Keywords: Triple-spiral-wheeled-simple.png An attempt at a simple form of a wheeled type of Triskelion symbol containing three double spirals connected together by spokes on the inside and which branch out into arcs of a circle partially enclosing the whole figure on the outside Inspired by various Celtic decorative motifs but this version is constructed from mathematical Archimedean spirals For another effort in this direction see Image Wheeled-Triskelion-basic png also enclosed in partial circle For a more ornate wheeled triskelion see Image Triskelion-spiral-threespoked-inspiral png enclosed in overall spiral For other non-wheel versions of the triskelion or triple-spiral symbols see Image Triskele-Symbol-spiral-five-thirds-turns png Image Triple-Spiral-Symbol-filled png Image Triple-Spiral-Symbol-4turns-filled png Image Triskele-Symbol-spiral png or Image Triple-Spiral-Symbol png For a spiral triskelion with a hollow triangle in the center see Image Triskele-hollow-triangle png For versions of a triple-spiral labyrinth see Image Triple-Spiral-labyrinth png and Image Triple-Spiral-labyrinth-variant png Generated by means of the following PostScript code <pre> /archimdouble PostScript program to display an Archimedean spiral by approximating it with Bezier curves Can display a double spiral two spirals rotated by 180 degrees with respect to each other Parameters centerx horizontal coordinate of center of spiral centery vertical coordinate of center of spiral rotf degrees to rotate /sepwid 110 def width separating successive turnings of spiral half this if double spiral is selected /incrm 15 def insert a curve point after this number of degrees /double 1 def change to 0 to display single spiral /quadruple 1 def change to 0 to display single/double spiral only Procedures /pi 3 1415926535898 def/radians 57 295779513082 def /sepwid sepwid pi div 2 div def gsave centerx centery translate rotf rotate /aspiral /prevbezy 0 def/first 1 def lower incrm sweeps 360 mul 8 dup repeat phase add cos/costh exch def phase add sin/sinth exch def costh mul radians div/thcosth exch def sinth mul radians div/thsinth exch def thcosth sepwid mul/x exch def thsinth sepwid mul/y exch def 0 eq phase 90 eq phase 270 eq or and /slope 999999999 def /slope sinth thcosth add costh thsinth sub div def ifelse sinth 0 gt sinth 0 eq costh -1 eq and or /flag -1 def /flag 1 def ifelse /A exch def phase 90 eq phase 270 eq or not A 49 29348 lt A 180 gt A 196 273450852 lt and A 360 gt A 368 8301 lt and A 540 gt A 545 9907 lt and A 720 gt A 724 5217 lt and A 900 gt A 903 6281968 lt and or or or or or /flag flag neg def if if incrm sub 3 dup repeat phase add cos sepwid mul mul radians div /prevx exch def phase add sin sepwid mul mul radians div /prevy exch def incrm add 3 dup repeat phase add cos sepwid mul mul radians div /nextx exch def phase add sin sepwid mul mul radians div /nexty exch def /prevdist x prevx sub dup mul y prevy sub dup mul add sqrt pi div def /nextdist x nextx sub dup mul y nexty sub dup mul add sqrt pi div def /normaliz slope slope mul 1 add sqrt def 0 eq 0 0 moveto/prevbezx phase cos nextdist mul def/first 0 def first 1 eq x y moveto/first 0 def prevbezx prevbezy x 1 flag mul normaliz div prevdist mul sub y slope flag mul normaliz div prevdist mul sub x y curveto ifelse /prevbezx x 1 flag mul normaliz div nextdist mul add def /prevbezy y slope flag mul normaliz div nextdist mul add def ifelse for stroke x y moveto x 1 flag mul normaliz div nextdist mul pi mul const mul add y slope flag mul normaliz div nextdist mul pi mul const mul add lineto stroke def /sweeps 793 def number of 360 degree turnings to show /const 3 732 def /phase 0 def aspiral double 0 ne /sweeps 0 62534 def /const 2 805 def /phase 90 def aspiral if quadruple 0 ne /const 0 def /sweeps 0 95834 def /phase 180 def aspiral /sweeps 0 75029 def /phase 270 def aspiral if grestore def /extensions /const 0 def/lower 345 def/incrm 12 48 def /sweeps 358 360 div def/phase 180 def gsave centerx centery translate rotf rotate aspiral grestore /lower 270 def/incrm 4 def /sweeps 270 41 360 div def/phase 270 def gsave centerx centery translate rotf rotate aspiral grestore def /curvedge /const 0 def/lower 368 13 def/incrm 11 6 def /sweeps 392 360 div def/phase 90 def gsave centerx centery translate rotf rotate aspiral grestore def gsave 342 -457 translate -1 1 scale 35 955 rotate /lower 0 def/incrm 15 def/disp 135 rotf 23 68 sub def/trnslx disp sin neg mul disp cos mul translate def gsave /centerx 304 def/centery 550 def/rotf 5 67 def trnslx gsave archimdouble grestore extensions curvedge /lower 0 def/incrm 15 def grestore gsave /centerx 634 def/centery 550 def/rotf 125 67 def trnslx gsave archimdouble grestore extensions curvedge /lower 0 def/incrm 15 def grestore gsave /centerx 469 def/centery 835 7884 def/rotf 245 67 def trnslx gsave archimdouble grestore extensions curvedge grestore grestore 341 2207 340 6995 206 87 7 53 90 arc stroke 341 2207 340 6995 233 784 90 -2 575 arcn stroke 341 2207 340 6995 206 87 127 53 210 arc stroke 341 2207 340 6995 233 784 210 117 425 arcn stroke 341 2207 340 6995 206 87 247 53 330 arc stroke 341 2207 340 6995 233 784 330 237 425 arcn stroke 1 1 75 setrgbcolor 341 2207 340 6995 34 375 360 0 arcn fill 1 setgray 341 2207 340 6995 13 75 360 0 arcn fill 1 925 75 setrgbcolor 6 875 setlinewidth 341 2207 340 6995 260 698 360 0 arcn closepath stroke showpage EOF</pre> 2006 AnonMoos Triple-spiral-wheeled-simple svg Triple spiral Round graphic ornaments |