# Ball physics in AS3

**URL:** <https://forum.kirupa.com/t/ball-physics-in-as3/320038>\
**Category:** Uncategorized\
**Created:** [March 12, 2011, 2:29am UTC](https://forum.kirupa.com/t/ball-physics-in-as3/320038 "2011-03-12T02:29:20Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![faizi](https://avatars.discourse-cdn.com/v4/letter/f/b2d939/32.png) [@faizi](https://forum.kirupa.com/u/faizi)\
**Post date:** [March 12, 2011, 2:29am UTC](https://forum.kirupa.com/t/ball-physics-in-as3/320038/1 "2011-03-12T02:29:20Z")

</div>

ball physics in AS3 here is the code:-  
var dx:Number;  
var dy:Number;  
var gravity:Number;  
var dy\_decrement:Number;

ball.addEventListener(Event.ENTER\_FRAME,enter\_frame);  
init();

function init()  
{  
dx = 2.5;  
dy = -20;  
gravity = .5;  
dy\_decrement = dy;  
ball.x = ball.width;  
ball.y = stage.stageHeight-ball.height/2;  
}

function enter\_frame(e:Event)  
{

```
if(ball.y &gt; stage.stageHeight)
{
    ball.y = stage.stageHeight - ball.height;
    dy_decrement +=3 
    dy = dy_decrement;
}

else if(ball.x &gt; stage.stageWidth)
{
    init();
}

else
{
    dy+=gravity;
    ball.x += dx;
    ball.y += dy;
}

```

}