\newpsobject{usergrid}{psgrid}{subgriddiv=1,griddots=10,gridlabels=7pt} \iffalse \author{Sebastian Rahtz} \title{An introduction to PSTricks, part I} \begin{Article} aaaaa \end{Article} \endinput \fi \def\CurrentPackages{spqr,pstcol} \newcounter{myN} \setlongtables \author{Sebastian Rahtz} \title{An introduction to PSTricks, part I} \begin{Article} \section{Preface} In all the questions about \TeX\ and drawing that appear in \emph{fora} like \texttt{comp.text.tex}, surprisingly little attention is paid to what seems to me one of the most delightful macro packages available. This is \PST, which allows the \TeX\ user almost full access to the power of \PS, using the \verb|\special| mechanism. In this, and the following two issues of, \BV, I will attempt to offer a survey of what \PST\ can do, and perhaps persuade more \BV\ readers to experiment. This material is drawn from a forthcoming book by myself and Michel Goossens; we are grateful to Timothy van Zandt (the author of \PST) and Denis Girou (its best-known exponent) for the many helpful insights and examples which they have vouchsafed during the several years we have been working on the material. This first tutorial looks at the principles of \PST, and the basic building blocks; the next will consider nodes, trees, matrices and the like, and the final part will look at customising \PST\ and some programming examples. \section{Introduction} \PST\ consists of a core of picture drawing primitives implemented by \Special{}s which pass \PS\ through to a driver. It also contains a set of higher-level macros for particular applications. With it you can: \begin{enumerate} \item draw lines, polygons, circles and curves; \item place and manipulate \TeX\ text; \item plot data with complicated labelled axes; \item draw nodes and connectors (including trees); \item colour lines and fill objects; \item define new graphical commands. \end{enumerate} This is an extremely powerful package, and its facilities can take some time to understand. It is documented in \cite{Zandt:1993a}, and its implementation is described in \cite{Zandt-Girou:1994}. \cite{Girou:1994} provides an excellent demonstration of the abilities of the package, and I am grateful to Denis Girou for permission to reproduce some of his examples below. The package relies on the ability of a dvi driver to pass through literal \PS\ code, and know that it will interact with the \TeX\ text in a controlled way. The \Program{dvips} driver provides the reference implementation, but it works with other drivers (like Textures) as well. The \PST\ installation guide explains what a driver has to be able to do. \PST\ is not a tool for drawing just one type of diagram well, like so many of the other packages you can find on \textsc{ctan}. It is a programming environment for as close a combination of \TeX\ and \PS\ as is possible with existing software; its strength is its modularity, extensibility, and ability to access all the power of \PS. The main package, and the subsidiary ones, need access to various \PS\ header files; the user does not need to explicitly load them, but the driver must be capable of doing so. The method for loading header files, and other \Special{} communication, is defined by a configuration file. The majority of \PST\ is loaded in a single package, but some more complicated facilities need an extra file to be loaded: \begin{center} \begin{tabular}{ll} \emph{File} & \emph{Function}\\ \hline \texttt{pst-coil} & Coil and zigzag objects\\ \texttt{textpath} & Typesetting text on a path\\ \texttt{charpath} & Stroking and filling character paths\\ \texttt{pst-plot} & Data plotting\\ \texttt{pst-3d} & Three-dimensional drawing\\ \texttt{pst2eps} & Export of objects direct to EPS files\\ \texttt{pst-node} & Placing and joining nodes\\ \texttt{pstree} & Tree macros\\ \texttt{gradient} & Gradient colour fills\\ \hline \end{tabular} \end{center} In the descriptions that follow, we do \emph{not} normally