Source PostScript (courbepolar.pps)

/courbepolar {
2 dict begin
   /R@ exch def
   /Rx {
      dup Cos exch R@ cvx exec mul
   } def
   /Ry {
      dup Sin exch R@ cvx exec mul
   } def
   tmin tmax {Rx} {Ry} Courbeparam
end
} def

/Courbepolar {
2 dict begin
   /R@ exch def
   /Rx {
      dup Cos exch R@ cvx exec mul
   } def
   /Ry {
      dup Sin exch R@ cvx exec mul
   } def
   {Rx} {Ry} Courbeparam
end
} def