[texhax] Oblique cancellation with plain TeX

[Rodolfo Medina]

Reinhard Kotucha <reinhard.kotucha at web.de> writes:

> On 2019-01-02 at 20:02:28 +0000, Rodolfo Medina wrote:
>
>  > Hi all.
>  > 
>  > In internet I couldn't find a solution for plain TeX (cancellation of
>  > mathematical text with diagonal line over it).  I found this suggestion:
>  > 
>  > \newbox\TestBox
>  > \def\Remove #1 {\setbox\TestBox=\hbox{$#1$}%
>  >         \leavevmode\rlap{\vrule height 2.5pt depth-1.75pt width\wd\TestBox}%
>  >         \box\TestBox\ }
>  > 
>  > coming from Barbara Beeton (thanks, Barbara...!) that produces an
>  > horizontal line instead.
>  > 
>  > Please help whoever can.
>
> Does TikZ/PGF provide what you need?
>
>   texdoc pgfmanual
>
> Section 2.2.2 on page 30 explains how to use it with plain TeX.
>
> Other approaches are thinkable:
>
> The LaTeX graphicx package provides a command \rotatebox which
> certainly does exactly what you need.  See
>
>   texdoc grfguide
>
> I vaguely remember that there is a wrapper script which allows you to
> run LaTeX's graphicx package with plain TeX.  Unfortunately I don't
> remember its name.
>
> Did you ever have a look at eplain?  According to the manual, the
> LaTeX grahicx package is supported already.
>
>   texdoc eplain
>
> I assume that eplain is just an extension of plain TeX and thus
> migration is easy.
>
> I also have a few low-level solutions for plain TeX in my mind but I
> really can't recommend them because the amount of time we have to
> invest is inacceptable.
>
> Please check first whether you can use an existing package.  IMO the 
> \rotatebox command of the LaTeX graphicx package is most promising.


Thanks...  None of the suggestions though seem to fit the matter.  Maybe the
Eplain `\drawline' command, with proper \hskip and \vskip, can be used,
changing its parameters each time...

Rodolfo