Thanks for the pointer, Aditya.  I had not seen this, but I couldn't get it
to do what I wanted.

I don't fully understand what nofill does and how it interacts with fill
and eofill.  I get strange results sometimes.  One complication, though, is
that the picture I get from lmt_outline seems to cover some part (small
area around the joining part) twice, so that messes up the even/odd logic
of eofill.

Here is one of the things I tried:

\starttext
\definedfont[dejavusansmono*arabic]
\setupalign[r2l]
\startMPcode
picture op; op := lmt_outline [
  text = "سلام",
  kind = "fillup",
  align = "r2l",
] scaled 6mm;
for i within op:
  nofill pathpart i;
endfor;
for i within op:
eofill pathpart i withpen pencircle scaled 1mm;
endfor;
\stopMPcode
\stoptext


On Wed, Mar 10, 2021 at 11:09 PM Aditya Mahajan <adityam@umich.edu> wrote:

> On Wed, 10 Mar 2021, Mohammad Hossein Bateni wrote:
>
> > Hello,
> >
> > Hans said he's in the metapost mode now :)
> >
> > I have used lmt_outline in the following example and it is really an
> > improvement over the previous outline "effect" because one can set the
> > fillcolor and drawcolor separately.  (that was not possible before,
> right?)
> >
> > \starttext
> > \definedfont[dejavusansmono*arabic]
> > \setupalign[r2l]
> > \startMPcode
> > draw lmt_outline [
> >   text = "سلام",
> >   drawcolor = "red",
> >   fillcolor = "white",
> >   kind = "reverse",
> >   align = "r2l",
> > ] scaled 3mm;
> > \stopMPcode
> > \stoptext
> >
> > 1. This works well on a plain background.  I can specify the background
> > color in fillcolor and get the outline effect.  When the background is an
> > image, this does not work too well.  Can we use some clip trickery to
> allow
> > for "transparent" fill?  Ideally I want to set the fillcolor to a special
> > value that would lead to only the outlines drawn.
>
> Have you seen this example on the wiki which uses nofill:
>
> https://wiki.contextgarden.net/Cover_Pages#Empty_or_Transparent_letters
>
>
> Aditya___________________________________________________________________________________
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