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%\iffalse -*-mode:Latex;tex-command:"latex *;dvips -D600 pst-blur -o"-*- \fi
%\iffalse
% $Id: pst-blur.dtx,v 2.0 2005/09/08 09:48:33 giese Exp $
%
% Copyright 1998 Martin Giese, giese@ira.uka.de
% 2005 Herbert Voss, voss@pstricks.de
%
% This file is distributed in the hope that it will be useful,
% but WITHOUT ANY WARRANTY; without even the implied warranty of
% MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
%
% IMPORTANT COPYRIGHT NOTICE:
%
% Permission is granted to copy this file to another file with a clearly
% different name and to customize the declarations in that copy to serve
% the needs of your installation, provided that you comply with
% the conditions in the file legal.txt from the LaTeX2e distribution.
%
% However, NO PERMISSION is granted to produce or to distribute a
% modified version of this file under its original name.
%
% You are NOT ALLOWED to change this file.
%
%\fi
%\iffalse
%<*driver>
\NeedsTeXFormat{LaTeX2e}
\documentclass{ltxdoc}
\usepackage{pst-char}
\usepackage{pst-node}
\usepackage{url}
\usepackage{pst-blur}
\AtBeginDocument{
% \OnlyDescription % comment out for implementation details
\EnableCrossrefs
\RecordChanges
\CodelineIndex}
\AtEndDocument{
\PrintChanges
\PrintIndex}
\hbadness=7000 % Over and under full box warnings
\hfuzz=3pt
\MakeShortVerb{\|}
\newcommand\file[1]{\texttt{#1}}
\begin{document}
\DocInput{pst-blur.dtx}
\end{document}
%</driver>
%\fi
%
% \CharacterTable
% {Upper-case \A\B\C\D\E\F\G\H\I\J\K\L\M\N\O\P\Q\R\S\T\U\V\W\X\Y\Z
% Lower-case \a\b\c\d\e\f\g\h\i\j\k\l\m\n\o\p\q\r\s\t\u\v\w\x\y\z
% Digits \0\1\2\3\4\5\6\7\8\9
% Exclamation \! Double quote \" Hash (number) \#
% Dollar \$ Percent \% Ampersand \&
% Acute accent \' Left paren \( Right paren \)
% Asterisk \* Plus \+ Comma \,
% Minus \- Point \. Solidus \/
% Colon \: Semicolon \; Less than \<
% Equals \= Greater than \> Question mark \?
% Commercial at \@ Left bracket \[ Backslash \\
% Right bracket \] Circumflex \^ Underscore \_
% Grave accent \` Left brace \{ Vertical bar \|
% Right brace \} Tilde \~}
% \CheckSum{152}
%
%
% \changes{v2.00}{2005/09/08}{%
% using the extended pst-xkey instead of the old pst-key package;
% creating a dtx file;
% new \LaTeX\ wrapper file (hv)}
% \changes{v1.80}{2001/02/16}{First public release. (mg)}
%
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% \DoNotIndex{\eCN,\edef,\else,\eHd,\eMcj,\EnableCrossrefs,\end,\endcsname}
% \DoNotIndex{\endCenterExample,\endExample,\endinput,\endpsclip}
% \DoNotIndex{\PrintIndex,\PrintChanges,\ProvidesFile}
% \DoNotIndex{\endpspicture,\endSideBySideExample,\Example}
% \DoNotIndex{\F,\f,\FdUrr,\fi,\filedate,\fileversion,\FV@Environment}
% \DoNotIndex{\FV@UseKeyValues,\FV@XRightMargin,\FVB@Example,\fvset}
% \DoNotIndex{\G,\g,\GetFileInfo,\gr,\GradientLoaded,\gsFKrbK@o,\gsj,\gsOX}
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% \DoNotIndex{\chardef,\loop,\leavevmode,\ifnum,\lower,\next,\wd,\setbox}
