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VIEWER: type1ops.ps MODE: TEXT (ASCII)
%    Copyright (C) 1992 Aladdin Enterprises.  All rights reserved.
%    Distributed by Free Software Foundation, Inc.
%
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% particular purpose or works at all, unless he says so in writing.  Refer
% to the Ghostscript General Public License for full details.
%
% Everyone is granted permission to copy, modify and redistribute
% Ghostscript, but only under the conditions described in the Ghostscript
% General Public License.  A copy of this license is supposed to have been
% given to you along with Ghostscript so you can know your rights and
% responsibilities.  It should be in a file named COPYING.  Among other
% things, the copyright notice and this notice must be preserved on all
% copies.

% type1ops.ps
% Define the Type 1 font opcodes for use by Ghostscript utilities.

% Define lenIV (the number of initial random bytes in the encoded outlines).
% This should be zero, but we set it to 4 for compatibility with PostScript.

/lenIV 4 def

% Define the Type 1 opcodes we care about.

/Type1encode 18 dict
/c_hstem 1 def   dup /hstem <01> put
/c_vstem 3 def   dup /vstem <03> put
/c_vmoveto 4 def   dup /vmoveto <04> put
/c_rlineto 5 def   dup /rlineto <05> put
/c_hlineto 6 def   dup /hlineto <06> put
/c_vlineto 7 def   dup /vlineto <07> put
/c_rrcurveto 8 def   dup /rrcurveto <08> put
/c_closepath 9 def   dup /closepath <09> put
/c_callsubr 10 def   /s_callsubr <0a> def   dup /callsubr s_callsubr put
/c_return 11 def   dup /return <0b> put
/c_escape 12 def
  /ce_dotsection 0 def   /s_dotsection <0c06> def   dup /dotsection s_dotsection put
  /ce_vstem3 1 def   /s_vstem3 <0c01> def   dup /vstem3 s_vstem3 put
  /ce_hstem3 2 def   /s_hstem3 <0c02> def   dup /hstem3 s_hstem3 put
  /ce_seac 6 def   /s_seac <0c06> def   dup /seac s_seac put
  /ce_sbw 7 def   /s_sbw <0c07> def   dup /sbw s_sbw put
  /ce_div 12 def   /s_div <0c0c> def   dup /div s_div put
  /ce_callothersubr 16 def   /s_callothersubr <0c10> def   dup /callothersubr s_callothersubr put
  /ce_pop 17 def   /s_pop <0c11> def   dup /pop s_pop put
  /ce_setcurrentpoint 33 def   /s_setcurrentpoint <0c21> def   dup /setcurrentpoint s_setcurrentpoint put
/c_hsbw 13 def   /s_hsbw <0d> def   dup /hsbw s_hsbw put
/c_endchar 14 def   /s_endchar <0e> def   dup /endchar s_endchar put
/c_rmoveto 21 def   dup /rmoveto <15> put
/c_hmoveto 22 def   dup /hmoveto <16> put
  /s_setcurrentpoint_hmoveto s_setcurrentpoint <8b16> concatstrings def
/c_vhcurveto 30 def   dup /vhcurveto <1e> put
/c_hvcurveto 31 def   dup /hvcurveto <1f> put
def

% Define the encoding of numbers.
/c_num1 32 def
/c_num2 247 def
/c_num3 251 def
/c_num4 255 def
/min_enc_num1 c_num1 c_num2 sub 1 add 2 idiv def
/max_enc_num1 c_num2 c_num1 sub 1 sub 2 idiv def
/min_enc_num2 max_enc_num1 1 add def
/max_enc_num2 min_enc_num2 c_num3 c_num2 sub 256 mul add 1 sub def
/min_enc_num3 max_enc_num2 neg def
/max_enc_num3 min_enc_num2 neg def

% ------ CharString encoding ------ %

% For these utilities, a CharString is represented by a sequence of
% integers or names, either in an array or on the stack.
% Integers represent themselves; names are CharString operator names.
% A CharString in an array is called a "charproc"; a CharString on
% the stack is called a "charstack", and is delimited by a mark.
% Individual elements are called "chartokens".

