File: pgfshade.sty

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\ProvidesPackage{pgfshade}[2004/10/08 ver 0.64]

% Copyright 2003 by Till Tantau <tantau@cs.tu-berlin.de>.
%
% This program can be redistributed and/or modified under the terms
% of the LaTeX Project Public License Distributed from CTAN
% archives in directory macros/latex/base/lppl.txt.

\RequirePackage{pgf}
\RequirePackage{xxcolor}

\DeclareOption{pdf}
{

  \def\pgfsys@horishading#1#2#3{%
    {%
      \pgf@parsefunc{#3}%
      \setbox\pgf@tempbox=\hbox to\pgf@max{\vbox to#2{\vfil\pdfliteral{/Sh sh}}\hfil}%
      \pgf@process{\pgfpoint{\pgf@max}{#2}}%
      \pdfxform resources {%
        /Shading << /Sh << /ShadingType 2
        /ColorSpace /DeviceRGB
        /Domain [\pgf@doma\space\pgf@domb]
        /Coords [\pgf@doma\space0 \pgf@domb\space0]
        /Function \pgf@pdfparsedfunction
        /Extend [false false] >> >>}\pgf@tempbox%
      \expandafter\xdef\csname @pgfshading#1!\endcsname{\noexpand\pdfrefxform\the\pdflastxform}% 
      }%
    }
  \def\pgfsys@vertshading#1#2#3{%
    {%
      \pgf@parsefunc{#3}%
      \setbox\pgf@tempbox=\hbox to#2{\vbox to\pgf@max{\vfil\pdfliteral{/Sh sh}}\hfil}%
      \pgf@process{\pgfpoint{#2}{\pgf@max}}%
      \pdfxform resources {%
        /Shading << /Sh << /ShadingType 2
        /ColorSpace /DeviceRGB
        /Domain [\pgf@doma\space\pgf@domb]
        /Coords [0 \pgf@doma\space0 \pgf@domb]
        /Function \pgf@pdfparsedfunction
        /Extend [false false] >> >>}\pgf@tempbox%
      \expandafter\xdef\csname @pgfshading#1!\endcsname{\noexpand\pdfrefxform\the\pdflastxform}%
      }%
    }
  \def\pgfsys@radialshading#1#2#3{%
    {%
      \pgf@parsefunc{#3}%
      \setbox\pgf@tempbox=\hbox to2\pgf@max{\vbox to2\pgf@max{\vfil\pdfliteral{/Sh sh}}\hfil}%
      \pgf@process{#2}%
      \pgf@xa=\pgf@x%
      \pgf@ya=\pgf@y%
      \pgf@process{\pgfpoint{\pgf@max}{\pgf@max}}%
      \advance\pgf@xa by \pgf@x%
      \advance\pgf@ya by \pgf@y%
      \pdfxform resources {%
        /Shading << /Sh << /ShadingType 3
        /ColorSpace /DeviceRGB
        /Domain [\pgf@doma\space\pgf@domb]
        /Coords [\pgfget{xa} \pgfget{ya} \pgf@doma\space \pgfget x
        \pgfget y \pgf@domb]
        /Function \pgf@pdfparsedfunction
        /Extend [true false] >> >>}\pgf@tempbox%
      \expandafter\xdef\csname @pgfshading#1!\endcsname{\noexpand\pdfrefxform\the\pdflastxform}%
      }%
    }%
  }