% \setcounter{IndexColumns}{2}
%
% \title{\textsf{pst-blur} package \\ version \fileversion}
% \author{Martin Giese\thanks{\protect\url{giese@ira.uka.de}} and
% Herbert Voss\thanks{\protect\url{voss@pstricks.de}}}
% \date{\filedate}
% \maketitle
%
%\section{Introduction}
% The ability to paint shadows on arbitrary shapes is a standard
% feature of PSTricks. However, these shadows are always `hard':\\
%{\psset{unit=0.6cm,linewidth=0.5pt}
% \begin{pspicture}(-5,0)(10,4)
% \psset{shadow=true,shadowcolor=gray,shadowsize=0.15cm}
% \psframe(1,1)(3,3)
% \pscircle(6,2){1}
% \rput(9,2){\pscharpath{\fontfamily{ptm}\fontsize{40}{40}\selectfont A}}
% \end{pspicture}
%}\\
% The |pst-blur| package provides blurred shadows
% for closed shapes drawn with PSTricks:\\
%{\psset{unit=0.6cm,linewidth=0.5pt,blur=true,blurradius=0.07cm}
% \begin{pspicture}(-5,0)(10,4)
% \psset{shadow=true,shadowcolor=gray,shadowsize=0.15cm}
% \psframe(1,1)(3,3)
% \pscircle(6,2){1}
% \rput(9,2){\pscharpath{\fontfamily{ptm}\fontsize{40}{40}\selectfont A}}
% \end{pspicture}
%}\\
% It also provides a new
% box command |\psblurbox|, which is similar to |\psshadowbox|,
% but gives the box a blurred shadow.
% \medskip
%
%The new graphics parameters and macros provided by the package
% are described in
%section 2 of this document. Section 3, if present, documents the
%implementation consisting of a generic \TeX\ file and a PostScript
%header for the |dvi|-to-PostScript converter. You can get section 3
%by calling \LaTeX\ as follows on most relevant systems:
%\begin{verbatim}
%latex '\AtBeginDocument{\AlsoImplementation}\input{pst-blur.dtx}'
%\end{verbatim}
%
%\section{Package Usage}
% To use |pst-blur|, you have to say
% \begin{verbatim}
% \usepackage{pst-blur}
% \end{verbatim}
% in the document prologue for \LaTeX, and
% \begin{verbatim}
% \input pst-blur.tex
% \end{verbatim}
% in ``plain'' \TeX.
%
% \DescribeMacro{blur}
% To paint shapes with blurred shadows,
% set the graphics parameters |shadow| and |blur| to |true|, eg
% \pscircle[shadow=true,blur=true](8,-0.5){0.5}
% \begin{verbatim}
% \psset{unit=1cm}
% \pscircle[shadow=true,blur=true](0,0){0.5}
% \end{verbatim}
% \psset{unit=1cm}
% for a circle with a blurred shadow.
% The parameter |blur| has no influence if |shadow| is |false|.
% \medskip
%
% \DescribeMacro{shadowsize}
% \DescribeMacro{shadowangle}
% \DescribeMacro{blurradius}
% The rendering of blurred shadows is controlled by a number of
% additional graphics parameters. The offset of the shadow is controlled
% by the parameters |shadowsize| and |shadowangle|, which are the same
% as for ordinary shadows.\footnote{In particular, |shadowangle| has
% to be negative for the usual placement of shadows below and to the
% right of shapes.} The size of the blurring effect is
% controlled by the parameter |blurradius|, see Fig~\ref{fig:params}.
% The default value for |blurradius| is 1.5pt, which fits nicely with
% the default |shadowsize| of 3pt.