indicate which file needs loading for a particular function, since this may change with new releases of the package. Most of the commands provided will draw some kind of object at specified coordinates, which are relative to the current point in \TeX. The objects do not usually take up any space, in \TeX\ terms; they can either be mixed in with normal commands, or used in a picture environment to construct a whole drawing. The \LaTeX\ environment corresponding to the command: \begin{quote} \PSTCom \pspicture`*[baseline](\x0,\y0)'\c1 \end{quote} is normally used for pictures; space is reserved in \TeX\ for a rectangle with corners at \c0 and \c1 (as in other cases, \c0 defaults to (0,0)). The * form clips graphic objects which appear outside the frame. By default, the baseline is set at the bottom of the box, but the optional argument "[baseline]" sets the baseline fraction "baseline" from the bottom. I will not attempt to describe absolutely every \PST\ macro, or give examples of all the possible combinations and tricks, as this would require a large book, so we strongly commend the reader to study the published examples by Denis Girou for ideas on \PST\ programming, as well as the manual itself. \subsection{Basic \protect\PST\ concepts} Luckily, almost all the commands have the same (complex) structure; they need some or all of the following arguments, each of which has its consistent delimiters: \noindent\begin{tabular}{@{}l@{}rl@{}} \emph{Type} & \emph{Delimiters} & \emph{Example} \\ \hline Obligatory parameter &curly brackets & \verb"{arg}" \\ Optional settings & square brackets & \verb"[par1=val1,".\,.\\ Coordinates & parentheses & \verb"(x,y)" \\ \end{tabular} Many macros can have a lot of arguments, so it is useful to know that you can leave a space or new line between arguments, except those enclosed in curly braces. The layout of a command is \begin{small} \begin{verbatim} \command*[settings]{arrows/parameters} (coordinates) \end{verbatim} \end{small} \begin{itemize} \item The * form of the command generally means that the object being drawn is to be solid, rather than an outline; \item The \emph{settings} are optional, and consists of a set of \emph{key=value} pairs which over-ride, for the current object, \PST's drawing defaults; this is discussed below; \item Many commands which draw lines have an argument which specifies whether, and how, arrow heads are to be drawn at either end; or they need an argument like a rotation angle; \item Most objects require one or more coordinates; these consist of two numbers separated by a comma; multiple coordinate pairs each have their own set of brackets. \end{itemize} A simple complete example is \begin{GridPSExample}(0,0)(2,2) \psline[linewidth=1pt,linecolor=gray] {<->}(0.5,0)(0,1)(1,1.5)(1.5,1)(.5,.5) \end{GridPSExample} where a grid has been superimposed to show the coordinate system. \subsubsection{Coordinates} By default the coordinate system is in units of 1cm in the $x$ and $y$ directions, but that can be simply overridden as we shall see in a moment. Coordinate pairs can not only be given in the default units, but also in any \TeX\ dimensions. This applies to all `quantity' settings, so \verb|linewidth=.5| means .5 of whatever the current unit is, but \verb|linewidth=2pt| is an absolute size. The command \Usage{SpecialCoor} lets you use polar coordinates, in the form "(;)", where is the radius (a dimension) and is the angle. You can still use Cartesian coordinates. The parameter actually sets the $x$ and $y$ parameters which can also be set individually, so that you can scale the $x$ and $y$ dimensions in Cartesian coordinates unevenly. Angles, in polar coordinates and other arguments, should be a number giving the angle in degrees, by default. You can also change the units used for angles with the command %%%%% put this at the end of a line and add a space after it!!!! \PSTCom \degrees`[num]' \ where is the number of units in a circle. Thus \begin{verbatim} \degrees[100] \end{verbatim} could be used when making a pie chart where the data values are supplied as percentages. The command \Lcs{radians} is short for "\degrees[6.28319]" \subsubsection{Colouring objects} \PST\ comes with its own collection of colour macros, which provide a basic set of colours, and allow one to define new colour names in terms of RGB, CMYK or HSB models; however, we recommend that \LaTeX\ users should stick with the \Lpack{color} package. The standard package and \PST\ can be used together by loading the package \Lpack{pstcol}, which comes with the colour and graphics bundle. The \Lpack{gradient} package adds facilities for gradations of colour in filled objects. The following colours are predefined:\\ "black", "darkgray", "gray", "lightgray", "white", "red", "green", "blue", "cyan", "magenta", and "yellow". \subsubsection{Setting graphics parameters} \PST\ uses a notation similar to that introduced for the \Lpack{graphicx} package, \ie `key=value' pairs. This is used for setting a large number of graphical parameters which apply to almost all objects. These can be set in two ways: \begin{enumerate} \item On a per-object basis, with the optional parameter in square brackets; in this case the effect is local to the object with no further grouping needed; \item Globally, using the \Lcs{psset} command. The syntax is: \begin{quote} \PSTCom \psset{par1=value1`,par2=value2,\ldots'} \end{quote} \end{enumerate} Extra spaces are only allowed following the comma that separates "=" pairs (which is therefore a good place to start a new line if you are giving a long list). A selection of the commoner graphics parameters that can be set for objects are listed in Table~\ref{PSTparms}; the first group can be applied to more or less anything, but the others only apply to a particular group. \begin{small} \begin{longtable}{llP{.5\textwidth}} \caption{\protect\PST\ Graphical parameters} \label{PSTparms}\\[1mm] \emph{Parameter} & \emph{Default} & \emph{Explanation}\\ \hline \endfirsthead \caption*{\protect\PST\ Graphical parameters \emph{cont.}}\\[1mm] \emph{Parameter} & \emph{Default} & \emph{Explanation}\\ \hline \endhead \mbox{}\\ \endfoot \multicolumn{3}{l}{\bfseries\itshape General}\\ \Par{unit=dim} (1cm) \\ \Par{xunit=dim} (1cm) \\ \Par{yunit=dim} (1cm) \\ \Par{linewidth=dim} (.8pt) \\ \Par{linecolor=colour} (black) \\ \Par{fillcolor=colour} (white) \\ \Par{fillstyle=style} (none)&{Other possibilities are solid, vlines, vlines*, hlines, hlines*, crosshatch and crosshatch*. The * versions also fill the background. The \Lpack{gradient} package adds the extra \emph{gradient} style for a graded fill, and the following keys.}\\ \Par{gradbegin=colour} ()&{The starting and ending colour of a graded fill} \\ \Par{gradend=colour} ()&{The colour at the midpoint.} \\ \Par{gradlines=int} (500)&{The number of lines in the graded fill. More lines means finer gradiation, but slower printing.}\\ \Par{gradmidpoint=num} (.9)&{The position of the midpoint, as a fraction of the distance from top to bottom (the will be between 0 and 1)}.\\ \Par{gradangle=angle} (0)&{The gradation is rotated by .} \\ \Par{hatchwidth=dim} (.8pt)&{Width of fill lines} \\ \Par{hatchsep=dim} (4pt)&{The gap between fill lines} \\ \Par{hatchcolor=colour} (black) \\ \Par{hatchangle=angle} (45) \\ \Par{arrows=style} (none) &The possibilities are listed in Table~\ref{PSTarrows}; any symbol, or none, can be put at either end of a line \\[6pt] \multicolumn{3}{l}{\bfseries\itshape Lines, curves and boxes}\\ \Par{linestyle=style} (solid)&{Other possibilities are \emph{dashed}, \emph{dotted} and \emph{none}} \\ \Par{dash=dim1 dim2} (5pt 3pt)&{The black/white dash pattern for dashed lines.} \\ \Par{dotsep=dim} (3pt) \\ \Par{doubleline=true/false} (false)&{Draw lines as double line, separated by \emph{bordersep} and with colour \emph{bordercolor} between the lines.