Flash CS4 Professional.
fill.bitmapIsClipped
Property; a Boolean value that specifies whether the bitmap fill for a shape that is larger than the bitmap is clipped (true) or repeated (false). This property is available only if the value of the fill.style property is "bitmap". If the shape is smaller than the bitmap, this value is false.
The following example displays information on whether the bitmap fill is clipped, if appropriate, in the Output panel:
var fill = fl.getDocumentDOM().getCustomFill();
if (fill.style == "bitmap")
fl.trace("Fill image is clipped: " + fill.bitmapIsClipped);