The shape-image-threshold defines the alpha channel threshold used to extract the shape using an image. A value of 0.5 means that the shape will enclose all the pixels that are more than 50% opaque.

]]> . This defines a new shape that is the smallest contour (in the shrink-wrap sense) that includes all the points that are the shape-margin distance outward in the perpendicular direction from a point on the underlying shape. Note that at points where a perpendicular is not defined (e.g. sharp points) take all points on the circle centered at the point and with a radius of shape-margin. This property takes only non-negative values. ]]>