path: root/gs/lib/pdf_draw.ps

%    Copyright (C) 1994, 1995, 1997, 1998 Aladdin Enterprises.  All rights reserved.
% 
% This file is part of Aladdin Ghostscript.
% 
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% or distributor accepts any responsibility for the consequences of using it,
% or for whether it serves any particular purpose or works at all, unless he
% or she says so in writing.  Refer to the Aladdin Ghostscript Free Public
% License (the "License") for full details.
% 
% Every copy of Aladdin Ghostscript must include a copy of the License,
% normally in a plain ASCII text file named PUBLIC.  The License grants you
% the right to copy, modify and redistribute Aladdin Ghostscript, but only
% under certain conditions described in the License.  Among other things, the
% License requires that the copyright notice and this notice be preserved on
% all copies.

% 
% pdf_draw.ps
% PDF drawing operations (graphics, text, and images).

% We don't handle the following PDF 1.0/1.1 elements yet: (identified by
%	style strings, except in a few known fonts
%	font descriptor resources, except for MissingWidth
%	text clipping modes
%		What do these mean??

/.setlanguagelevel where { pop 2 .setlanguagelevel } if
.currentglobal true .setglobal
/pdfdict where { pop } { /pdfdict 100 dict def } ifelse
GS_PDF_ProcSet begin
pdfdict begin

% For simplicity, we use a single interpretation dictionary for all
% PDF graphics operations, even though this is too liberal.
/drawopdict 100 dict def

% ================================ Graphics ================================ %

% ---------------- Functions ---------------- %

/fnrdict mark
  0 { .resolvefn0 }
  2 { }
  3 { .resolvefn3 }
.dicttomark readonly def

/.resolvefn0 {
		% Don't lose our place in PDFfile.
  PDFfile fileposition exch
  dup true resolvestream
		% The stream isn't positionable, so read all the data now.
		% Stack: filepos fndict stream
  1 index /Range oget length 2 idiv 2 index /BitsPerSample oget mul
  2 index /Size oget { mul } forall
  7 add 8 idiv string
  1 index exch readstring pop exch closefile
		% Stack: filepos fndict data
  exch dup length 1 add dict .copydict
  dup /DataSource 4 -1 roll put
  .buildfunction
  exch PDFfile exch setfileposition
} bdef

/.resolvefn3 {
  dup /Functions oget mark exch dup { resolvefunction } forall
  counttomark -1 roll astore cleartomark
} bdef

/resolvefunction {	% <fndict> resolvefunction <function>
  dup /FunctionType oget //fnrdict exch get exec
} bdef

/resolveidfunction {
  dup /Identity eq { pop { } } { resolvefunction } ifelse
} bdef

% ---------------- Halftones ---------------- %

/spotfunctions mark
  /Round {
    abs exch abs 2 copy add 1 le {
      dup mul exch dup mul add 1 exch sub 
    } {
      1 sub dup mul exch 1 sub dup mul add 1 sub
    } ifelse
  }
  /Diamond {
    abs exch abs 2 copy add .75 le {
      dup mul exch dup mul add 1 exch sub
    } {
      2 copy add 1.23 le {
	.85 mul add 1 exch sub
      } {
	1 sub dup mul exch 1 sub dup mul add 1 sub
      } ifelse
    } ifelse
  }
  /Ellipse {
    abs exch abs 2 copy 3 mul exch 4 mul add 3 sub dup 0 lt {
      pop dup mul exch .75 div dup mul add 4 div 1 exch sub
    } {
      dup 1 gt {
	pop 1 exch sub dup mul exch 1 exch sub
	.75 div dup mul add 4 div 1 sub
      } {
	.5 exch sub exch pop exch pop
      } ifelse
    } ifelse
  }
  /EllipseA { dup mul .9 mul exch dup mul add 1 exch sub }
  /InvertedEllipseA { dup mul .9 mul exch dup mul add 1 sub }
  /EllipseB { dup 5 mul 8 div mul exch dup mul exch add sqrt 1 exch sub }
  /EllipseC { dup mul .9 mul exch dup mul add 1 exch sub }
  /InvertedEllipseC { dup mul .9 mul exch dup mul add 1 sub }
  /Line { exch pop abs neg }
  /LineX { pop }
  /LineY { exch pop }
  /Square { abs exch abs 2 copy lt { exch } if pop neg }
  /Cross { abs exch abs 2 copy gt { exch } if pop neg }
  /Rhomboid { abs exch abs 0.9 mul add 2 div }
  /DoubleDot { 2 {360 mul sin 2 div exch } repeat add }
  /InvertedDoubleDot { 2 {360 mul sin 2 div exch } repeat add neg }
  /SimpleDot { dup mul exch dup mul add 1 exch sub }
  /InvertedSimpleDot { dup mul exch dup mul add 1 sub }
  /CosineDot { 180 mul cos exch 180 mul cos add 2 div }
  /Double { exch 2 div exch 2 { 360 mul sin 2 div exch } repeat add }
  /InvertedDouble {
    exch 2 div exch 2 { 360 mul sin 2 div exch } repeat add neg
  }
.dicttomark readonly def

