import flash.events.Event;

//-------------------
var vy:Number = 0;
var gravity:Number = 2;
var inAir:Boolean = true;
var jumping:Boolean = false;
var platforms:Array = new Array(platform1, platform2, platform3, platform4, platform5, platform6, platform7);
//-------------------

stage.addEventListener(Event.ENTER_FRAME, tick);

function tick(e:Event)
{
    vy += gravity;

    //if hero is in the air apply gravity
    if (inAir)
    {
        hero.y += vy;
    }
    //set terminal velocity - this is to prevent hero falling through platforms.
    if (vy < 15)
    {
        vy = 15;
    }

    //loop function for platforms
    for (var i:int = 0; i < platforms.length; i++)
    {
        //perform collsion check with platforms
        if (platforms[i].hitTestPoint(hero.x, hero.y, true))
        {
            hero.y = platforms[i].y; //set hero's point of reference to platforms
            vy = 0; //disable gravity for hero when on a platform
            jumping = false;
            inAir = false;
            break;
        }
        else
        {
            inAir = true
        }
    }
}