} \\ \Par{doublesep=dim} (1.25 of linewidth) \\ \Par{shadow=true/false} (false)&{A shadow is drawn at angle \emph{shadowangle}, of depth \emph{shadowsize} and colour \emph{shadowcolor}.} \\ \Par{shadowsize=dim} (3pt) \\ \Par{shadowangle=angle} (-45) \\ \Par{shadowcolor=colour} (darkgray) \\ \Par{linearc=dim} (0pt)&{The radius of arcs drawn at the corners of a box or set of line segments.} \\ \Par{framearc=dim} (0pt)&{If \emph{cornersize} is `relative', then the radius of rounded corners of framing boxes is set to \emph{num} times the width of height of the frame, whichever is less. \emph{num} cannot be greater than 1. If \emph{cornersize} is `absolute', \emph{num} sets the radius of arcs of rounded corners.} \\ \Par{cornersize=relative/absolute} (relative) \\[6pt] \multicolumn{3}{l}{\bfseries\itshape Text frames}\\ \Par{framesep=dim} (3pt)&{The gap between a frame and the enclosed text} \\ \Par{boxsep=true/false} (true)&{Whether the \TeX\ box that is produced includes the size of the frame itself or not} \\[6pt] \multicolumn{3}{l}{\bfseries\itshape Dots}\\ \Par{dotstyle=style} (*)&The possible styles are listed in Table \ref{dotstyles} \\ \Par{dotsize=dim } (2pt 2)&The diameter of a circle or disc is \emph{dim} plus \emph{num} times the current linewidth \\ \hline \end{longtable} \end{small} \section{The graphic objects} We list in Table \ref{PSTbasic} the most common basic objects which \PST\ can draw; they all, with the exception of the text-framing commands, take up no \TeX\ space, and so should be used inside a \texttt{pspicture} environment when creating a free-standing picture. In almost every case, an initial first coordinate can be omitted, and defaults to $0,0$. Lines and open curves can optionally be terminated with various symbols, and it is this that the \texttt{arrows}\ldots styles set. \PST\ has two powerful commands for positioning (and rotating, if necessary) something, including normal \LaTeX\ material; they are analagous to \LaTeX's basic "\put" command. The more common command is \begin{quote} \PSTCom \rput*`[refpoint]{angle}'(\x0,\y0){stuff} \end{quote} The * form puts a "\psframebox" around , which effectively blocks out anything underneath. is rotated by if the argument is present; the it can be preceded by a "*", which has the effect of undoing all rotations in outer calls to \Usage{rput}. This is needed when placing text labels, to make it easy to place them consistently in the right orientation. Since many rotations are in steps of 90\degrees, you can use the following letter abbreviations \vskip 3pt \noindent \begin{tabular}{c>{\itshape}lr@{\hspace{.25cm}}c>{\itshape}lr} \em Letter & &\em degrees & \em Letter & &\em degrees\\ "U" & Up & 0 &"N" & North & *0\\ "L" & Left & 90&"W" & West & *90\\ "D" & Down & 180&"S" & South & *180\\ "R" & Right & 270&"E" & East & *270\\ \end{tabular} \vskip 3pt describes the reference point of , and this reference point is what is placed at \c{}. By default, it is the center of the box. This can be changed setting to one or two of the following \begin{quote} \begin{tabular}{rlcrl} \multicolumn{2}{l}{\em Horizontal} & & \multicolumn{2}{l}{\em Vertical}\\ "l" & Left & & "t" & Top\\ "r" & Right & &"b" & Bottom\\ & & &"B" & Baseline \end{tabular} \end{quote} The following diagram shows the reference point represented by the various combinations (the dotted line is the baseline): \begin{quote} \begin{pspicture}(-2.4,-.9)(2.4,1.9) \UsageFont \psframe(-2,-.5)(2,1.5) \psline[linestyle=dotted](-2,0)(2,0) \uput[u](0,1.5){t} \uput[d](0,-.5){b} \rput*(0,0){B} \uput[l](-2,.5){l} \uput[l](-2,0){Bl} \uput[dl](-2,-.5){bl} \uput[ul](-2,1.5){tl} \uput[r](2,.5){r} \uput[r](2,0){Br} \uput[dr](2,-.5){br} \uput[ur](2,1.5){tr} \end{pspicture} \end{quote} \begin{quote} \PSTCom \rput*`[refpoint]{rotation}'\cAny{stuff} \end{quote} It is important to realize that "\rput" resets the (0,0) point to the chosen coordinate, as shown in the following example: \begin{GridPSExample}(0,0)(2.2,2) \rput(.1,.1){\psline(0,0)(1.3,1.3)} \rput{-20}(1.2,.4){\psline(0,0)(1,0)} \end{GridPSExample} Note