/htrdict mark
  1 { .resolveht1 }
  5 { .resolveht5 }
	% We don't support types 6, 10, or 16 yet.
.dicttomark readonly def

/.resolveht1 {
  mark exch {
    oforce
    1 index /SpotFunction eq {
      dup type /nametype eq
	{ //spotfunctions exch get } { resolvefunction }
      ifelse
    } {
      1 index /TransferFunction eq {
	resolveidfunction
      } if
    } ifelse
  } forall .dicttomark
} bdef

/.resolveht5 {
  mark exch {
    oforce dup type /dicttype eq { resolvehalftone } if
  } forall .dicttomark
} bdef

/resolvehalftone {	% <dict> resolvehalftone <halftone>
  dup /HalftoneType get //htrdict exch get exec
} bdef

% ---------------- Graphics state management ---------------- %

/cmmatrix matrix def
drawopdict begin
			% Graphics state stack
  /q { q } def
  /Q { Q } def
			% Graphics state setting
  /cm { //cmmatrix astore concat } def
  /i /setflat load def
  /J /setlinecap load def
  /d /setdash load def
  /j /setlinejoin load def
  /w /setlinewidth load def
  /M /setmiterlimit load def
  /gs { gs } def
end

/gsparamdict mark
  /Type { pop }
  /SA { setstrokeadjust }
  /OP { setoverprint }
  /BG { resolveidfunction setblackgeneration }
  /UCR { resolveidfunction setundercolorremoval }
  /TR { resolveidfunction settransfer }
  /HT {
    dup /Default eq {
      pop .setdefaultscreen
    } {
	%****** NOT FINISHED ******
      resolvehalftone sethalftone
    } ifelse
  }
  /HTP { aload pop sethalftonephase }
  /SM { setsmoothness }
  /Font { aload pop Tf }
  /LW { setlinewidth }
  /LC { setlinecap }
  /LJ { setlinejoin }
  /ML { setmiterlimit }
  /D { aload pop setdash }
  /FL { setflat }
  /RI { ri }
.dicttomark readonly def
/gs {			% <gsres> gs -
  Page /ExtGState rget {
    { oforce exch gsparamdict exch .knownget { exec } { pop } ifelse }
    forall
  } if
} bdef

% ---------------- Color setting ---------------- %

% The keys here are resolved (PostScript, not PDF) color space names.
/csncompdict mark
  /DeviceGray { pop 1 }
  /DeviceRGB { pop 3 }
  /DeviceCMYK { pop 4 }
  /CIEBasedA { pop 1 }
  /CIEBasedABC { pop 3 }
  /Separation { pop 1 }
  /DeviceN { 2 oget length }
.dicttomark readonly def

% Perhaps some of the values in the following need to be modified
% depending on the WhitePoint value....
/cslabinit mark
  /DecodeABC [{16 add 116 div} bind {500 div} bind {200 div} bind]
  /MatrixABC [1 1 1 1 0 0 0 0 -1]
  /DecodeLMN [
    {dup 6 29 div ge {dup dup mul mul} {4 29 div sub 108 841 div mul} ifelse
     0.9505 mul} bind
    {dup 6 29 div ge {dup dup mul mul} {4 29 div sub 108 841 div mul} ifelse
     } bind
    {dup 6 29 div ge {dup dup mul mul} {4 29 div sub 108 841 div mul} ifelse
     1.0890 mul} bind
  ]
.dicttomark readonly def