% \medskip
%
% \begin{figure}\caption{Parameters for blurred shadows}
% \label{fig:params}
% \vskip1cm
% \qquad\qquad\begin{pspicture*}(0,0)(10,6)
% \psframe[linewidth=4pt,fillcolor=lightgray,fillstyle=crosshatch,
% shadow=true,blur=true,shadowsize=2cm,shadowangle=-35,
% blurradius=1cm,shadowcolor=lightgray](-5,3)(5,10)
% \pnode(5,3){A}
% \pnode(5.3,2.9){A1}
% \pnode(6.64,1.85){B}
% \pnode(7.51,2.35){C}
% \pscircle(6.64,1.85){1}
% \ncline{|-|}{A}{B}
% \bput(0.2){|shadowsize|}
% \ncline{->}{B}{C}
% \bput(1.5){|blurradius|}
% \psline(5,3)(6,3)
% \psarcn{->}(5,3){0.5}{0}{-35}
% \rput(7,3.7){\rnode{D}{$-|shadowangle|$}}
% \nccurve[linewidth=0.5pt,angleA=-90,angleB=70]{->}{D}{A1}
% \rput[l](6,5.6){|shadowcolor|}
% \rput[l](8,5){|blurbg|}
% {\psset{linestyle=dotted}
% \psline(0,0.85)(6.64,0.85)
% \psline(7.64,1.85)(7.64,6)
% \psset{linestyle=dashed}
% \psline(0,2.85)(5.64,2.85)
% \psline(5.64,2.85)(5.64,6)}
% {\psset{linewidth=0.5pt}
% \psline{*-}(5.64,5.3)(6,5.4)
% \psline{*-}(7.64,4.75)(8,4.85)
% \ncline{F}{F1}
% }
% \end{pspicture*}
% \end{figure}
%
% \DescribeMacro{shadowcolor}
% \DescribeMacro{blurbg}
% The inner, usually darkest part of the shadow is painted in the
% colour defined by |shadowcolor|. In the range defined by |blurradius|,
% the colour gradually fades to the background colour set by |blurbg|.
% The default value for |blurbg| is white. You should change this parameter
% when you want to paint shapes over a coloured background, ie\\
% \begin{minipage}{\textwidth}
% \begin{verbatim}
% \psframe[fillstyle=solid,fillcolor=yellow](-.7,-.7)(.7,.7)
% \pscircle[shadow=true,blur=true,blurbg=yellow](0,0){0.4}
% \end{verbatim}
% \rput(11.7,1.4){
% \psframe[fillstyle=solid,fillcolor=yellow](-.7,-.7)(.7,.7)
% \pscircle[shadow=true,blur=true,blurbg=yellow](0,0){0.4}}
% \end{minipage}
%
% \DescribeMacro{blursteps}
% The number of distinct colour steps painted between |shadowcolor|
% and |blurbg| is controlled by the parameter |blursteps|. The default
% value for |blursteps| is 20, which is usually more than sufficient.
% Note, that higher values for |blursteps| result in proportionally slower
% rendering. This can be very tiresome with complex shapes.
% \medskip
%
% \DescribeMacro{\psblurbox}
% Using a
% \psframebox[shadow=true,blur=true,blurradius=2.5pt,shadowcolor=gray]%
% {|\ttfamily\symbol{92}psframebox|}
% with a blurred
% shadow in the middle of some text produces poor results, because \TeX\
% does not know about the extra space taken by the shadow. For normal
% shadows, this problem is solved by the |\psshadowbox| macro, which
% adds the extra space around the box for the shadow. For blurred shadows,
% this is not sufficient: an extra |\blurradius| has to be added. This
% is done by the macro \psblurbox{\ttfamily\symbol{92}psblurbox}, which is otherwise
% identical to |\psshadowbox|. Note, that |\psblurbox| shares a
% deficiency of |\psshadowbox|: It only works correctly
% with $|shadowangle|=-45$, because \TeX\ does not provide trigonometric
% operations.
%
% \StopEventually{}
%
% \section{The Code}
%
% \subsection{The \file{pst-blur.sty} file}
% The \file{pst-blur.sty} file is very simple. It just loads
% the generic \file{pst-blur.tex} file.
