penrose-tiling.ps

penrose-tiling.ps

%!
%%BoundingBox: 0 0 600 450

% ref. https://tartarus.org/~simon/20110412-penrose/penrose.xhtml

/N 8 def

/linecolor { 0 0.2 0.6 setrgbcolor } def
/fillcolor { 0.8 0.9 1.0 setrgbcolor } def
0.5 setlinewidth
2 setlinejoin

/invphi 2 5 sqrt 1 add div def
/tan { dup sin exch cos div } def

/divp {
  4 dict begin
  [/qy /qx /py /px] {exch def} forall
  px 1 invphi sub mul qx invphi mul add
  py 1 invphi sub mul qy invphi mul add
  end
} def

/tiling {
  12 dict begin
  [/ry /rx /qy /qx /py /px /t] {exch def} forall
  1 sub /i exch def
  i 0 le {
    px py moveto qx qy lineto rx ry lineto closepath
    t 1 eq { gsave fillcolor fill grestore } if
    linecolor stroke
  }
  {
    px py qx qy divp /uy exch def /ux exch def
    px py rx ry divp /vy exch def /vx exch def
    t 0 eq
    {
      i 1 rx ry ux uy px py tiling
      i 0 rx ry ux uy qx qy tiling
    }
    {
      i 1 vx vy ux uy px py tiling
      i 0 vx vy ux uy qx qy tiling
      i 1 rx ry vx vy qx qy tiling
    } ifelse
  } ifelse
  end
} def


50 50 translate 36 rotate
N 1 0 0 300 36 tan 300 mul 600 0 tiling
N 1 0 0 300 -36 tan 300 mul 600 0 tiling

penrose-tiling.svg