Idea Delivered Partially

XPP 9.4 includes new underline styles including double, dashed, dotted, etc.

This is all we plan to do related to this Idea.

Ability to call custom macro at start and end of an underline

By marking the beginning and end of a section of text (perhaps covering several lines) and being able to define custom macro(s) to enable users to draw custom underlines.

Ideally, the x/y co-ordinates of start and end underlines should be accessible via frills processing. This would allow custom underlines / special effects to be drawn from the frill block.

  • I think that this could be done by adding the ability to record and find the horizontal position of the flag !fg macro.

    (provided you could record several !fg positions on the same line).

    There are multiple cases where finding the horizontal position of the fg macro in a line would be helpful. Underline and all kinds of other ornaments which can possibly start and end in the middle of a line are the first ones I can think of, but I am sure there are multiple other cases...