create tween with actionscript

[skitzer]

Can someone please tell me how I can create a motion tween using actionscript?  I want a ball moving around in a circle (so oriented to a path).  I know about the Tween class, but I'm not sure how to do this using it. 

[Jorge Solis]

Ok, assuming your ball have an instance name of "ball", use:

angle = 0
centerX = 270
centerY = 200
radius = 100
speed = .1
this.onEnterFrame = function(){

ball._x = centerX + Math.cos(angle) * radius

ball._y = centerY + Math.sin(angle) * radius

angle += speed
}

Jorge

[winxalex]

Using onEnterFrame is the oldest and still much relabile method but u can got in mass pretty soon .
 Next method is using setInterval which is more OO,  like this:
 
angle = 0
centerX = 270
centerY = 200
radius = 100
speed = 10


function Move(){
   ball._x = centerX + Math.cos(angle) * radius
   ball._y = centerY + Math.sin(angle) * radius
   angle += 1
}


   setInterval(Move,speed);

Cos of extended need of tweenin( move,rotate, change color or...) MM has made Tween class
(imortant!!!  Move ur "ball" rotation center as u like ur radius to be)
speed=500;

import mx.transitions.Tween;
var myTween:Tween = new Tween(ball, "_rotation", mx.transitions.easing.None.easeNone,0,360, speed, false);
myTween.onMotionFinished = function() {
    trace("finished")
   myTween.start();
};

    myTween.start();

[skitzer]

Thanks to both of you. 

Can you help me figure out how to do this using an oval?  I have an oval on the screen and I want the ball to move along it.........

[Jorge Solis]

Use different radius for _x and _y

Jorge

[skitzer]

Merci Jorge.