% \begin{macrocode}
%<*stylefile>
\RequirePackage{pstricks}
\ProvidesPackage{pst-blur}[2005/09/08 package wrapper for
pst-blur.tex (hv)]
\input{pst-blur.tex}
\ProvidesFile{pst-blur.tex}
[\filedate\space v\fileversion\space `PST-blur' (hv)]
%</stylefile>
% \end{macrocode}
%
% \subsection{The \file{pst-blur.tex} file}
% \file{pst-blur.tex} contains the \TeX-side of things. We begin
% by identifying ourselves and setting things up, the same as in
% other PSTricks packages.
% \begin{macrocode}
%<*texfile>
\csname PstBlurLoaded\endcsname
\let\PstBlurLoaded\endinput
\ifx\PSTricksLoaded\endinput\else
\def\next{\input pstricks.tex }\expandafter\next
\fi
% \end{macrocode}
% \verb+pst-blur+ uses the extended version of the keyvalue interface.
% \begin{macrocode}
\ifx\PSTXKeyLoaded\endinput\else\input pst-xkey \fi
% \end{macrocode}
%%
% \begin{macrocode}
\def\fileversion{2.0}
\def\filedate{2005/09/08}
\message{ v\fileversion, \filedate}
\edef\TheAtCode{\the\catcode`\@}
\catcode`\@=11
% \end{macrocode}
% Add the package name to the list of family names of the keyvalue list.
% \begin{macrocode}
\pst@addfams{pst-blur}
\pstheader{pst-blur.pro}
% \end{macrocode}
%
% \subsubsection{New graphics parameters}
% \begin{macro}{blur}
% \begin{macro}{blurradius}
% \begin{macro}{blursteps}
% \begin{macro}{blurbg}
% The definitions of the new graphics parameters follow the definitions
% for parameters of the same types found in |pstricks.tex|.
% \begin{macrocode}
\newif\ifpsblur
\define@key[psset]{pst-blur}{blur}[true]{\@nameuse{psblur#1}\pst@setrepeatarrowsflag}
\psset{blur=false}
%%
\define@key[psset]{pst-blur}{blurradius}{\pst@getlength{#1}\psx@blurradius}
\psset{blurradius=1.5pt}
%%
\define@key[psset]{pst-blur}{blursteps}{\pst@getint{#1}\psx@blursteps}
\psset{blursteps=20}
%%
\define@key[psset]{pst-blur}{blurbg}{\pst@getcolor{#1}\psx@blurbg}
\psset{blurbg=white}
% \end{macrocode}
% \end{macro}
% \end{macro}
% \end{macro}
% \end{macro}
% \subsection{Hooking into the PSTricks shadow macros}
% \begin{macro}{\pst@closedshadow}
% The macro |\pst@closedshadow| is usually called internally by
% PSTricks to paint a shadow in the shape of the current path.
% This macro has been renamed |\pst@sharpclosedshadow|. The
% new |\pst@closedshadow| jumps to either of |\pst@sharpclosedshadow|
% or |\pst@blurclosedshadow|, depending on |\ifpsblur|, which is
% directly related to the graphics parameter |blur|.
% \begin{macrocode}
\def\pst@closedshadow{%
\ifpsblur\pst@blurclosedshadow\else\pst@sharpclosedshadow\fi
}
\def\pst@sharpclosedshadow{%
\addto@pscode{%
gsave
\psk@shadowsize \psk@shadowangle \tx@PtoC
\tx@Shadow
\pst@usecolor\psshadowcolor
gsave fill grestore
stroke
grestore
gsave
\pst@usecolor\psfillcolor
gsave fill grestore
stroke
grestore}}
% \end{macrocode}
% \end{macro}
% \begin{macro}{\pst@blurclosedshadow}
% The PostScript code for blurred shadows is produced by the following
% macro. It pushes the diverse parameters (|\tx@PtoC| does polar to
% cartesian coordinate transformation for the shadow offset) and calls
% |BlurShadow|. Afterwards, it fills and strokes the current path,
% same as the original |\pst@closedshadow|.
