How to move forward an object in Unity?

Question

I made a game object and attached a script to it. I need to rotate and move the object in a straight line, depending on the rotation. I made a turn, but I have problems with movement. Any solutions?

    //Rotation
    if (Input.GetAxis("Rotation") > 0) {
        transform.Rotate(Vector3.back, turnSpeed * Time.deltaTime);
        
    }
    else if (Input.GetAxis("Rotation") < 0)
    {
        transform.Rotate(Vector3.back, -turnSpeed * Time.deltaTime);
        
    }

    //Velocity
    if (Input.GetAxis("Thrust") != 0) {
            rb.AddForce(Vector3.forward * Time.deltaTime * Speed);
        }
    else if (Input.GetAxis("Thrust") <= 0.1f){
        rb.velocity = new Vector2(0, 0);
    }

Answer 1

Rigidbody.AddForce applies the vector as force in world space. So, you need to give it a vector that is in the world space direction of the transform's forward. Luckily, that's as simple as usingtransform.forward , transform.up , or transform.right or a negation of one of them instead of Vector3.forward :

//Rotation
if (Input.GetAxis("Rotation") > 0) {
    transform.Rotate(Vector3.back, turnSpeed * Time.deltaTime);
    
}
else if (Input.GetAxis("Rotation") < 0)
{
    transform.Rotate(Vector3.back, -turnSpeed * Time.deltaTime);
    
}

//Velocity
if (Input.GetAxis("Thrust") != 0) {
        Vector3 frontDirection;
        
        // probably one of these for a 2D game:
        frontDirection = transform.right;
        //frontDirection = -transform.right;
        //frontDirection = transform.up;
        //frontDirection = -transform.up;

        rb.AddForce(frontDirection * Time.deltaTime * Speed);
    }
else if (Input.GetAxis("Thrust") <= 0.1f){
    rb.velocity = new Vector2(0, 0);
}