ColorTransform removes shadow - actionscript-3

Question

I've got movie clip on stage that has shadow filter.
When I apply ColorTransform to that movie clip, the shadow removes.
var ct:ColorTransform = new ColorTransform;
ct.color = 0x99CC00;
lamp.transform.colorTransform = ct;
How to save shadow?

Answer 1

The idea is to
save the filters (shadow) of your clip lamp,
apply the transformation,
put the clip in a master clip and
re-apply the filters to this untransformed parent.
code:
var lampFilters:Array = lamp.filters.slice(); //save filters
lamp.filters = []; //empty filters
var ct:ColorTransform = new ColorTransform();
ct.color = 0x99CC00;
lamp.transform.colorTransform = ct; //apply your transformation
var superLamp:Sprite = new Sprite();
superLamp.addChild(lamp); //nest the clip
addChild(superLamp);
superLamp.filters = lampFilters; //re-apply the filters

Answer 2

ColorTransform will transform the entire MovieClip, unfortunately, the filter is included. I suggest you layer lamp and apply the transform to the top most layer keeping the bottom layer (shadow) untouched.
Test example:
var ball:Sprite = new Sprite();
ball.graphics.beginFill(0x00FF00, 1);
ball.graphics.drawCircle(50, 50, 50);
ball.graphics.endFill();
ball.filters = [new DropShadowFilter()]; //default black
ball.addEventListener(MouseEvent.CLICK, changeColor);
addChild(ball);
//...
private function changeColor(evt:MouseEvent):void {
var ball:Sprite = evt.target as Sprite;
var ct:ColorTransform = new ColorTransform();
ct.color = 0x99CC00; // green-ish
ball.transform.colorTransform = ct;
ball.filters = [new DropShadowFilter(4, 45, 0xFFFFFF)]; //now white
}
Even with the shadow filter reapplied you can see it's still going to be green-ish as set by the transform.

Answer 3

You should use nested display objects to achieve this...
for instance you can create a movieclip within another movieclip. apply the colortransform to inner movie clip and apply the shadow to outer movie clip. works like a charm for me :)

Answer 4

Here is an alternate method that does not require a parent object. You basically use an AdjustColor and ColorMatrix to change the color instead of a ColorTransform.
Note:If you are using an IDE other than Flash, like Flex or FlashDevelop, you will need to include flash.swc into your library from 'Common/Configuration/ActionScript 3.0/libs/flash.swc' for the fl.motion.AdjustColor package/class. You can also Google the swc.
var mc:Sprite = new Sprite();
mc.graphics.beginFill(0xFF0000);
mc.graphics.drawCircle(100, 100, 100);
mc.graphics.endFill();
addChild(mc);
// White out the entire shape first
var whiteAC:AdjustColor = new AdjustColor();
whiteAC.brightness = 100;
whiteAC.contrast = 100;
whiteAC.saturation = -100;
whiteAC.hue = 0;
var whiteMatrix:Array = whiteAC.CalculateFinalFlatArray();
var whiteCMF:ColorMatrixFilter = new ColorMatrixFilter(whiteMatrix);
// Now use ColorMatrixFilter to change color
var colorMatrix:Array = hexToMatrix(0x0000FF);
var colorCMF:ColorMatrixFilter = new ColorMatrixFilter(colorMatrix);
// Create Drop Shadow
var myDropShadow:DropShadowFilter = new DropShadow();
mc.filters = [whiteCMF, colorCMF, myDropShadow];
function hexToMatrix ( hex:uint, alpha:Number = 1 )
{
var r:Number = ((hex & 0xFF0000) >> 16);
var g:Number = ((hex & 0x00FF00) >> 8);
var b:Number = ((hex & 0x0000FF));
var matrix:Array = [];
matrix = matrix.concat([r, 0, 0, 0, 0]); // red
matrix = matrix.concat([0, g, 0, 0, 0]); // green
matrix = matrix.concat([0, 0, b, 0, 0]); // blue
matrix = matrix.concat([0, 0, 0, alpha, 0]); // alpha
return matrix;
}