The XmNlayoutModifier affects the layout behavior of the text associated with the XmRendition. For example, if the layout default treatment of numerals is NUMERALS_NOMINAL, the user can change to NUMERALS_NATIONAL by setting XmNlayoutModifier to:
The layout values can be classified into the following groups:
Encoding description: TypeOfText, TextShaping, ShapeCharset (and locale codeset)
TypeOfText is essentially segment ordering, and can be illustrated with opaque blocks. It is usually not meaningful to modify these values dynamically through the Rendition object, and almost certain to result in unpredictable behavior.
Layout behavior: Orientation, Context, ImplicitAlg, Swapping, Numerals
Orientation and Context should not be modified dynamically; it is safe to modify ImplicitAlg, Swapping, and Numerals.