/csrdict mark
  /DeviceGray {
    /DefaultGray Page /ColorSpace rget { exch pop resolvecolorspace } if
  }
  /DeviceRGB {
    /DefaultRGB Page /ColorSpace rget { exch pop resolvecolorspace } if
  }
  /DeviceCMYK { }
  /CalGray {
    1 oget dup /Gamma knownoget {
      exch dup length 1 add dict .copydict
      dup /DecodeA 4 -1 roll /exp load 2 packedarray cvx put
    } if
    /CIEBasedA exch 2 array astore
  }
  /CalRGB {
    1 oget dup /Gamma known 1 index /Matrix known or {
      dup length 2 add dict .copydict
      dup /Matrix knownoget { 1 index /MatrixABC 3 -1 roll put } if
      dup /Gamma knownoget {
        [ exch { /exp load 2 packedarray cvx } forall
        ] 1 index /DecodeABC 3 -1 roll put
      } if
    }
    if /CIEBasedABC exch 2 array astore 
  }
  /CalCMYK {
    pop /DeviceCMYK		% not defined by Adobe
  }
  /Lab {
    1 oget dup length 3 add dict .copydict
    dup /Range knownoget not { [-100 100 -100 100] } if
    [-100 0 null null null null] dup 2 4 -1 roll putinterval
    1 index /RangeABC 3 -1 roll put
    //cslabinit exch copy
    /CIEBasedABC exch 2 array astore
  }
  /ICCBased {
		% Since the PostScript interpreter doesn't support these yet,
		% always substitute an alternate space.
    dup /Alternate knownoget {
      exch pop
    } {
      /N get { null /DeviceGray null /DeviceRGB /DeviceCMYK } exch get
    } ifelse resolvecolorspace
  }
  /Separation {
    dup 2 2 copy oget resolvecolorspace put
    dup 3 oget resolvefunction
    1 index 3 3 -1 roll put
  }
  /DeviceN {
    dup 1 oget pop		% just force it
    dup 2 2 copy oget resolvecolorspace put
    dup 3 oget resolvefunction
    1 index 3 3 -1 roll put
  }
  /Indexed
   { dup 1 2 copy oget resolvecolorspace put
     dup 3 oget dup type /stringtype eq
      { pop
      }
      {		% The color lookup table is a stream.
		% Get its contents.  Don't lose our place in PDFfile.
	PDFfile fileposition 3 1 roll
	true resolvestream
	1 index 2 get 1 add
		% Stack: filepos cspace lookupstream len
	2 index 1 get	% basespace
	  dup dup type /arraytype eq { 0 get } if
	  //csncompdict exch get exec mul
	string readstring pop
		% Stack: filepos cspace table
	1 index 3 3 -1 roll put
	exch PDFfile exch setfileposition
      }
     ifelse
   }
  /Pattern
   { dup type /nametype ne
      { dup length 1 ge
	 { 1 get resolvecolorspace
	   /Pattern exch 2 array astore
	 }
	if
      }
     if
   }
.dicttomark readonly def

/cssubst {		% <csname> cssubst <cspace'> true
			% <csname> cssubst false
  dup resolvecolorspace
  dup 1 index ne { exch pop true } { pop pop false } ifelse
} bdef

/csresolve		% <csresourcename> csresolve <cspace>
 { dup Page /ColorSpace rget
    { exch pop resolvecolorspace }
    { /undefined cvx signalerror }
   ifelse
 } bdef
/resolvecolorspace {	% <cspace> resolvecolorspace <cspace'>
  dup dup type /arraytype eq { 0 get } if
  //csrdict exch .knownget {
    exec dup type /nametype ne { dup length 1 eq { 0 get } if } if
  } {
    csresolve
  } ifelse
} bdef