\DeclareOption{postscript}
{
  \def\pgfsys@horishading#1#2#3{%
    {%
      \pgf@parsefunc{#3}%
      \setlength\pgf@x{#2}%
      \pgf@bpcorr{\pgf@x}%
      \expandafter\xdef\csname @pgfshading#1!\endcsname{\hbox{%
        \noexpand\begin{pgfpicture}{0pt}{0pt}{\the\pgf@max}{#2}%
          \noexpand\pgfrect[clip]{\noexpand\pgforigin}{\noexpand\pgfpoint{\the\pgf@max}{#2}}%
          \noexpand\pgf@ps{\pgf@domb\space \pgfget{x} pgfH \pgf@psfuncs\space pop}%
        \noexpand\end{pgfpicture}}}%
      }%
    }
  \def\pgfsys@vertshading#1#2#3{%
    {%
      \pgf@parsefunc{#3}%
      \setlength\pgf@x{#2}%
      \pgf@bpcorr{\pgf@x}%
      \expandafter\xdef\csname @pgfshading#1!\endcsname{\hbox{%
        \noexpand\begin{pgfpicture}{0pt}{0pt}{#2}{\the\pgf@max}%
          \noexpand\pgfrect[clip]{\noexpand\pgforigin}{\noexpand\pgfpoint{#2}{\the\pgf@max}}%
          \noexpand\pgf@ps{\pgf@domb\space \pgfget{x} pgfV \pgf@psfuncs\space pop}%
        \noexpand\end{pgfpicture}}}%
      }%
    }
  \def\pgfsys@radialshading#1#2#3{%
    {%
      \pgf@parsefunc{#3}%
      \pgf@process{#2}%
      \pgf@xa=2\pgf@max%
      \pgf@bpcorr{\pgf@max}%
      \advance\pgf@x by \pgf@max%
      \advance\pgf@y by \pgf@max%
      \expandafter\xdef\csname @pgfshading#1!\endcsname{\hbox{%
        \noexpand\begin{pgfpicture}{0pt}{0pt}{\the\pgf@xa}{\the\pgf@xa}%
          \noexpand\pgf@ps{%
            \pgf@domb\space \pgfget{y} \pgfget{x} \pgfget{max} pgfR1
            \pgf@psfuncs\space \pgf@firstcolor\space \pgf@doma\space pgfR2}%
        \noexpand\end{pgfpicture}}}%
      }%
    }
    
  % Parameters to horizontal pre axishade: \pgf@domb x
  \special{! /pgfH{%
      /pgfheight exch def 0.75 setlinewidth [] 0 setdash
      /pgfshade {pgfA} def /pgfdir { dup 0 moveto
        dup 5 index lineto } bind def} B}%
    
  % Parameters to vertical pre axishade: \pgf@domb x
  \special{! /pgfV{%
      /pgfheight exch def 0.75 setlinewidth [] 0 setdash
      /pgfshade {pgfA} def /pgfdir { dup 0 exch moveto dup 5 index
        exch lineto } bind def} B}%
    
  % Parameters to axishade: end x, start x, r-, g-, b- of first color, r-, g-, b- of second color
  % Stack afterwards: end x
  \special{! /pgfA{
      /pgfdiff 8 index round cvi 8 index round cvi sub 2 mul 1 add def
      2 index 6 index sub pgfdiff div % put red-step on stack
      2 index 6 index sub pgfdiff div % put green-step on stack
      2 index 6 index sub pgfdiff div % put green-step on stack
      pgfheight 9 index 9 index 9 index 14 index
      pgfdiff {
        3 index 3 index 3 index setrgbcolor % Set color
        pgfdir
        stroke
        4 -1 roll 7 index add % red += incred
        4 -1 roll 6 index add % green += incgreen
        4 -1 roll 5 index add % blue += incblue
        4 -1 roll .5 sub % x += 0.5
      } repeat      
      mark 15 1 roll cleartomark exch pop % leave only start x on stack
      }B }

  % Parameters to radialshade pre: \pgf@domb y x max
  \special{! /pgfR1{
    newpath dup dup dup 0 360 arc clip newpath
    dup /pgfendx exch def
    /pgfendy exch def
    0.875 setlinewidth
    [] 0 setdash
    /pgfshade {pgfR} def
    /pgfstartx exch def
    /pgfstarty exch def
    /pgfdiffx pgfendx pgfstartx sub def
    /pgfdiffy pgfendy pgfstarty sub def
    dup /pgfdomb exch def
    }B }

