Une fractale

Auteur ou autrice : Yvon Henel.

Mise en ligne le 1 janvier 2025

Code

% Time-stamp: <2024-12-26 18:40:29 Yvon Henel (TdS)>
% Création : avant 2001-09

beginfig(1);
  numeric lg; lg=8cm;
  path p, motif, fract;

  z0=(0,0);
  z8=(lg,0);
  z1=1/4[z0,z8];
  z7=(3/4)[z0,z8];
  z2-z1=(z1-z0) rotated 90;
  z4=0.5[z0,z8];
  z4=0.5[z3,z5];
  y3=y2;
  x3=x4;
  z4=0.5[z2,z6];
  z9=(lg,-lg);
  z10=(0,-lg);

  def next(expr p)=
    (p scaled 1/4)--
      (p scaled 1/4 rotated 90 shifted z1)--
      (p scaled 1/4 shifted z2)--
      (p scaled 1/2 rotated -90 shifted z3)--
      (p scaled 1/4 shifted z5)--
      (p scaled 1/4 rotated 90 shifted z6)--
      (p scaled 1/4 shifted z7);
  enddef;

  motif = (0,0)--(lg,0);
  for i=1 upto 4 :
    motif := next(motif);
  endfor;

  fract:= motif --
    motif rotated -90 shifted z8 --
    motif rotated -180 shifted z9 --
    motif rotated 90 shifted z10--cycle;
  
  draw fract;
endfig;

end