Question

I have a function that adds an item to a random location to a grid (this is done on a timer event) and in this function i have a check that sees if the item hits the player. and if it does it calls the function. however it gives me the error when i call that function again. it might be because the function is a (event:TimerEvent)?

below is the function

 private function placeFood(event:TimerEvent = null):void{   
        var rndI:uint = Math.floor(Math.random() * DIM);  //sets a random integer based on the the floor
        var rndJ:uint = Math.floor(Math.random() * DIM);

        var rndX:Number = grid[rndI][rndJ].x; // sets a grid position for the food item to go
        var rndY:Number = grid[rndI][rndJ].y;

        if(_foodMap[int(rndX)] == null){
         _foodMap[rndX] = [];
        }

        if(_foodMap[int(rndX)][int(rndY)] == null){
         _foodMap[rndX][rndY] = food;
        }




        food = makeItem(Math.random() * 0xFFFFFF);// random color
        food.x = rndX;
        food.y = rndY;


        addChild(food); //adds the food to the board


        for (var i:uint = 0; i < snake.length; i++){
            if (rndY == snake[i].y && rndX == snake[i].x){ 
                placeFood();
            }
        } 
        }

Answer 1

If you call the function manually without the TimerEvent which the function is expecting you will get the error. So you need to define that the param’s default value is null:

private function placeFood(event:TimerEvent = null):void {
    //code
}

For the food map create the multidimensional array which will contains the references to foods.

private var _foodMap:Array = [];

Then in the place when you add the food then also add it to the food map like i did below so you could check if the location where the snake’s head is is empty.

if(_foodMap[int(rndX)] == null){
    _foodMap[rndX] = [];
}

if(_foodMap[int(rndX)][int(rndY)] == null){
    _foodMap[rndX][rndY] = food;
}

Then if both _foodMap[int(snakesHeadX)] == null and _foodMap[int(snakesHeadX)][int(snakesHeadY)] == null then it means the location of snake’s head is empty.