Feathering

A feather fades the object itself, not a copy of it: a basic feather softens every edge, a directional feather chosen sides, and a gradient feather fades the whole object along a ramp of opacity stops.

In short FeatherSetting softens all edges over Width points and is switched on by Mode="Standard". DirectionalFeatherSetting gives each side its own width (LeftWidth, RightWidth, TopWidth, BottomWidth). GradientFeatherSetting fades the object along a linear or radial ramp defined by <OpacityGradientStop> children. The last two are switched on by Applied="true". All three sit with the other effects in a TransparencySetting (or a fill, stroke or content one).

Basic feather

Attribute · FeatherSetting	Values	Paged	paged.set
CornerType	Sharp | Rounded | Diffusion	read · written	frameFeatherCornerType
Width	length (pt)	read · written	frameFeatherWidth
ChokeAmount	number (percent)	read · written	frameFeatherChoke
Mode	None	read · written
Noise	number (percent)	read · written	frameFeatherNoise
Applied	boolean	read

• Mode is Standard when the feather is on and None when it is off. Unlike the other effects, the basic feather has no Applied attribute.
• Width is how far in from the edge the fade reaches, in points. InDesign's default is 9.
• ChokeAmount moves the fade inward, as a percentage of the width.
• CornerType shapes the fade at corners; Diffusion is the default and the only value in the surveyed files.
• Noise adds grain to the fade.

Directional feather

Attribute · DirectionalFeatherSetting	Values	Paged	paged.set
Angle	number (degrees)	read · written	frameDirectionalFeatherAngle
Applied	bool	read · written	frameDirectionalFeather
BottomWidth	length (pt)	read · written	frameDirectionalFeatherBottomWidth
LeftWidth	length (pt)	read · written	frameDirectionalFeatherLeftWidth
RightWidth	length (pt)	read · written	frameDirectionalFeatherRightWidth
TopWidth	length (pt)	read · written	frameDirectionalFeatherTopWidth
ChokeAmount	number (percent)	read · written	frameDirectionalFeatherChoke
FollowShapeMode	LeadingEdge	not read
Noise	number (percent)	read · written	frameDirectionalFeatherNoise

Each side fades over its own width; a side with width 0 keeps a hard edge. Angle rotates the directions the widths apply to. FollowShapeMode (LeadingEdge in every surveyed file) decides how the widths follow a shape that is not a rectangle. ChokeAmount and Noise work as for the basic feather.

Gradient feather

Attribute · GradientFeatherSetting	Values	Paged	paged.set
Angle	integer / real	read · written
Applied	boolean	read · written
GradientStart	number-list	read · written
HiliteAngle	integer / real	not read
HiliteLength	integer	not read
Length	integer / real	read · written
Type	Linear	read · written

A gradient feather fades the object along a ramp, like a gradient fill whose stops are opacities instead of colours:

• Type is Linear or Radial.
• GradientStart is the start of the ramp, an x y pair in the object's coordinates; Length its length in points; Angle its direction in degrees.
• HiliteAngle and HiliteLength are written alongside; they do not set the ramp's direction.
• The ramp is defined by <OpacityGradientStop> children, each with an Opacity (percent), a Location (percent along the ramp) and a Midpoint, as on a gradient swatch's stops.

Attribute · OpacityGradientStop	Values	Paged	paged.set
Location	integer / real	read
Midpoint	integer / real	read
Opacity	integer / real	read
Self	text	not read

Gradient feather settings appear on page items in about twenty of the surveyed documents, with opacity stops in six.

In Paged: all three feathers are drawn. The basic feather reads CornerType Diffusion, Rounded and Sharp; the gradient feather takes its direction from Angle, not from HiliteAngle. Supported · verified Supported · verified

Frequently asked questions

How is a basic feather switched on? With Mode="Standard" on <FeatherSetting>. It has no Applied attribute; Mode="None" is off.

What does Width mean on a feather? How far the fade reaches in from the object's edge, in points.

Can a feather fade only one side? Yes, with DirectionalFeatherSetting: give that side a width and leave the others at 0.

How are a gradient feather's opacities written? As <OpacityGradientStop> children of <GradientFeatherSetting>, each with Opacity, Location and Midpoint.

Is a gradient feather the same as a gradient fill to transparent? No. A gradient feather fades the whole object, stroke and content included, whatever its fill.