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I am making a top-down shooter in Unity (following a Brackeys tutorial for the top-down shooting mechanic). When I press the left mouse button a bullet prefab spawns, as it should, however there is no force applied to the bullet. As you will be able to see in the code, I have applied force to the bullet, I am not sure why it won't work. Any ideas guys? Thank you in advance!

This is my shooting script:

#region Variables
// floats
private float bulletForce = 130f;

// bools

// rigidbodies
private Rigidbody2D rb = null;

// transforms
public Transform firePoint = null;

// game objects
public GameObject bulletPrefab = null;
private GameObject bullet = null;
#endregion
#region Awake
// called before the script is initialised
private void Awake()
{

}
#endregion
#region Update
// called ever frame - used for checking for input
private void Update()
{
    if (Input.GetButtonDown("Fire1"))
    {
        Shoot();
    }
}
#endregion
#region FixedUpdate
// called at a fixed time - every 0.2 seconds - used for physics
private void FixedUpdate()
{

}
#endregion
#region Method - Shoot
// method to spawn bullet prefab and shoot bullet
private void Shoot()
{
    // spawn the bullet prefab at the position of fire point and rotate the prefab bullet to match the rotation of the player - name this newly created bullet by storing it in variable named bullet
    bullet = Instantiate(bulletPrefab, firePoint.position, firePoint.rotation);
    // store rigidbody on bullet game object in rb variable
    rb = bullet.GetComponent<Rigidbody2D>();
    // add force to the bullet - impulse makes the bullet fly straight away - also in this line of code i get the angle offset variable from the player controller script
    rb.AddForce((firePoint.forward * gameObject.GetComponent<PlayerController>().angleOffset) *  bulletForce, ForceMode2D.Impulse);
}
#endregion

}

This is my PlayerController script:

#region Variables
// floats
private float moveSpeed = 10f;
private float angle = 0f;
public float angleOffset = 270f;

// bools

// rigidbodies
private Rigidbody2D rb = null;

// vector2s
private Vector2 movement = Vector2.zero;
private Vector2 mousePos = Vector2.zero;
private Vector2 lookDirection = Vector2.zero;

// cameras
public Camera cam = null;
#endregion
#region Awake
// called before the script is initialised
private void Awake()
{
    // store rigidbody component in rb variable
    rb = GetComponent<Rigidbody2D>();
}
#endregion
#region Update
// called ever frame - used for checking for input
private void Update()
{
    // listen for horizontal input from the player - a and d or left arrow key and right arrow key
    movement.x = Input.GetAxis("Horizontal");
    // listen for vertical input from the player - w and s or up arrow key and down arrow key
    movement.y = Input.GetAxis("Vertical");

    // find the mouse position, then convert the pixel position to world point and store that in a variable
    mousePos = cam.ScreenToWorldPoint(Input.mousePosition);
}
#endregion
#region FixedUpdate
// called at a fixed time - every 0.2 seconds - used for physics
private void FixedUpdate()
{
    // move the player to the desired position - fixed delta time happens every time fixed update is called
    rb.MovePosition(rb.position + movement * moveSpeed * Time.fixedDeltaTime);

    // find the direction the player needs to look by subtracting two vectors from each other
    lookDirection = mousePos - rb.position;
    // this finds the angle needed to calculate where the player should look then converts it to degrees
    angle = Mathf.Atan2(lookDirection.y, lookDirection.x) * Mathf.Rad2Deg - angleOffset;
    // rotate the player using the above maths
    rb.rotation = angle;
}
#endregion

}

enter image description here The bullet just spawns Infront of the sprite and doesn't move.

enter image description here

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  • \$\begingroup\$ Can you write a "Console.WriteLine" statement inside the method Shoot(), FixedUpdate(), and Update() to see if these methods are called ? \$\endgroup\$ Nov 12, 2023 at 23:19
  • \$\begingroup\$ Thanks for getting in touch, I used a Debug.Log statement and yes, the method is called. \$\endgroup\$ Nov 13, 2023 at 6:41
  • \$\begingroup\$ According to Newton's_laws_of_motion, When the force is applied for a very short time(one frame), it has little effect on the object's speed. So my first attempt would be to set the velocity directly on the bullet instead of applying force. \$\endgroup\$
    – Mangata
    Nov 13, 2023 at 8:55
  • 1
    \$\begingroup\$ @Mangata note that they're using ForceMode2D.Impulse which accomplishes an instantaneous change in momentum, similar to setting velocity. I agree setting velocity directly is simpler, but the current method is not dependent on the time interval of the physics tick. \$\endgroup\$
    – DMGregory
    Nov 13, 2023 at 11:49

1 Answer 1

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It should have been .up instead of forward, because forward is for 3D. Then *-1 because I want it to go in the opposite direction.

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