Smudge Tool #1

[SWF(backgroundColor = 0xCCCCCC)]
var canvas:BitmapData = new BitmapData(stage.stageWidth,stage.stageHeight,true, 0xFFFFFFFF);
addChild(new Bitmap(canvas));

var loader:Loader = new Loader();
loader.load(new URLRequest("https://actionsnippet.com/wp-content/chair.jpg"));
loader.contentLoaderInfo.addEventListener(Event.COMPLETE, onComplete);
function onComplete(evt:Event):void{
	canvas.draw(loader);
}

var brush:Shape = new Shape();
var diameter:Number = 120;
var radius:Number = diameter / 2;
var matrix:Matrix = new Matrix();

var brushAlpha:BitmapData = new BitmapData(diameter, diameter, true, 0x00000000);
drawRadial();
brushAlpha.draw(brush);

var xp:Number = 0, yp:Number = 0, px:Number = 0, py:Number = 0;
var dx:Number, dy:Number;

stage.addEventListener(MouseEvent.MOUSE_MOVE, onLoop);
function onLoop(evt:Event):void {
	xp = mouseX - radius;
	yp = mouseY - radius;
	dx = xp - px;
	dy = yp - py;
	canvas.copyPixels(canvas,
					new Rectangle(px, py, diameter, diameter),
					new Point(xp, yp), brushAlpha, new Point(0,0), true);
	px = xp;
	py = yp
}

function drawRadial():void{
	matrix.createGradientBox(diameter, diameter, 0, 0, 0);
	with (brush.graphics){
		beginGradientFill(GradientType.RADIAL, [0xFFFFFF, 0xFFFFFF], [1,0], [0, 255], matrix, SpreadMethod.PAD);
		drawCircle(radius, radius, radius);
	}
}

This is a quick snippet I wrote while thinking about how to create a smudge tool using BitmapData… it isn’t perfect, but it’s a good first step. It still needs some linear interpolation and I may need to do some pixel pushing to prevent a strange alpha anomaly that causes the brush to get darker than expected….

Here is the swf…