  % Parameters to radialshade post: \pgf@firstcolor \pgf@doma
  \special{! /pgfR2{ 
    newpath 0.5 add pgfcircx pgfcircy 3 2 roll 0 360 arc
    setrgbcolor fill pop}B }%

  % Parameters to radialshade: end x, start x, r-, g-, b- of first color, r-, g-, b- of second color
  % Stack afterwards: end x
  \special{! /pgfR{
      /pgfdiff 8 index round cvi 8 index round cvi sub 4 mul 1 add def
      /pgfcircx pgfstartx 9 index pgfdiffx pgfdomb div mul add def
      /pgfcircy pgfstarty 9 index pgfdiffy pgfdomb div mul add def
      /pgfcircxe pgfstartx 8 index pgfdiffx pgfdomb div mul add def
      /pgfcircye pgfstarty 8 index pgfdiffy pgfdomb div mul add def
      /pgfxstep pgfcircxe pgfcircx sub pgfdiff div def
      /pgfystep pgfcircye pgfcircy sub pgfdiff div def
      2 index 6 index sub pgfdiff div % put red-step on stack
      2 index 6 index sub pgfdiff div % put green-step on stack
      2 index 6 index sub pgfdiff div % put green-step on stack
      8 index 8 index 8 index 13 index
      pgfdiff {
        3 index 3 index 3 index setrgbcolor % Set color
        pgfcircx pgfcircy 2 index 0 360 arc closepath
        stroke
        4 -1 roll 6 index add % red += incred
        4 -1 roll 5 index add % green += incgreen
        4 -1 roll 4 index add % blue += incblue
        4 -1 roll .25 sub % x += 0.25
        /pgfcircx pgfcircx pgfxstep add def
        /pgfcircy pgfcircy pgfystep add def
      } repeat      
      mark 14 1 roll cleartomark exch pop % leave only start x on stack
      }B}
  }

\ProcessOptions


%
% Parsing functions
%
\newdimen\pgf@max
\def\pgf@parsefunc#1{%
  \edef\temp{{#1}}%
  \expandafter\pgf@convertrgbstring\temp%
  \edef\temp{{\pgf@rgbconv}}%
  \expandafter\pgf@@parsefunc\temp}
\def\pgf@@parsefunc#1{%
  \def\pgf@bounds{}%
  \def\pgf@funcs{}%
  \def\pgf@psfuncs{}%
  \def\pgf@encode{}%
  \pgf@parsefirst[#1; ]%
  \pgf@parselastdom[#1; ]%
  \pgf@parsemid[#1; ]%
  \edef\pgf@pdfparsedfunction{%
    << /FunctionType 3 /Domain [\pgf@doma\space\pgf@domb] /Functions
    [\pgf@funcs\space] /Bounds [\pgf@bounds] /Encode [0 1 \pgf@encode]
    >> }%
  \xdef\pgf@psfuncs{\pgf@psfuncs}%
  }
\def\pgf@parsefirst[rgb(#1)=(#2,#3,#4)#5]{%
  \setlength\pgf@x{#1}%
  \pgf@bpcorr\pgf@x%
  \edef\pgf@doma{\pgfget x}%
  \edef\pgf@prevx{\pgfget x}%
  \pgf@getrgbtuplewithmixin{#2}{#3}{#4}%
  \edef\pgf@prevcolor{\pgf@rgb}%
  \edef\pgf@firstcolor{\pgf@rgb}}
\def\pgf@parselastdom[rgb(#1)=(#2,#3,#4); {%
  \@ifnextchar]{%
    \setlength\pgf@x{#1}%
    \pgf@max=\pgf@x\relax%
    \pgf@bpcorr\pgf@x%
    \edef\pgf@domb{\pgfget x}%
    \@gobble}{\pgf@parselastdom[}}
\def\pgf@parsemid[rgb(#1)=(#2,#3,#4); {\pgf@parserest[}
\def\pgf@parserest[rgb(#1)=(#2,#3,#4); {%
  \@ifnextchar]{%
    \pgf@getrgbtuplewithmixin{#2}{#3}{#4}%
    \edef\pgf@funcs{\pgf@funcs\space%
      << /FunctionType 2 /Domain [\pgf@doma\space\pgf@domb] /C0
      [\pgf@prevcolor] /C1 [\pgf@rgb] /N 1 >> }%
    \edef\pgf@psfuncs{\pgf@prevx\space \pgf@rgb\space \pgf@prevcolor\space pgfshade \pgf@psfuncs}%
    \@gobble}{%
    \setlength\pgf@x{#1}%
    \pgf@bpcorr\pgf@x%
    \pgf@getrgbtuplewithmixin{#2}{#3}{#4}%
    \edef\pgf@psfuncs{\pgf@prevx\space \pgf@rgb\space \pgf@prevcolor\space pgfshade \pgf@psfuncs}%
    \edef\pgf@prevx{\pgfget{x}}%
    \edef\pgf@bounds{\pgf@bounds\space\pgfget x}%
    \edef\pgf@encode{\pgf@encode\space0 1}%
    \edef\pgf@funcs{\pgf@funcs\space%
      << /FunctionType 2 /Domain [\pgf@doma\space\pgf@domb] /C0
      [\pgf@prevcolor] /C1 [\pgf@rgb] /N 1 >> }% 
    \edef\pgf@prevcolor{\pgf@rgb}%
    \pgf@parserest[}}

