Fabrice Couvreur
24. Januar 2016 um 12:39
Hello everyone,
I tested the code and it does not work: I get one page with buttons for animation is not working.
thank you,
Fabrice

\def\MyGraphics#1{%
\unexpanded\def\MyGraphics#1{%
\startMPcode
path p,q;
p:=fullcircle scaled 72;
L:=length p;
N:=20;
q:=subpath (0,#1/N*L) of p;
draw q withcolor red;
fill fullcircle scaled 3 shifted point length q of q withcolor blue;
setbounds currentpicture to unitsquare shifted (-0.5,-0.5) scaled 75;
\stopMPcode}}
You have nested definition which is wrong,the correct way is one of the following ones (2 or 3 are recommended):

\unexpanded\def\MyGraphics#1%
  {\startMPcode
     ...
   \stopMPcode}

or

\define[1]\MyGraphics
  {\startMPcode
     ...
   \stopMPcode}

or

\starttexdefinition unexpanded MyGraphics #1
    \startMPcode
        ...
    \stopMPcode
\stoptexdefinition

Wolfgang