//method to keep objects within screen
        /// <summary>
        /// Ensures that object is within top and bottom bounds of the screen, targeted to be used with player object but can take any GameEntity object
        /// </summary>
        /// <param name="obj">Any GameEntity object to be checked and kept within top and bottom of screen</param>
        public void screenLimit(GameEntity obj)
        {
            if (obj.pos.Y <= 0 )                                         //at top wall
                obj.pos.Y = 0;                                           //if closer than the 0 that means Sprite would go outside, so reset

            if (obj.pos.Y >= (Game1.Instance.Window.ClientBounds.Height ))  //at bottom wall
                obj.pos.Y = (Game1.Instance.Window.ClientBounds.Height );  //reset if too close to bottom wall, same as other
        }
        //if enenmy hit by player Check
        /// <summary>
        /// Checks if the enemy was hit by player bullet, removes the enemy and bullet if so
        /// </summary>
        /// <param name="obj">Any GameEntity (enemy,comet,etc.) object to be checked</param>
        void enemyHit(GameEntity obj)
        {
            for (int i = 0; i < playerBullet.Count; ++i)        //for all player bullets
            {
                if (playerBullet[i].me.Intersects(obj.me))      //if player bullet intersects object currently checked
                {
                    score += obj.scoreGain;                     //increase score
                    enemyList.Remove(obj);                      //remove object(enemy only takes one shot

                    playerBullet.Remove(playerBullet[i]);       //remove bullet
                    --i;                                        //fix index
                }
            }
        }
        //checks if obj has passed by the left wall
        /// <summary>
        /// Checks if an enemy has passed by the player to the left and returns a boolean
        /// </summary>
        /// <param name="obj">Object that will be checked if it has passed by the player to the left</param>
        /// <returns></returns>
        public bool enemyPassed(GameEntity obj)
        {
            if (obj.pos.X <= -obj.Sprite.Width / 2)
                return true;

            return false;
        }