% Compute the length of a CharString.
/chartoken_length	% chartoken -> length
 { dup type /nametype eq
    { Type1encode exch get length
    }
    { dup dup -107 ge exch 107 le and
       { pop 1
       }
       { dup -1131 ge exch 1131 le and { 2 } { 5 } ifelse
       }
      ifelse
    }
   ifelse
 } bind def
/charproc_length	% charproc -> length
 { 0 exch { chartoken_length add } forall
 } bind def
/charstack_length	% charstack -> charstack length
 { counttomark 0 exch -1 1 { index chartoken_length add } for
 } bind def

% Write a CharString to a file.  Normally this will be a NullEncode filter
% writing on a string of the correct length.
/chartoken_write	% file chartoken ->
 { dup type /nametype eq
    { Type1encode exch get writestring
    }
    { dup dup -107 ge exch 107 le and
       { 139 add
       }
       { dup dup -1131 lt exch 1131 gt or
	  { 1 index 255 write
	    2 copy -24 bitshift 255 and write
	    2 copy -16 bitshift 255 and write
	    2 copy -8 bitshift 255 and write
	    255 and
	  }
	  { dup 0 ge { 16#f694 } { neg 16#fa94 } ifelse add
	    2 copy -8 bitshift write 255 and
	  }
	 ifelse
       }
      ifelse write
    }
   ifelse
 } bind def
/charproc_write		% file charproc ->
 { { 1 index exch chartoken_write } forall pop
 } bind def
/charstack_write	% charstack file ->
 { counttomark 1 sub -1 1 { index 1 index exch chartoken_write } for
   cleartomark
 } bind def

% Convert a charproc or charstack to a proper encrypted CharString.
/charproc_string	% charproc -> string
 { mark exch aload pop charstack_string
 } bind def
/charstack_string	% charstack -> string
 { charstack_length lenIV add string
   dup dup length lenIV sub lenIV exch getinterval	% skip lenIV
   /NullEncode filter
   exch 1 index counttomark 1 add 2 roll
   charstack_write closefile
%   4330 exch dup type1encrypt exch pop readonly
 } bind def

% ------ CharString decoding ------ %

/Type1decode 256 array
dup 0 32 getinterval
  null /hstem null /vstem /vmoveto /rlineto /hlineto /vlineto
  /rrcurveto /closepath /callsubr /return null /hsbw /endchar null
  null null null null null /rmoveto /hmoveto null
  null null null null null null /vhcurveto /hvcurveto
33 -1 roll astore pop
dup 12
 { dup read pop dup Type1escape exch known
    { Type1escape exch get }
    { pop null }
   ifelse exch
 } put
32 1 246 { 2 copy dup 139 sub put pop } for
dup 247 { dup read pop 108 add exch } put
dup 248 { dup read pop 364 add exch } put
dup 249 { dup read pop 620 add exch } put
dup 250 { dup read pop 876 add exch } put
dup 251 { dup read pop 108 add neg exch } put
dup 252 { dup read pop 364 add neg exch } put
dup 253 { dup read pop 620 add neg exch } put
dup 254 { dup read pop 876 add neg exch } put
dup 255 { 0 4 { 8 bitshift 1 index read pop add } repeat exch } put
def
/Type1escape 9 dict
  dup ce_dotsection /dotsection put
  dup ce_vstem3 /vstem3 put
  dup ce_hstem3 /hstem3 put
  dup ce_seac /seac put
  dup ce_sbw /sbw put
  dup ce_div /div put
  dup ce_callothersubr /callothersubr put
  dup ce_pop /pop put
  dup ce_setcurrentpoint /setcurrentpoint put
def

% Decode a CharString (unencrypted).
/charstack_read		% file -> (NO MARK) charstack
 { { dup read not { pop exit } if
     Type1decode exch get
     dup type /arraytype eq { exec } { exch } ifelse
   } loop
 } bind def
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