\def\pgf@getrgbtuplewithmixin#1#2#3{%
  \definecolor{pgfshadetemp}{rgb}{#1,#2,#3}%
  \applycolormixins{pgfshadetemp}%
  \extractcolorspec{pgfshadetemp}{\pgf@tempcolor}%
  \expandafter\convertcolorspec\pgf@tempcolor{rgb}{\pgf@rgbcolor}%
  \expandafter\pgf@getrgb@@\pgf@rgbcolor!}
\def\pgf@getrgb@@#1,#2,#3!{%
  \def\pgf@rgb{#1 #2 #3}}


\def\pgf@convertrgbstring#1{%
  \def\pgf@rgbconv{}%
  \pgf@converttorgb#1]%
  }
\def\pgf@converttorgb{%
  \@ifnextchar]{\@gobble}%done!
  {%
    \@ifnextchar;{\pgf@grabsemicolor}%
    {%
      \@ifnextchar r{\pgf@grabrgb}%
      {%
        \@ifnextchar g{\pgf@grabgray}%
        {%
          \@ifnextchar c{\pgf@grabcolor}%
          {\PackageError{pgfshade}{Illformed shading
              specification}{}\pgf@converttorgb}%
        }%
      }%
    }%
  }%
}
\def\pgf@grabsemicolor;{%
  \edef\pgf@rgbconv{\pgf@rgbconv; }\pgf@converttorgb}
\def\pgf@grabrgb rgb(#1)=(#2,#3,#4){%
  \edef\pgf@rgbconv{\pgf@rgbconv rgb(#1)=(#2,#3,#4)}\pgf@converttorgb}
\def\pgf@grabgray gray(#1)=(#2){%
  \edef\pgf@rgbconv{\pgf@rgbconv rgb(#1)=(#2,#2,#2)}\pgf@converttorgb}
\def\pgf@grabcolor color(#1)=(#2){%
  \colorlet{pgf@tempcol}{#2}%
  \extractcolorspec{pgf@tempcol}{\pgf@tempcolor}%
  \expandafter\convertcolorspec\pgf@tempcolor{rgb}{\pgf@rgbcolor}%
  \expandafter\pgf@convgetrgb@\expandafter{\pgf@rgbcolor}{#1}%
}
\def\pgf@convgetrgb@#1#2{%
  \edef\pgf@rgbconv{\pgf@rgbconv rgb(#2)=(#1)}\pgf@converttorgb}




