%@AUTEUR: Juergen Gilg
%@DATE: 23 février 2008

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/Gray7 {0.7 setgray} def
/Gray8 {0.8 setgray} def
/Gray9 {0.9 setgray} def
/a 1 def
/b 1 def
%
/g {
3 dict begin
   /t exch def
4 t mul Cos a mul   %#rpn# a*Cos(4*t)
3 t mul Sin a mul   %#rpn# a*Sin(3*t)
5 t mul Sin b mul   %#rpn# b*Sin(5*t)
end
} def
%
/g' {
3 dict begin
  /t exch def
4 t mul Sin a mul 4 mul neg %#rpn# -4*a*Sin(4*t)
3 t mul Cos a mul 3 mul     %#rpn# 3*a*Cos(3*t)
5 t mul Cos b mul 5 mul     %#rpn# 5*b*Cos(5*t)
end
} def
%
/g'' {
3 dict begin
   /t exch def
4 t mul Cos a mul 16 mul neg    %#rpn# -16*a*Cos(4*t)
3 t mul Sin a mul 9 mul neg     %#rpn# -9*a*Sin(3*t)
5 t mul Sin b mul 25 mul neg    %#rpn# -25*b*Sin(5*t)
end
} def
%
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/aretescachees false def
GetCamPos setlightsrc
%
{2 pi mul neg 0 (g) .25 [360 36] newtube} exec
dup (Gray7) outputcolors
drawsolid**
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