% \begin{macrocode}
\def\pst@blurclosedshadow{%
\addto@pscode{%
gsave
gsave \pst@usecolor\psshadowcolor currentrgbcolor grestore
gsave \pst@usecolor\psx@blurbg currentrgbcolor grestore
\psx@blurradius\space
\psx@blursteps\space
\psk@shadowsize \psk@shadowangle \tx@PtoC
tx@PstBlurDict begin BlurShadow end
grestore
gsave
\pst@usecolor\psfillcolor
gsave fill grestore
stroke
grestore}}
% \end{macrocode}
% \end{macro}
% \begin{macro}{\pst@blurclosedshadow}
% This one looks very impressing. In fact, it is a verbatim copy
% of |\psshadowbox|, with only the line
% |\advance\pst@dimh\psx@blurradius\p@| added!
% \begin{macrocode}
\def\psblurbox{%
\def\pst@par{}\pst@object{psblurbox}}
\def\psblurbox@i{\pst@makebox\psblurbox@ii}
\def\psblurbox@ii{%
\begingroup
\pst@useboxpar
\psblurtrue
\psshadowtrue
\psboxseptrue
\setbox\pst@hbox=\hbox{\psframebox@ii}%
\pst@dimh=\psk@shadowsize\p@
\pst@dimh=.7071\pst@dimh
\advance\pst@dimh\psx@blurradius\p@
\pst@dimg=\dp\pst@hbox
\advance\pst@dimg\pst@dimh
\dp\pst@hbox=\pst@dimg
\pst@dimg=\wd\pst@hbox
\advance\pst@dimg\pst@dimh
\wd\pst@hbox=\pst@dimg
\leavevmode
\box\pst@hbox
\endgroup}
%%
\catcode`\@=\TheAtCode\relax
%</texfile>
% \end{macrocode}
% \end{macro}
%
% \subsection{The \file{pst-blur.pro} file}
% The file \file{pst-blur.pro} contains PostScript definitions
% to be included in the PostScript output by the
% |dvi|-to-PostScript converter, eg |dvips|.
% This is all rather similar to
% \file{pst-slpe.pro}, and I just don't feel like explaining it,
% so you'll have to work through it yourself, if you want to
% know what happens. The trick is basically to draw the outline
% repeatedly with varying line widths. The procedure |Shadow|
% called in |BlurShadow| is defined in \file{pstricks.pro} and
% translates the current path based on an $x$- and $y$-displacement
% taken from the stack.
% \begin{macrocode}
%<*prolog>
/tx@PstBlurDict 60 dict def
tx@PstBlurDict begin
/Iterate {
/SegLines ED
/ThisB ED /ThisG ED /ThisR ED
/NextB ED /NextG ED /NextR ED
/W 2.0 BlurRadius mul def
/WDec W SegLines div def
/RInc NextR ThisR sub SegLines div def
/GInc NextG ThisG sub SegLines div def
/BInc NextB ThisB sub SegLines div def
/R ThisR def
/G ThisG def
/B ThisB def
SegLines {
R G B
sqrt 3 1 roll sqrt 3 1 roll sqrt 3 1 roll
setrgbcolor
gsave W setlinewidth
stroke grestore
/W W WDec sub def
/R R RInc add def
/G G GInc add def
/B B BInc add def
} bind repeat
} def
/BlurShadow {
Shadow
/BlurSteps ED
/BlurRadius ED
dup mul /BEnd ED dup mul /GEnd ED dup mul /REnd ED
dup mul /BBeg ED dup mul /GBeg ED dup mul /RBeg ED
RBeg REnd add 0.5 mul /RMid ED
GBeg GEnd add 0.5 mul /GMid ED
BBeg BEnd add 0.5 mul /BMid ED
/OuterSteps BlurSteps 2 div cvi def
/InnerSteps BlurSteps OuterSteps sub def
1 setlinejoin
RMid GMid BMid REnd GEnd BEnd OuterSteps Iterate
gsave RBeg sqrt GBeg sqrt BBeg sqrt setrgbcolor fill grestore
clip
0 setlinejoin
RMid GMid BMid RBeg GBeg BBeg InnerSteps Iterate
} def
end
%</prolog>
% \end{macrocode}
% \Finale
%
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