% Declares a horizontal shading for later use. The shading is a
% horizontal bar that changes its color.
%
% #1 = name of the shading for later use
% #2 = height of the shading
% #3 = color specification in the following format: A list of colors
%      that the bar should have at certain points. If the bar should
%      be red at 1cm, this is specified as
%      "rgb(1cm)=(1,0,0)". Multiple specifications are separated by a
%      semicolon and a space. At least two specifications must be
%      given. The specified positions must be given in increasing
%      order. 
%
% Example:
%
% \pgfdeclarehorizontalshading{redtogreentoblue}{1cm}{%
%   rgb(0cm)=(1,0,0); % red
%   rgb(1cm)=(0,1,0); % green
%   rgb(2cm)=(0,0,1)}
%
% \begin{document}
%   The following bar is 2cm long: \pgfuseshading{redtogreentoblue}.
% \end{document}

\newcommand\pgfdeclarehorizontalshading[4][]{%
  \expandafter\def\csname pgf@deps@pgfshading#2!\endcsname{#1}%
  \expandafter\ifx\csname pgf@deps@pgfshading#2!\endcsname\@empty%
    \pgfsys@horishading{#2}{#3}{#4}%
  \else%
    \expandafter\def\csname pgf@func@pgfshading#2!\endcsname{\pgfsys@horishading}%
    \expandafter\def\csname pgf@args@pgfshading#2!\endcsname{{#3}{#4}}%
    \expandafter\let\csname @pgfshading#2!\endcsname=\@empty%
  \fi}


% Declares a vertical shading for later use. 
%
% #1 = name of the shading for later use
% #2 = height of the shading
% #3 = color specification 
%
% Example:
%
% \pgfdeclareverticalshading{redtogreentoblue}{1cm}{%
%   rgb(0cm)=(1,0,0); % red
%   rgb(1cm)=(0,1,0); % green
%   rgb(2cm)=(0,0,1)}
%
% \begin{document}
%   The following bar is 2cm high: \pgfuseshading{redtogreentoblue}.
% \end{document}

\newcommand\pgfdeclareverticalshading[4][]{%
  \expandafter\def\csname pgf@deps@pgfshading#2!\endcsname{#1}%
  \expandafter\ifx\csname pgf@deps@pgfshading#2!\endcsname\@empty%
    \pgfsys@vertshading{#2}{#3}{#4}%
  \else%
    \expandafter\def\csname pgf@func@pgfshading#2!\endcsname{\pgfsys@vertshading}%
    \expandafter\def\csname pgf@args@pgfshading#2!\endcsname{{#3}{#4}}%
    \expandafter\let\csname @pgfshading#2!\endcsname=\@empty%
  \fi}


% Declares a radial shading for later use. 
%
% #1 = name of the shading for later use
% #2 = center of inner circle
% #3 = color specification 
%
% Description:
%
% A radial shading creates a smooth color transition between two
% circles. The center of the inner circle is at the give position. Its
% radius is the start of the color specification. The
% center of the outer circle is at the center of the whole shading,
% whose radius is the end of the color specification. For example,
% suppose the color specification is "rgb(1cm)=(1,1,1); rgb(2cm)=(0,0,0)".  
% Then the shading would be 4cm times 4cm large. The inner circle would
% have diameter 1cm and the outer circle would have diameter 2cm. The
% outer circle would be centered in the middle of the shading, whereas
% the outer circle would be centered at the given position.
%
% Example:
%
% \pgfdeclareradialshading{redtogreentoblue}{\pgfpoint{2cm}{2cm}}{%
%   rgb(10pt)=(1,0,0); % red
%   rgb(2cm)=(0,1,0); % green
%   rgb(3cm)=(0,0,1)}
%
% \begin{document}
%   The following ball has diameter 3cm: \pgfuseshading{redtogreentoblue}.
% \end{document}

