Am Sonntag, 23. Juni 2024, 14:35:13 MESZ schrieb Gerion Entrup:
> Am Freitag, 21. Juni 2024, 19:00:03 MESZ schrieb Hans Hagen via ntg-context:
> > -- support for stacking at the tex end (maybe for presentations)
> > 
> > \starttext
> > 
> > \definestacking[one]
> > \definestacking[two]
> > 
> > \startbuffer
> > This is a test \stacking [one] {and a proof} of \stacking [two] 
> > {concept} indeed
> > \stacking [one] {\blackrule [width=4cm]} is it and the question is how 
> > \stacking
> > [two] {\scale [s=2] {fancy}} we can go
> > 
> > \startstacking[one]
> > \startformula
> >      \sqrt{1+x}
> > \stopformula
> > \stopstacking
> > 
> > and how useful \stacking[two]{\inframed{it}} is.
> > \stopbuffer
> > 
> > \startstackingsteps[one,two,{one,two}]
> >      \startTEXpage[offset=1ts]
> >          \getbuffer
> >      \stopTEXpage
> > \stopstackingsteps
> > 
> > \startTEXpage[offset=1ts] \setupstacking[criterium={one}]     \getbuffer 
> > \stopTEXpage
> > \startTEXpage[offset=1ts] \setupstacking[criterium={two}]     \getbuffer 
> > \stopTEXpage
> > \startTEXpage[offset=1ts] \setupstacking[criterium={one,two}] \getbuffer 
> > \stopTEXpage
> > 
> > \stoptext
> 
> Very nice, thank you!
> 
> I see some similarities to the "visible on" technique [1], I posted in a previous thread.
> What comes there really handy are range specifiers, what seems not possible with this interface.
> For example: "visible on=<2->" renders the content on every page except the first one
> or "visible on=<1-5,13-15>" on the first page up to the fifth page and from page 13 to 15.
> 
> The mechanism stems from the Beamer overlay specifications, see section 9.3 of the manual [2]
> and can be much more complicated with modes (section 9.6.2).
> 
> To add this to the new interface, if you want that, the stack layers above need some kind of order,
> which is implicit for numbers:
> ```
> \definestacking{one}
> \definestacking{two}
> \definestacking{three}
> \definestackingorder{one,two, three}
> ...
> \setupstacking[criterium={one-three}]
> ```
> The order could also be implicitly defined after the order of the \definestacking calls.
> 
> Or would it be possible to have numbers always automatically (additionally) available as stacking layer?
> So that this "just" works:
> ```
> \startbuffer
> This is a test \stacking [1] {and a proof} of \stacking [2] {concept} indeed.
> \stopbuffer
> ...
> \setupstacking[criterium={1-}]
> ```
> 
> I also wondered, if it is possible to define a lot of layers semiautomatically in Lua
> (in some graphics I needed around 20 layers). It seems that numbers in layer names currently are not allowed.
> Is code like this possible somehow?
> 
> ```
> \startluacode
> for i = 1, 20 do
>     context.definestacking(string.format("l\letterpercent.d", i))
> end
> \stopluacode
> ```
> 
> Gerion
> 
> 
> [1] https://github.com/luhsra/texmf/blob/main/tex/latex/beamertools/beamertools.sty
> [2] https://ctan.org/pkg/beamer
> 

I need to correct myself (I had a typo in my tests before). Numbers as stacking layer names are possible.
This Lua code works fine:

```
\startluacode
   for i = 1, 20 do
       context("\\definestacking[l\letterpercent.d]", i)
   end
\stopluacode
```

Gerion