that rotation was applied last of all. Because it is very often a requirement to \emph{put} a label next to some object, a variant of "\rput" is provided: \PSTCom \uput*`{labsep}'[refangle]`{rotation}'\cAny{stuff} which places in the direction , at a distance of from \c{}. defaults to 5pt. As before, since angles are often in steps of 45\degrees, letter abbreviations are provided for common cases: \vskip3pt\noindent \begin{tabular}{@{}c>{\itshape}lr@{\hspace{.25cm}}c>{\itshape}lr@{}} {\em Letter} & &\em degrees& {\em Letter} & & \em degrees\\ "r" & right & 0 & "ur" & up-right & 45\\ "u" & up & 90 & "ul" & up-left & 135\\ "l" & left & 180 & "dl" & down-left & 225\\ "d" & down & 270&"dr" & down-right & 315\\ \end{tabular} \vskip3pt \begin{small} \begin{longtable}{>\small lP{.41\textwidth}} \caption{\protect\PST\ basic drawing commands\label{PSTbasic}}\\ \hline \endfirsthead \caption*{\protect\PST\ basic drawing commands \emph{cont.}}\\ \hline \endhead \PSTComOpt \parabola`{arrows}'\c0\c1 &Draw a parabola that starts at \c0, passes through \c0, and whose maximum or minimum is \c1 \\ \PSTComOpt \psarc`{arrows}\c~'{radius}{angleA}{angleB} &Draw a circle segment between \emph{angle1} and \emph{angle2} (counter-clockwise); \\ \PSTComOpt \psarcn`{arrows}\c~'{radius}{angleA}{angleB} &As \Usage{psarc}, but the arc is drawn \emph{clockwise} \\ \PSTComOpt \psbezier`{arrows}(\x0,\y0)'(\x1,\y1)(\x2,\y2)(\x3,\y3) &Draw a Bezier curve with four control points \\ \PSTComOpt \psccurve`{arrows}'\c1`\ldots\c n' &Draw a closed curve between the points \\ \PSTCom \pscharclip`*[settings]'{text} ... \Main \endpscharclip &Set the clipping path to the character shapes\\ \PSTCom \pscharpath`*[settings]'{text} &The \emph{text} obeys the \PST\ \textbf{linestyle} and \textbf{fillstyle} commands; this is only effective if the font used is a \PS\ Type1 font\\ \PSTComOpt \pscircle`(\x0,\y0)'{radius} & Draw a circle with the center at \c0 \\ \PSTComOpt \pscirclebox{text} &Draw a circle around the text \\ \PSTCom \pscoil`*[settings]{arrows}\c0'\c1 &Draw a 3D coil from \c0 to \c1 \\ \PSTCom \psCoil`*[settings]'{angle1}{angle2} &Draw a coil horizontally from \emph{angle1} to \emph{angle2}\\ \PSTComOpt \pscurve`{arrows}'(\x1,\y1)`\ldots(\x n,\y n)' &Draw an open curve through the points \\ \PSTComOpt \psdblframebox{text} &Draw a double box around the text \\ \PSTComOpt \psdiabox{text} &Draw a diamond around the text\\ \PSTCom \psdiamond`(\x0,\y0)'(\x1,\y1) &Draw diamond centred at \c0 with the half width \x1 and height \y1 \\ \PSTCom \psdots`*[settings]'(\x1,\y1)`(\x2,\y2)\ldots(\x n,\y n)' &Draw dot at each coordinate \\ \PSTComOpt \psecurve`{arrows}'(\x1,\y1)`\ldots(\x n, \y n)' &Draw an open curve, but omitting the last and first points \\ \PSTComOpt \psellipse`(\x0,\y0)'(\x1,\y1) &Draw an ellipse with centre at \c0, and horizontal and vertical radii of \x1 and \y1 \\ \PSTComOpt \psframe`(\x0,\y0)'(\x1,\y1) & Draw a rectangular frame with corners at \c0 and \c1\\ \PSTComOpt \psframebox{text} &Draw a box around the text \\ \PSTCom \psgrid`(\x0,\y0)(\x1,\y1)(\x2,\y2)' &Superimpose a grid with corners at \c1 and \c2, labelled on the axes starting from \c0 \\[6pt] \PSTComOpt \psline`{arrows}(\x0,\y0)'(\x1,\y1)`\ldots(\x n,\y n)' & Draw a line through a series of coordinates\\ \PSTComOpt \psovalbox{text} &Draw an oval around the text\\ \PSTComOpt \pspolygon`(\x0,\y0)'(\x1,\y1)(\x2,\y2)`\ldots(\x n,\y n)' & Draw a line through the coordinates, and then close the path to make an object that can be filled\\ \PSTComOpt \psshadowbox{text} &Draw a box around the text, with a shadow\\ \PSTCom \pstextpath`[pos]\cAny'{graphics object}{text} &The \emph{text} is drawn along the line defined by the \emph{graphics object}. \emph{pos} determines how the text relates to the path; by default (l), it starts at the beginning of the path; \texttt{c} will center the text along the path and \texttt{r} will make it finish at the end of the path. \c{} provides an offset for the text in relation to the path. By default it is offset above the line by .7ex. \emph{This macro, and} \verb|\pscharclip|, \emph{are not guaranteed to work with every dvi to \PS\ driver!