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