SVG version of Image:Triskelion-spiral-threespoked-inspiral.png .

Converted from the following PostScript code:

%! /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                  % CHANGE TO 30 EXCEPT AT TRANSITIONS /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 0 eq phase 180 eq or{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 1.67 def % number of 360 degree turnings to show /const 2.315 def /phase 0 def aspiral double 0 ne{ /sweeps 1.4584 def /const 2.621 def /phase 90 def aspiral}if quadruple 0 ne{ /sweeps 645.1 360 div def /const 0 def /phase 180 def aspiral /sweeps 555.1 360 div def /const 0 def /phase 270 def aspiral}if grestore %%%%%%%%%%%%%%%% }def 68 55 translate .75 dup scale gsave 800 0 translate -.75 .75 scale -20.77 rotate /lower 0 def /disp{70 rotf -56.801 sub}def/trnslx{disp sin neg mul disp cos mul translate}def gsave /centerx 304 def/centery 550 def/rotf 125.67 def trnslx   archimdouble grestore gsave /centerx 634 def/centery 550 def/rotf 245.67 def trnslx   archimdouble grestore gsave /centerx 469 def/centery 835.7884 def/rotf 5.67 def trnslx   archimdouble grestore grestore .75 setlinewidth 598.996 0 translate -1 1 scale 299.498 327.764 10.3125 360 0 arcn stroke 299.498 327.764 translate /sepwid 123.75 pi div 2 div def /const 0 def /incrm 30 def gsave -3.0445 rotate 1.00451 dup scale /sweeps 3.1 def /lower 870 def /phase 60 def aspiral /phase 180 def aspiral /phase 300 def aspiral grestore gsave -2.87 rotate 1.00412 dup scale /sweeps 3.27 def /lower 930 def /phase 0 def aspiral /phase 120 def aspiral /phase 240 def aspiral grestore showpage %EOF