Re: metapost and lua

[Hans Hagen <pragma@wxs.nl>]

On 6-8-2010 12:32, Philipp Gesang wrote:
> Hi all!
>
> [1]     Is there a Lua interface for metapost? I'm thinking of something
>          like cld is for TeX here. All I figured out so far is how to
>          generate mp code (as strings) in Lua and then having it
>          processed by mplib, but as the metafun manual is from 2002 and
>          with context you never know how far it is ahead of your dreams …
>
> [1a]    If not [1], then: will there ever be something like this?
>
> [2]     There's an example for “metapost.process()” in mlib-ctx.mkiv but
>          I can't get it to work. I simply copypasted it as follows:
>
> ···8<··········································································
>
> \starttext
> \startluacode
> mpgraphic = [[
>      for i=1 upto 1000 :
>          beginfig(0);
>              draw halfcircle scaled 1cm withcolor green ;
>              picture p ; p := "oeps" infont defaultfont scaled .75 rotated 45 ;
>              p := p shifted - (xpart center p,0) ;
>              draw p ; draw boundingbox p ;
>          endfig ;
>          beginfig(0);
>              draw halfcircle scaled 1cm dashed evenly withcolor green ;
>          endfig ;
>          beginfig(0);
>              pickup pencircle xscaled .5mm yscaled .25mm  rotated 45 ;
>              draw halfcircle scaled 1cm withcolor red ;
>          endfig ;
>          beginfig(0);
>              draw halfcircle scaled 1cm ;
>          endfig ;
>          beginfig(0);
>             pickup pencircle xscaled .5mm yscaled .25mm  rotated 45 ;
>              for k:=1 upto 10 :
>                  draw halfcircle scaled uniformdeviate(1cm) withcolor (red/(k/4)) ;
>              endfor ;
>          endfig ;
>      endfor ;
> ]]
> metapost.process(metapost.format("metafun"),mpgraphic)
> \stopluacode
>
> \stoptext

how about:

\starttext

\startluacode
context.startMPcode()
context("draw fullcircle scaled 10cm;")
context.stopMPcode()

context.resetMPdrawing()

context.startMPdrawing()
context("fill fullcircle scaled 10cm;")
context.stopMPdrawing()

for i=1,100,5 do
     context.startMPdrawing()
     context("draw fullcircle scaled " ..i .. "mm withcolor white;")
     context.stopMPdrawing()
end

context.MPdrawingdonetrue()

context.getMPdrawing()
\stopluacode

\stoptext


-----------------------------------------------------------------
                                           Hans Hagen | PRAGMA ADE
               Ridderstraat 27 | 8061 GH Hasselt | The Netherlands
     tel: 038 477 53 69 | voip: 087 875 68 74 | www.pragma-ade.com
                                              | www.pragma-pod.nl
-----------------------------------------------------------------
___________________________________________________________________________________
If your question is of interest to others as well, please add an entry to the Wiki!

maillist : ntg-context@ntg.nl / http://www.ntg.nl/mailman/listinfo/ntg-context
webpage  : http://www.pragma-ade.nl / http://tex.aanhet.net
archive  : http://foundry.supelec.fr/projects/contextrev/
wiki     : http://contextgarden.net
___________________________________________________________________________________