Not able to fire projectiles at mouse position

Questions & Answers
1

Hey,

I’m trying to add a simple little system that shoots projectiles to the mouses location on click. I’ve it added and it’s shooting projectiles like I want it to, just not at the right direction. It doesn’t matter where my mouse is, if my character is on the right side of the scene, the projectiles will shoot left and if it’s on the left side, you guessed it - projectiles will fire away to the right.

Any idea what could be causing this? Here’s the relevant function.

 void Shoot () {
         if (Input.GetMouseButtonDown(0)) {
         Vector2 mousePos = new Vector2 (Camera.main.ScreenToWorldPoint(Input.mousePosition).x, Camera.main.ScreenToWorldPoint(Input.mousePosition).y);
         Vector2 myPos = new Vector2(transform.position.x,transform.position.y);
         Vector2 direction = mousePos - myPos;
         direction.Normalize();
         Quaternion rotation = Quaternion.Euler( 0, 0, Mathf.Atan2 ( direction.y, direction.x ) * Mathf.Rad2Deg);
         GameObject projectile = (GameObject)Instantiate( projectilePrefab, firePoint.position, rotation);
         projectile.GetComponent<Rigidbody2D>().velocity = direction * speed;
        }
	}
2

Try this

  void Shoot ()
  {
	if (Input.GetMouseButtonDown(0))
	{
		  Vector2 mousePos = Camera.main.ScreenToWorldPoint(Input.mousePosition);
		  Vector2 myPos = (Vector2)transform.position;
		  Vector2 direction = mousePos - myPos;
		  direction.Normalize();
		  float angle =  Mathf.Atan2 ( direction.y, direction.x ) * Mathf.Rad2Deg;
		  GameObject projectile = (GameObject)Instantiate( projectilePrefab);
		  projectile.transform.position = firePoint.position;
		  projectile.transform.Rotate (0, angle, 0);
		  projectile.GetComponent<Rigidbody2D>().velocity = direction * speed;
	}
}
3

I think I have a better solution

Declare public float angleOffsetInDegrees, change it in the inspector to get the desired rotation in degrees.

void Shoot() {
    if (Input.GetMouseButtonDown(0)) {
        Vector2 mousePos = Camera.main.ScreenToWorldPoint(Input.mousePosition); //Mouse position to world position
        Vector2 myPos = new Vector2(transform.position.x, transform.position.y);
  
        //Calculate direction in quaternion
        Quaternion targetQuaternion = Quaternion.Euler(Quaternion.LookRotation(Vector3.forward, mousePos - myPos).eulerAngles + new Vector3(0f, 0f, angleOffsetInDegrees));
  
        //Calculate direction in Vec3
        Vector3 direction = new Vector3(Mathf.Sin(-targetQuaternion.eulerAngles.z * Mathf.Deg2Rad), Mathf.Cos(targetQuaternion.eulerAngles.z * Mathf.Deg2Rad), 0f);
        direction.Normalize();
  
        //Instantiate
        GameObject projectile = (GameObject)Instantiate(projectilePrefab, firePoint.position, targetQuaternion);
        projectile.GetComponent<Rigidbody2D>().velocity = direction * speed;
    }
}

First I calculate the Quaternion setting the foward vector as the pivot for the rotation, and then the Vector3 using the Sin and Cos functions to get the corresponding angle.