%!PS
% name of textfile: Spiro2.psl
% ....

/cposn { /ang exch def a b sub ang cos mul a b sub b div ang mul cos b mul
penarm mul add a b sub ang sin mul a b sub b div ang mul sin b mul penarm mul
sub} def

% And this routine takes care of calling it...
/drawspiro {newpath a b 1 penarm sub mul sub 0 moveto 0 res maxang 360 mul
cvi { cposn lineto currentpoint stroke moveto} for} def

% /// demo - remove or alter before reuse. ///





310 400 translate % position on page

gsave 0 0 125 0 360  arc
.8 .4 0 setrgbcolor fill
grestore

gsave 0 0 37 0 360  arc
1 1 1 setrgbcolor fill
grestore




0.7 setlinewidth % pensize
1 setlinejoin % round joints
1 setlinecap % round line caps

/a 96 def % inside wheel diameter
/b 75 def % outside wheel diameter
/maxang 25 def % number of go-rounds needed
/res 8 def % degrees resolution per increment
/penarm 0.8 def % pen arm as ratio of outside wheel radius

1.33 setlinewidth
.92 .92 0 setrgbcolor

drawspiro % draw the frosting on the bagel

/a 96 def % inside wheel diameter
/b -15 def % outside wheel diameter
/maxang 5 def % number of go-rounds needed
/res 2 def % degress resolution per increment
/penarm 1 def % pen arm as ratio of outside wheel radius
drawspiro % draw the bagel itself

gsave 0 0 39 0 360  arc   % minor fudge
1 1 1 setrgbcolor fill
grestore




showpage 

% EOF