/scresolve	% <c0> ... scresolve <multi>
 {		% We can't really make sc[n] and SC[N] work, because
		% the color space information isn't available at
		% conversion time; so we hack it by assuming that
		% all the operands on the stack are used, and that
		% if the top operand is a name, it's a Pattern resource.
   dup type /nametype eq
    { Page /Pattern rget { resolvepattern } { null } ifelse }
   if
   count 1 gt
 } bdef
/resolvepattern		% <patternstreamdict> resolvepattern <patterndict>
 {		% Don't do the resolvestream now: just capture the data
		% from the file if necessary.
   dup length dict copy
   dup /FilePosition .knownget
    { 1 index /File get dup fileposition 3 1 roll
		% Stack: dict savepos pos file
      dup 3 -1 roll setfileposition
      dup 3 index /Length get string readstring pop
		% Stack: dict savepos file string
      3 1 roll exch setfileposition
      1 index /File 3 -1 roll put
      dup /FilePosition undef
    }
   if
   dup /PaintProc
    { false resolvestream pdfopdict .pdfrun
    }
   put
 } bdef

drawopdict begin
  /g { /DeviceGray cssubst { cs sc1 } { g } ifelse } bdef
  /rg { /DeviceRGB cssubst { cs sc* } { rg } ifelse } bdef
  /k { k } bdef
  /cs { csresolve cs } bdef
  /sc { scresolve { sc* } { sc1 } ifelse } bdef
  /scn /sc load def
  /G { /DeviceGray cssubst { CS SC1 } { G } ifelse } bdef
  /RG { /DeviceRGB cssubst { CS SC* } { RG } ifelse } bdef
  /K { K } bdef
  /CS { csresolve CS } bdef
  /SC { scresolve { SC* } { SC1 } ifelse } bdef
  /SCN /SC load def
end

% ---------------- Paths ---------------- %

drawopdict begin
			% Path construction
  /m /moveto load def
  /l /lineto load def
  /c /curveto load def
  /v { currentpoint 6 2 roll curveto } def
  /y { 2 copy curveto } def
  /re {
   4 2 roll moveto  exch dup 0 rlineto  0 3 -1 roll rlineto  neg 0 rlineto
   closepath
  } def
  /h /closepath load def
			% Path painting and clipping
  /n { n } def
  /S { S } def
  /s { s } def
  /f { f } def
  /f* { f* } def
  /B { B } def
  /b { b } def
  /B* { B* } def
  /b* { b* } def
  /W { W } def
  /W* { W* } def
end

% ---------------- XObjects ---------------- %

/xobjectprocs mark		% <dict> -proc- -
  /Image { DoImage }
  /Form { DoForm }
  /PS { DoPS }
.dicttomark readonly def

% Note that the keys in defaultdecodedict are resolved (PostScript, not PDF)
% color space names.
/01_1 [0 1] readonly def
/01_3 [0 1 0 1 0 1] readonly def
/01_4 [0 1 0 1 0 1 0 1] readonly def
/defaultdecodedict mark
  /DeviceGray { pop //01_1 }
  /DeviceRGB { pop //01_3 }
  /DeviceCMYK { pop //01_4 }
  /CIEBasedA { 1 get /RangeA .knownget not { //01_1 } if }
  /CIEBasedABC { 1 get /RangeABC .knownget not { //01_3 } if }
  /Separation { pop //01_1 }
  /DeviceN {
    dup 1 oget length [ exch {0 1} repeat ] readonly
  }
.dicttomark readonly def

/makeimagedict
 { dup length dict
   1 index /ColorSpace knownoget
    { resolvecolorspace
      dup type /arraytype eq { dup length 1 eq { 0 get } if } if
      exch begin /ColorSpace exch def
    }
    { begin
    }
   ifelse
   /ImageType 1 def
		% Always define ImageMask appropriately.
   dup /ImageMask knownoget dup { and } if
     /ImageMask exch def
   /Width 2 copy oget def
   /Height 2 copy oget def
   /BitsPerComponent 2 copy oget def
   /Decode 2 copy knownoget not
    {		% Decode is required for the PostScript image operators.
      ImageMask
       { [0 1]
       }
       { ColorSpace dup type /arraytype eq { 0 get } if dup /Indexed eq
	  { pop [ 0 1 BitsPerComponent bitshift 1 sub ] }
	  { defaultdecodedict exch get ColorSpace exch exec }
	 ifelse
       }
      ifelse
    }
   if def
   /Interpolate 2 copy knownoget { def } { pop } ifelse
   /ImageMatrix Width 0 0 Height neg 0 Height 6 array astore def
		% Even though we're going to read data,
		% pass false to resolvestream so that
		% it doesn't try to use Length (which may not be present).
   false resolvestream
     /DataSource exch def
  currentdict end
} bdef

