asked on

Changing the alpha of an instance in AS3

In Actionscript, I have created a For Loop to create six instances of a movie clip. How can I change the alpha of each instance to be less than the instance before it?

var _boarder:mcBoarder;
var _boarderX:Number = 133;
var _boarderY:Number = 267;
var _boarderR:Number = 0;

for(var i:Number = 0; i < 6; i++)
{
	_boarder = new mcBoarder();
	addChild(_boarder);
	_boarder.x = _boarderX;
	_boarder.y = _boarderY;
	_boarder.rotation = _boarderR;
	_boarderX += 60;
	_boarderY -= 60;
	_boarderR -= 45;
}

Open in new window

ASKER CERTIFIED SOLUTION

sjklein42

membership

This solution is only available to members.

To access this solution, you must be a member of Experts Exchange.

Start Free Trial

MrJiggyHill

ASKER

Unfortunately not. The alpha didn't change for each instance.

sjklein42

I think the "alpha" property may actually have an underscore, as in _boarder._alpha

Sorry 'bout that.

MrJiggyHill

ASKER

No, I got compiler errors doing ._alpha

sjklein42

Ok. Go back to the original. I had a typo (10 instead of 100). Should read like this:

var _deltaAlpha = 100/ _frameCount ;

SOLUTION

deepanjandas

membership

This solution is only available to members.

To access this solution, you must be a member of Experts Exchange.

Start Free Trial

MrJiggyHill

ASKER

still no change in the alpha

MrJiggyHill

ASKER

Ah - that worked deepanjandas! The alpha is now changing.

Thank you guys very much!

sjklein42

deepanjandas is right. Corrected (and simplified) code.

var _boarder:mcBoarder;
var _boarderX:Number = 133;
var _boarderY:Number = 267;
var _boarderR:Number = 0;

var _frameCount = 6;
for(var i:Number = 0; i <  _frameCount ; i++)
{
      _boarder = new mcBoarder();
      addChild(_boarder);
      _boarder.x = _boarderX;
      _boarder.y = _boarderY;
      _boarder.rotation = _boarderR;
      _boarder.alpha = 1.0 * ( _frameCount - i ) / _frameCount;
      _boarderX += 60;
      _boarderY -= 60;
      _boarderR -= 45;
}

Open in new window

deepanjandas

Try this for alpha:

var frameCount:int = 6;
var baseAlpha:Number = 1/_frameCount;

for(var i:Number = _frameCount; i > 0; i--)
{
      _boarder = new mcBoarder();
      addChild(_boarder);

      _boarder.x = _boarderX;
      _boarder.y = _boarderY;
      _boarder.rotation = _boarderR;

      _boarder.alpha = baseAlpha * i;
      else _boarder.alpha = _prevBoarder.alpha - _deltaAlpha;

      _boarderX += 60;
      _boarderY -= 60;
      _boarderR -= 45;
      _prevBoarder = _boarder;
}

Open in new window

Warm Regards
Deepanjan Das