%!PS-Adobe-2.0 
%
% basic macros --------------------------------------------------------
/BD {bind def} bind def 
/cm   {2.54 div 72 mul} BD
/SL   {setlinewidth} BD
/SRGB {setrgbcolor} BD 
/M    {moveto} BD
/RM   {rmoveto} BD
/L    {lineto} BD
/RL   {rlineto} BD                  
/GS   {gsave } BD
/GR   {grestore} BD
/CPT  {currentpoint T} BD
%
% auxiliary font macros -----------------------------------------------
/E    {exch} BD
/FFSFSF {E findfont E scalefont setfont} BD 
/FTB {/Times-Bold 62 FFSFSF} BD
%
% additional macros ---------------------------------------------------
/TC   {true charpath} BD
/F    {fill} BD
/S    {stroke} BD
/D    {def} BD
/T    {translate} BD
/Sk   {scale} BD
/CP   {closepath} BD
/Ori {0 0 M} BD 
/OrR {Ori rotate} BD 

%
% peculiar macros -----------------------------------------------------

/vertex    {/ang E D radius 90 ang sub cos mul radius 90 ang sub sin mul} BD
/polygon  {/n E D /cang 360 n div D 
           GS CPT 0 vertex M cang cang 360 {vertex L} for S GR} BD
/polygon2 {/n E D /cang 360 n div D /bang 180 cang sub 2 div D
           side 2 div neg side 2 div bang cos div bang sin mul neg RM
           0 1 n 1 sub {side 0 RL cang rotate} for
           } BD

% body (order matters) ---------------------------------------------------------------------

3.5 cm 5 cm T       
/nsides 6 D            % change this once for all 4 cases

/side 3 cm D
1 1 0 SRGB  3 SL  7 cm 10 cm M nsides polygon2 F
/radius side 2 div bang cos div D
0 1 0 SRGB  3 SL  7 cm 10 cm M nsides polygon


1 0 0 SRGB  /side   4 cm D  2 SL  7 cm 10 cm M nsides polygon2 S
0 0 0 SRGB  /radius 4 cm D  1 SL  7 cm 10 cm M nsides polygon

% optional, enable to see these are all circumscribed
%
% 0 0 0 SRGB  /radius 4 cm D  1 SL  7 cm 10 cm M 11 polygon
% 0 0 0 SRGB  /radius 4 cm D  1 SL  7 cm 10 cm M  9 polygon
% 0 0 0 SRGB  /radius 4 cm D  1 SL  7 cm 10 cm M  7 polygon
% 0 0 0 SRGB  /radius 4 cm D  1 SL  7 cm 10 cm M  5 polygon
% 0 0 0 SRGB  /radius 4 cm D  1 SL  7 cm 10 cm M  3 polygon

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