Question

I’m trying to distribute 3 objects randomly on my stage but it’s not working. My movie is 800×800.

function makeRock():void{
    var tempRock:MovieClip;

    for(var i:Number = 1; i < 3; i++){
        tempRock = new Rock();
        tempRock.x = Math.round(800);
        tempRock.y = Math.round(-800);
        addChild(tempRock);
    }
}

What am I doing wrong?

Answer 1

Replace Math.round(800); with Math.random()*800;

function makeRock():void
{
    var tempRock:MovieClip;

    var i:uint = 0;
    for(i; i < 3; i++)
    {
        tempRock = new Rock();

        tempRock.x = Math.random()*800;
        tempRock.y = Math.random()*800;

        addChild(tempRock);
    }
}

Math.round(800) is just returning 800.

Math.random() returns a random number between 0 and 1, which you can multiply by 800 to get a random result of 0-800. A good note to make is that Math.random() never actually returns 1.0. Just everything from 0 up to 1.

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Further reading:

As a side note: this makes it simple to return a random element from an array; because you’re never getting 1 you can cast the result of Math.random()*array.length to uint() and always be within the boundaries of the array length.

eg.

var ar:Array = [1,2,"hello",4,5,6,7,8,9,0];

var randomElement:Object = ar[uint(Math.random()*ar.length)];
trace(randomElement);