\newcommand\pgfdeclareradialshading[4][]{%
  \expandafter\def\csname pgf@deps@pgfshading#2!\endcsname{#1}%
  \expandafter\ifx\csname pgf@deps@pgfshading#2!\endcsname\@empty%
    \pgfsys@radialshading{#2}{#3}{#4}%
  \else%
    \expandafter\def\csname pgf@func@pgfshading#2!\endcsname{\pgfsys@radialshading}%
    \expandafter\def\csname pgf@args@pgfshading#2!\endcsname{{#3}{#4}}%
    \expandafter\let\csname @pgfshading#2!\endcsname=\@empty%
  \fi}
  

% Inserts a box into the text that contains a previously defined
% shading. 
%
% #1 = Name of a shading
%
% Example:
%
% \pgfuseshading{redtogreentoblue}

\def\pgfuseshading#1{%
  \edef\pgf@shadingname{@pgfshading#1}%
  \pgf@tryextensions{\pgf@shadingname}{\pgfalternateextension}%
  \expandafter\@ifundefined\expandafter{\pgf@shadingname}%
  {\PackageError{pgfshade}{Undefined shading "#1"}{}}%
  {%
    {%
      \globalcolorsfalse%
      \def\pgf@shade@adds{}%
      \@ifundefined{pgf@deps\pgf@shadingname}%
      {}%
      {%
        \edef\@list{\csname pgf@deps\pgf@shadingname\endcsname}%
        \@for\@temp:=\@list\do{%
          {%
            \applycolormixins{\@temp}%
            \extractcolorspec{\@temp}{\pgf@tempcolor}%
            \expandafter\convertcolorspec\pgf@tempcolor{rgb}{\pgf@rgbcolor}%
            \xdef\pgf@shade@adds{\pgf@shade@adds,\pgf@rgbcolor}%
          }%
        }%
      }%
      \expandafter\pgf@strip@shadename\pgf@shadingname!!%
      \@ifundefined{@pgfshading\pgf@basename\pgf@shade@adds!}%
      {%
        {%
          \expandafter\def\expandafter\@temp\expandafter{\csname pgf@func\pgf@shadingname\endcsname}%
          \edef\@args{{\pgf@basename\pgf@shade@adds}}%
          \expandafter\expandafter\expandafter\def%
          \expandafter\expandafter\expandafter\@@args%
          \expandafter\expandafter\expandafter{\csname pgf@args\pgf@shadingname\endcsname}%
          \expandafter\expandafter\expandafter\@temp\expandafter\@args\@@args%
          %
        }%
      }%
      {}%
      \csname @pgfshading\pgf@basename\pgf@shade@adds!\endcsname%
    }%
  }%
}

\def\pgf@strip@shadename @pgfshading#1!!!{\def\pgf@basename{#1}}


% Create an alias name for a shading
%
% #1 = name of the alias
% #2 = name of the original
%
% Example:
%
% \pgfaliasshading{shading!25}{shadingshaded}

\def\pgfaliasshading#1#2{%
  \expandafter\let\expandafter\pgf@temp\expandafter=\csname @pgfshading#2!\endcsname%
  \expandafter\let\csname @pgfshading#1!\endcsname=\pgf@temp%
  \expandafter\let\expandafter\pgf@temp\expandafter=\csname pgf@deps@pgfshading#2!\endcsname%
  \expandafter\let\csname pgf@deps@pgfshading#1!\endcsname=\pgf@temp%
  \expandafter\let\expandafter\pgf@temp\expandafter=\csname pgf@func@pgfshading#2!\endcsname%
  \expandafter\let\csname pgf@func@pgfshading#1!\endcsname=\pgf@temp%
  \expandafter\let\expandafter\pgf@temp\expandafter=\csname pgf@args@pgfshading#2!\endcsname%
  \expandafter\let\csname pgf@args@pgfshading#1!\endcsname=\pgf@temp%
  }


\endinput