gistfile1.txt

void Update ()
    {
        Vector2 mouseDir = Camera.main.ScreenToWorldPoint(Input.mousePosition) - (transform.position);//vector to mouse position
        float curDir = SignCrossZ(curForward, mouseDir); //angle to mouse
        float curDelta = curDir * speed * Time.deltaTime; //angle change speed
        Vector2 newForward = Quaternion.Euler(0, 0, curDelta) * curForward; // new projection

        if (SignCrossZ(curForward, newForward) != SignCrossZ(newForward, mouseDir)) {
            // went wrong direction, change projection            
            curForward = Quaternion.Euler(0, 0, Vector2.SignedAngle(Vector2.up, mouseDir)) *  Vector2.up;
        }
        else{//right direction
            curForward = newForward;
        }
        
        //дебуг
        //lrCurrent.SetPosition(0, transform.position);
        //lrCurrent.SetPosition(1, (Vector2)transform.position+curForward * 4);

        //lrTarget.SetPosition(0, transform.position + Vector3.forward);
        //lrTarget.SetPosition(1, transform.position + Quaternion.Euler(0, 0, Vector2.SignedAngle(Vector2.up, mouseDir)) * Vector2.up * 5 + Vector3.forward);

        // sets rotation       
        var angle = Mathf.Atan2(curForward.y, curForward.x) * Mathf.Rad2Deg - 90f;
        transform.rotation = Quaternion.AngleAxis(angle, Vector3.forward);
    }