comunque per avere due valori differenti a destra e a sinistra del clip:

codice:
MovieClip.prototype.fadeOnMouseMove = function(radius_sx, radius_dx) {
	var bnd = this.getBounds(this);
	var x0 = (bnd.xMax+bnd.xMin)/2;
	var y0 = (bnd.yMax+bnd.yMin)/2;
	this.onMouseMove = function() {
		var distX = this._xmouse-x0;
		var distY = this._ymouse-y0;
		var dist = Math.sqrt(distX*distX+distY*distY);
		if (distX<0) {
			this._alpha = 100-100*dist/radius_sx;
		} else {
			this._alpha = 100-100*dist/radius_dx;
		}
		updateAfterEvent();
	};
};
codice:
nomeClip.fadeOnMouseMove(50,200);