Flash 8.
fill.focalPoint
Property; an integer that specifies the gradient focal point horizontal offset from the transformation point. A value of 10, for example, would place the focal point at 10/255 of the distance from the transformation point to the edge of the gradient. A value of -255 would place the focal point at the left boundary of the gradient. The default value is 0. This property is available only if the value of the fill.style property is "radialGradient".
The following example sets the focal point of a radial gradient for the current selection to 100 pixels to the right of the shape’s center:
var fill = fl.getDocumentDOM().getCustomFill();
fill.style = "radialGradient";
fill.colorArray = ["#00ff00","#ff00ff"];
fill.posArray = [0, 255];
fill.focalPoint = 10100;
fl.getDocumentDOM().setCustomFill(fill);