/DoImage {
  makeimagedict
  dup /Mask knownoget {
    dup type /arraytype eq {
      1 index /ImageType 4 put
      1 index /MaskColor 3 -1 roll put
    } {
		% Mask is a stream, another Image XObject.
      makeimagedict
      4 dict begin
      /ImageType 3 def
      /InterleaveType 3 def
      /MaskDict exch def
      /DataDict exch def
      currentdict end
    } ifelse
  } if
  dup /ImageMask get
   { setfillcolor imagemask }
   { dup /ColorSpace get csset setcolorspace pop image }
  ifelse
} bdef

/DoForm {
  dup length dict copy
  dup [ /pop load 2 index /Resources knownoget { oforce } { 0 dict } ifelse
  3 index false /resolvestream cvx
  pdfopdict /.pdfruncontext cvx
  ] cvx /PaintProc exch put
  execform
} bdef

/DoPS {
  true resolvestream cvx exec
} bdef

drawopdict begin
  /Do
    { PDFfile fileposition exch
      dup Page /XObject rget not { /undefined cvx signalerror } if
      exch pop dup /Subtype get xobjectprocs exch get exec
      PDFfile exch setfileposition
    } bdef
end

% ---------------- In-line images ---------------- %

% Undo the abbreviations in an in-line image dictionary.
% Note that these can appear as keys, values, or members of array values.
% /I is ambiguous; we check specially for it below.
/unabbrevdict mark
	% Top-level dictionary keys
  /BPC /BitsPerComponent  /CS /ColorSpace  /D /Decode  /DP /DecodeParms
  /F /Filter  /H /Height  /IM /ImageMask  /W /Width
	% Values
  /AHx /ASCIIHexDecode  /A85 /ASCII85Decode  /CC /CalCMYK
  /CCF /CCITTFaxDecode  /CG /CalGray  /CR /CalRGB
  /DCT /DCTDecode  /CMYK /DeviceCMYK  /Fl /FlateDecode
  /G /DeviceGray  /RGB /DeviceRGB
  /I /Indexed  /LZW /LZWDecode  /RL /RunLengthDecode
.dicttomark readonly def
/unabbrev		% <obj> unabbrev <obj'>
 { dup type /nametype eq
    { unabbrevdict 1 index .knownget { exch pop } if
    }
    { dup type /arraytype eq
       { dup 0 1 2 index length 1 sub
	  { 2 copy get unabbrev put dup
	  }
	 for pop
       }
      if
    }
   ifelse
 } bdef

drawopdict begin
  /BI { mark } bdef
  /ID
    { counttomark
       { counttomark 1 roll
	 dup /I eq { pop /Interpolate } { unabbrev } ifelse
       }
      repeat
      /File PDFsource
      .dicttomark DoImage
      PDFsource token pop /EI ne { /ID cvx /syntaxerror signalerror } if
    } bdef
end

% ================================ Text ================================ %

drawopdict begin
			% Text control
  /BT { BT } def
  /ET { ET } def
  /Tc { Tc } def
  /TL { TL } def
  /Tr { Tr } def
  /Ts { Ts } def
  /Tw { Tw } def
  /Tz { Tz } def
			% Text positioning
  /Td { Td } def
  /TD { TD } def
  /Tm { Tm } def
  /T* { T* } def
			% Text painting
  /Tj { Tj } def
  /' { ' } def
  /" { " } def
  /TJ { TJ } def
end

end			% pdfdict
end			% GS_PDF_ProcSet
.setglobal