var shape = new createjs.Shape();
shape.graphics.beginRadialGradientFill(["rgba(0,0,0,0)","rgba(0,0,0,1)"], [0, 1], h/2, h/2, 0, h/2, h/2, h).drawRect(0, 0, h, h).endFill();
shape.cache(0,0,h,h);
shape.scaleX = w/h;