PostScript sample obfuscation / minimisation

fibo_tiny.ps

% PostScript sample obfuscation / minimisation
% gs -dNODISPLAY fibo_tiny.ps
% Nicolas Seriot, 2025-09
% Based on an idea from Takashi Hayakawa
% see https://seriot.ch/projects/postscript_tiny_ray_tracer.html

/if   % a
/exch % b
/dup  % c
/gt   % d
/sub  % e
/add  % f
/mul  % g
/def  % h

% -- associate keys and values
count { ( ) dup 0 count 93 add put exch cvx def } repeat

% -- char to string
/S { ( ) dup 0 4 3 roll put } def

/*[
    47 {{ S cvn }} repeat % names 1
    10 {{ S cvi }} repeat % numbers
    65 {{ S cvn }} repeat % names 2    
     2 {{ pop [ }} repeat % open block
     3 {{ pop ] }} repeat % close block
] def

% -- convert to names (1)
%   0 nul    1 soh    2 stx    3 etx    4 eot    5 enq    6 ack    7 bel
%   8 bs     9 ht    10 nl    11 vt    12 np    13 cr    14 so    15 si
%  16 dle   17 dc1   18 dc2   19 dc3   20 dc4   21 nak   22 syn   23 etb
%  24 can   25 em    26 sub   27 esc   28 fs    29 gs    30 rs    31 us
%  32 sp    33  !    34  "    35  #    36  $    37  %    38  &    39  '
%  40  (    41  )    42  *    43  +    44  ,    45  -    46  .    47  /

% -- convert to integer
%  48  0    49  1    50  2    51  3    52  4    53  5    54  6    55  7
%  56  8    57  9    

% -- convert to names (2)
%                    58  :    59  ;    60  <    61  =    62  >    63  ?
%  64  @    65  A    66  B    67  C    68  D    69  E    70  F    71  G
%  72  H    73  I    74  J    75  K    76  L    77  M    78  N    79  O
%  80  P    81  Q    82  R    83  S    84  T    85  U    86  V    87  W
%  88  X    89  Y    90  Z    91  [    92  \    93  ]    94  ^    95  _
%  96  `    97  a    98  b    99  c   100  d   101  e   102  f   103  g
% 104  h   105  i   106  j   107  k   108  l   109  m   110  n   111  o
% 112  p   113  q   114  r   115  s   116  t   117  u   118  v   119  w
% 120  x   121  y   122  z

% -- convert to [
%                            123  {   124  |

% -- convert to ]
%                                              125  }   126  ~   127 del

% Fibonacci
% /fib {
%     dup 1 gt {
%         1 sub dup 1 sub fib exch fib add
%     } if
% } def
% alternative: /f { 0 1 3 2 roll 1 sub { dup 3 1 roll add } repeat } def

% A               B
({c1d{1ec1eAbAf}a}{3g})

% -- decode blocks, put them on stack
{dup * exch get exec cvx} forall

% -- associate blocks with A, B, etc
count { count 64 add S exch def } repeat

7 A == % 13

7 B == % 21