}\\ \PSTCom \pstriangle`(\x0,\y0)'(\x1,\y1) &Draw isoceles triangle with base centred at \c0, width \x1, and height \y1 \\ \PSTComOpt \pstribox{text} &Draw a triangle around the text \\ \PSTComOpt \pswedge`(\x0,\y0)'{radius}{angle1}{angle2} &Draw a wedge segment between \emph{angle1} and \emph{angle2} (counter-clockwise) \\ \PSTCom \pszigzag`*[settings]{arrows}\c0'\c1 &Draw a zigzag from \c0 to \c1 \\ \hline \end{longtable} \end{small} \begin{table*} \begin{minipage}[b]{.5\textwidth}\centering \def\myline#1{\psline{#1}(0,1ex)(1.3,1ex)}% \catcode`\<=12 \begin{tabular}[b]{cll}% {\em Value} & \hbox to 1.3cm{\em Example\hss} & \\ \hline "-" & \myline{-} & None\\ "<->" & \myline{<->} & Arrowheads.\\ ">-<" & \myline{>-<} & Reverse arrowheads.\\ "<<->>" & \myline{<<->>} & Double arrowheads.\\ ">>-<<" & \myline{>>-<<} & Double reverse arrowheads.\\ "|-|" & \myline{|-|} & T-bars, flush to endpoints.\\ "|*-|*" & \myline{|*-|*} & T-bars, centered on endpoints.\\ "[-]" & \myline{[-]} & Square brackets.\\ "(-)" & \myline{(-)} & Rounded brackets.\\ "o-o" & \myline{o-o} & Circles, centered on endpoints.\\ "*-*" & \myline{*-*} & Disks, centered on endpoints.\\ "oo-oo" & \myline{oo-oo} & Circles, flush to endpoints.\\ "**-**" & \myline{**-**} & Disks, flush to endpoints.\\ "c-c" & \myline{c-c} & Extended, rounded ends.\\ "cc-cc" & \myline{cc-cc} & Flush round ends.\\ "C-C" & \myline{C-C} & Extended, square ends.\\ "|<->|" & \myline{|<->|} & T-bars and arrowheads.\\ "|<*->|*" & \myline{|<*->|*} & T-bars and arrowheads, flush.\\ \end{tabular} \caption{\protect\PST\ line terminators} \label{PSTarrows} \end{minipage}% \begin{minipage}[b]{.5\textwidth}\centering \def\mydots#1{% \psdots[dotstyle=#1](.1,1ex)(.55,1ex)(1,1ex)(1.45,1ex)(1.9,1ex)}% \begin{tabular}[b]{ll} \emph{Style}&\emph{Example\qquad\qquad}\\ \hline "*" & \mydots{*} \\ "o" & \mydots{o} \\ "+" & \mydots{+} \\ "x" & \mydots{x} \\ "|" & \mydots{|} \\ "asterisk" & \mydots{asterisk} \\ "oplus" & \mydots{oplus} \\ "otimes" & \mydots{otimes} \\ "triangle" & \mydots{triangle}\\ "triangle*" & \mydots{triangle*}\\ "square" & \mydots{square}\\ "square*" & \mydots{square*}\\ "diamond" & \mydots{diamond}\\ "diamond*" & \mydots{diamond*}\\ "pentagon" & \mydots{pentagon} \\ "pentagon*" & \mydots{pentagon*}\\ \mbox{}\\ \mbox{} \end{tabular}% \caption{\protect\PST\ dot styles} \label{dotstyles} \end{minipage} \end{table*} \section{Examples of basic graphic objects} The following examples demonstrate some of the \PST\ building blocks, and the use of the graphics parameters. We must remember that all these simple objects take up no space; the surrounding \texttt{pspicture} defines the space \TeX\ is to leave, but within that, we are drawing entirely by coordinates. \begin{GridPSExample}(0,0)(2,1) \psline(2,1) \end{GridPSExample} \begin{GridPSExample}(0,0)(2,1) \psline[linestyle=dashed](2,1) \end{GridPSExample} \begin{GridPSExample}(0,0)(2,1) \psline[linewidth=0.6mm,doubleline=true, doublesep=0.5mm]{->}(2,1) \end{GridPSExample} \begin{GridPSExample}(0,0)(4,2) \psline[linearc=0.25,showpoints=true]{->}% (1,0)(4,0.3)(2,2)(0,0.5) \psline[linestyle=dotted,linecolor=blue, arrowlength=3]{<->}(0,1)(3,0)(4,2) \end{GridPSExample} \begin{GridPSExample}(0,0)(4,2) \psframe[fillstyle=solid,fillcolor=pink] (1,0)(4,1) \psframe[fillstyle=solid,fillcolor=white, framearc=0.5](3,0.2)(3.8,0.8) \pspolygon[linewidth=0.7mm,dimen=inner] (0,1)(2,2)(3,1)(2,0) \end{GridPSExample} \begin{GridPSExample}(0,0)(4,2) \psdiamond(1.5,1.5)(1.5,0.5) \pstriangle[fillstyle=solid, fillcolor=yellow](2,0)(3,1) \end{GridPSExample} \begin{GridPSExample}(0,0)(3,2) \pscircle[linewidth=1mm,linecolor=green] (1,1){1} \pscircle[linestyle=none,fillstyle=solid, fillcolor=lightblue](1,1){0.5} \pscircle[fillstyle=crosshatch](2.5,1.5) {0.5} \end{GridPSExample} \begin{GridPSExample}(0,0)(4,2) \psellipse[linecolor=green, fillstyle=vlines,hatchangle=0, hatchcolor=red](1,1)(1,0.5) \pswedge[fillstyle=solid, fillcolor=lightgray] (2.5,1){1}{0}{120} \end{GridPSExample} \begin{GridPSExample}(0,0)(3,2) \psdots[linecolor=blue,dotstyle=triangle, dotscale=2](0,0.5)(1,2)(2.8,1.5) \pscurve[linecolor=cyan,showpoints=true] {->}% (0,1.2)(1.3,1.8)(3,0.4)(0.5,0.2) \psarc(2,1.5){1}{180}{320} \parabola[linecolor=red]{<->}% (0.3,0.3)(1.5,1.5) \end{GridPSExample} \begin{GridPSExample}(0,0)(4,2) \psbezier[linewidth=0.8mm,linecolor=red, showpoints=true]{|->}% (1,0)(4,1)(2,2)(0,0) \end{GridPSExample} \section{Mixing text and graphics} When we come to consider text, the situation is rather different; now the size of objects is determined by the size of the enclosed text. Here \TeX\ \emph{is} aware of the space used, so successive objects are placed as if they were letters, and coordinates are not used. \begin{example**} \psframebox{The Buck Stops Here} \end{example**} \begin{example**} \psframebox[fillstyle=solid, fillcolor=black] {\bfseries\color{white}\LARGE Beware of The Dog} \end{example**} \begin{example**} \psframebox{The dragon} \psframebox {\psframebox[linecolor=green]{ate} \psframebox[linecolor=blue] {\psframebox[linecolor=red]{the women} and \psframebox[linecolor=red]{children}}} \end{example**} \begin{example**} \psshadowbox[fillstyle=solid, fillcolor=yellow] {\color{red}\begin{tabular}{c} Chapter 1\\We go to sea \end{tabular}} \end{example**} \begin{example**} \pscirclebox[doubleline=true] {\bfseries STOP!} \end{example**} \begin{example**} \psdblframebox[linecolor=green] {\color{red}All Hail Caesar!} \end{example**} \begin{example**} \psdiabox{\sffamily No Parking} \end{example**} \begin{example**} \pstribox[shadow=true,fillstyle=gradient, gradbegin=green,gradend=red] {\color{white}\Large$\Omega$ } \end{example**} \begin{example**} \psovalbox[linecolor=red] {\color{blue}Today's Menu} \end{example**} \PS\ aficionados will be aware that text in \PS\ is treated just like any other graphical object (this was one of the great revolutions introduced by the language), and can be manipulated. The following examples demonstrate the \Lcs{pstextpath} macro, which has two parameters: a graphic object, and some text. The text is made to fit the graphical object; only simple text is allowed, but that includes maths. \begin{PSExample}(-4,-3)(3,0) \psset{linecolor=lightgray} \pstextpath {\pscurve(-4,-2)(-2,0)(0,-3)(2,-1)(3,-3)} {\color{blue} If you want to type $2=\int_0^\pi \sin\theta\, \mathrm{d}\theta$ and let it follow along a curving line \ldots} \end{PSExample} It is also possible to set text as if it were a graphic, with the fill, colour and line properties. This is done with the \Lcs{pstextpath} macro; it has limitations (for instance, it cannot be mixed with \Lcs{pstextpath}), but it is still a useful tool for special occasions: \begingroup\fontfamily{ptm} \begin{GridPSExample}(0,-.2)(2.5,1.8) \pscharpath[fillstyle=solid, fillcolor=lightblue, linewidth=.4pt] {\fontsize{72}{72}\selectfont \LaTeX} \end{GridPSExample} \endgroup Admirers of the distinctive style of Dorling Kindersley publications may like to try the following effect: \begin{example**} \begin{pspicture}(-4,-3)(4,1) \psset{fillstyle=solid,shadow=true,shadowangle=0} \DeclareFixedFont{\babyfont}{T1}{ptm}{m}{n}{2cm} \DeclareFixedFont{\wordfont}{T1}{ptm}{m}{n}{1.5cm} \def\Cc#1#2{\pscharpath[fillcolor=#1]{#2}} \bfseries \rput(0,0){\babyfont \Cc{red}B\Cc{green}A\Cc{yellow}B% \Cc{red}{Y'}\Cc{blue}S} \rput(0,-2){{\wordfont\Cc{blue}{WORLD}}} \end{pspicture} \end{example**} The third of these tools which treat text like a graphic is \Lcs{pscharclip}; this takes a parameter of some text, and its effect is terminated by \Lcs{endpscharclip}. Any objects drawn inside this group are clipped to the shape of the letters. %%% Bounding box corrected by hand to %%%%%BoundingBox: 145 635 380 