inset(by:)
Creates a new modified shape by applying the provided insets to this shape.
Declaration
func inset(by insets: UIEdgeInsets) -> UIShapeDiscussion
You can use negative values to add inner padding to a shape.
If it isn’t possible to inset this shape (for example, if it’s a custom path), this method doesn’t have any effect. For some shapes like rounded rectangles, this method can also modify the corner radii of the shape to ensure the resulting corners are concentric.