On key press, spawn a collider where my player is facing?

Question

I'm trying to create an attack mechanic to my player hero in my 2D Tower Defense game. When I press the Q button I want my hero to do an animation and spawn a temporary collider shaped as a cone at where the hero is looking at. If this collider collides with a GameObject called "Stone" it will decrease its hpValue with a script I made. If there is multiple Stones in the cone I want it to only effect one Stone, chosen either by random or/and closest to the hero.

How would I go about doing this and how can I detect the direction of where my hero is facing? This is my movement script:

public float speed;   //Movementspeed

Rigidbody2D rbody;

void Start () {

    rbody = GetComponentInChildren<Rigidbody2D> ();
    rbody.freezeRotation = true;
}

void FixedUpdate () {

    Vector2 movement_vector = new Vector2(Input.GetAxisRaw("Horizontal"), Input.GetAxisRaw("Vertical"));

    rbody.MovePosition (rbody.position + movement_vector * speed * Time.deltaTime);

}

A picture visualising what I mean:

Answer 1

To determine the cone you should create some variables like AttackLength, FieldOfViewAngke and get enemy component to determine enemy position

lookDirection = enemyPosition - player.transform.position;
lookDirection.y = 0;
attackDirection = Vector3.zero;
float angle = Vector3.Angle(lookDirection, transform.forward);

if (Physics.Raycast(enemyPosition, lookDirection, out hitInfo, AttackLength, layerMask))
{
    if (angle <= FieldOFViewAngle * 0.5f)
    {
     //action
    }
}

And instead of spawning collider you can go other way by tagging enemy or stone or whatever like "enemy" and add the check to second if-statement like

&&hitInfo.collider.gameObject.tag == "enemy"

To clarify: Green is player, red-enemy. lookDirection Vector is black, gotten from subtraction of playerPos from enemyPos; Yellow is your filed of view, e.g. 170 degrees; Blue is transform.forward Vector from the player; float angle = angle between Blue and Yellow; to check if the enemy is in the FOV, you check if this angle is less then the half of the FOV

Answer 2

To detect the direction that your player is facing you can use transform.forward as a vector3 value .