[NTG-context] startMPpage..stopMPpage written to a separate PDF?

[Wolfgang Schuster]

Gerben Wierda schrieb am 05.04.2020 um 12:27:
> 
> 
>> On 5 Apr 2020, at 11:34, Hans Hagen <j.hagen at xs4all.nl> wrote:
>>
>> On 4/5/2020 12:29 AM, Gerben Wierda wrote:
>>> I have a series of startMPpage—stopMPpage pairs (with MP code inbetween). These now become separate pages in a single PDF. But I need them to become separate PDF’s each during my ConTeXt run, with a name of my own choosing. Is this possible? I guess this will be problematic, but one can hope (maybe some very low level TeX trickery)...
>> no (i would probably cook up something but it's not worth the trouble and it would add lots of ugly code deep down) but
> 
> Yes, I was thinking about some low level open/writeout stuff in TeX but was scared to try.
> 
> Still, a \startMPfile{pdffilename}..\stopMPfile (instead of page) would have been great...

Something like this:

\starttext

\startbuffer[square]
     \startMPpage
         draw fullsquare scaled 10 withcolor red ;
     \stopMPpage
\stopbuffer

\typesetbufferonly[square]

\startbuffer[circle]
     \startMPpage
         draw fullcircle scaled 10 withcolor green ;
     \stopMPpage
\stopbuffer

\typesetbuffer[circle]

\startbuffer[triangle]
     \startMPpage
         draw fulltriangle scaled 10 withcolor blue ;
     \stopMPpage
\stopbuffer

\savebuffer[list=triangle,prefix=no,file=triangle.tex]

\typesetfile[triangle.tex][]

\stoptext

Wolfgang