference/distance;
        direction.Normalize();
       
        projectileObj.GetComponent<Rigidbody>().velocity = direction * 10f;
}

CodePudding user response：

Just so the question has an answer, I'll write my comment out as a post. As there is an issue with delaying the direction calculation when firing the projectile, but no issue without a delay, cache the direction vector and pass it into the IEnumerator.

The code could look something like:

IEnumerator waitforseconds(float time)
{
    // calculate the direction before the wait
    Vector3 difference=destination - projectile.transform.position;
    float distance=difference.magnitude;
    Vector3 direction=difference/distance;
    direction.Normalize();
    
    yield return new WaitForSeconds(time);
    
    // pass in our pre-calculated direction vector
    moveProjectile(direction);
}

void moveProjectile(Vector3 direction)
{
    projectileObj.GetComponent<Rigidbody>().velocity = direction * 10f;
}