667 %%% dvips -E came up with which leaves far too much space %%%%%BoundingBox: 119 351 380 667 \begin{Example**} \newcounter{myN} \DeclareFixedFont{\bigsf}{T1}{phv}{b}{n}{1.3cm} \DeclareFixedFont{\tinyrm}{T1}{ptm}{m}{n}{2mm} \setcounter{myN}{110} \begin{pspicture}(0,0)(8.2,1) \pscharclip[linecolor=yellow,fillstyle=solid, fillcolor=red] {\rput[bl](0,0){\bigsf CHOCOLATE}} \rput[t]{90}(0,0) {\vbox {\hsize=2cm \offinterlineskip \tinyrm\color{black} \loop \addtocounter{myN}{-1} \ifnum\value{myN}>0 nuts and raisins \repeat}} \endpscharclip \end{pspicture} \end{Example**} \section{Working with a third dimension} Later versions of \PST\ offer some experimental facilities for viewing objects in three dimensions. Two-dimensional objects can be projected in a 3D coordinate system, and arbitrary viewpoints established. At the present time, \PST\ does not support true 3D solid objects, perspective projection, hidden-line removal, or lighting of objects, so the usefulness of this part of the package is limited. However, with some patience, pleasing effects can be obtained (well demonstrated, as usual, by \cite{Girou:1994}). Table~\ref{PST3d} lists the new commands, and Table~\ref{PSTparms3d} describes the extra graphics parameters which apply to them. \begin{table*} \begin{tabular}{lP{.5\textwidth}} \hline \PSTComOpt \psshadow{text} &Draw a shadow on the text\\ \PSTComOpt \pstilt{degrees}{text} &Place \texttt{text} tilted\\ \PSTCom \ThreeDPut`(\x0,\y0,\z0)'{object} &Place \emph{object} at coordinate \x0,\y0,\z0, displayed according to the current viewpoint\\ \hline \end{tabular} \caption{\protect\PST\ 3D commands}\label{PST3d} \end{table*} \begin{table*} \begin{tabular}{llP{.5\textwidth}} \emph{Parameter} & \emph{Default} & \emph{Explanation}\\ \hline \Par{Tshadowsize=size} (1)&Length of shadow\\ \Par{Tshadowcolor=colour} (lightgray)&Colour of shadow\\ \Par{Tshadowangle=angle} (60)&Angle of shadow\\ \Par{viewpoint=x y z} (1 -1 1) &position of the observer looking at the object origin \\ \Par{normal=x y z} (0 0 1) & A vector orthogonal to the plane of the 2D object, which specifies its position in 3D space\\ \Par{embedangle=angle} (0) & The rotation around the axis through the reference point of the object in the direction of the positioning vector\\ \hline \end{tabular} \caption{\protect\PST\ 3D graphical parameters}\label{PSTparms3d} \end{table*} There are two high-level `3D' commands, and one general tool. The high-level commands are \Lcs{psshadow}, which attaches a shadow to some text, and \Lcs{pstilt}, which angles an object into the third dimension. \begin{example**} \psshadow[Tshadowangle=45, Tshadowsize=2.5]{% \LARGE\bfseries Words with a shadow} \end{example**} \begin{PSExample}(0,-3)(3,1.5) \rput(0,1){\pstilt{45}{I Feel Ill!}} \rput(0,0){\pstilt{-75}{\psgrid(2,2)}} \end{PSExample} \begin{figure*}[!t]\centering \def\CurrentPackages{pstcol} \begin{Escape} \makeatletter \def\DieFrame{\@ifnextchar[{\DDieFrame}{\DDieFrame[darkgray]}} \def\DDieFrame[#1]{\psframe[linecolor=black,fillcolor=#1,fillstyle=solid](4,4)} \makeatother \def\SpotColor{white} \def\DieOne{\DieFrame[lightgray] \pscircle*[linecolor=\SpotColor](2,2){.3} } \def\DieTwo{\DieFrame[lightgray] \pscircle*[linecolor=\SpotColor](1,2){.3} \pscircle*[linecolor=\SpotColor](3,2){.3} } \def\DieThree{\DieFrame[lightgray] \pscircle*[linecolor=\SpotColor](1,1){.3} \pscircle*[linecolor=\SpotColor](2,2){.3} \pscircle*[linecolor=\SpotColor](3,3){.3} } \def\DieFour{\DieFrame \pscircle*[linecolor=\SpotColor](1,1){.3} \pscircle*[linecolor=\SpotColor](3,3){.3} \pscircle*[linecolor=\SpotColor](1,3){.3} \pscircle*[linecolor=\SpotColor](3,1){.3} } \def\DieFive{\DieFrame \pscircle*[linecolor=\SpotColor](1,1){.3} \pscircle*[linecolor=\SpotColor](3,3){.3} \pscircle*[linecolor=\SpotColor](1,3){.3} \pscircle*[linecolor=\SpotColor](3,1){.3} \pscircle*[linecolor=\SpotColor](2,2){.3} } \def\DieSix{\DieFrame \pscircle*[linecolor=\SpotColor](1,1){.3} \pscircle*[linecolor=\SpotColor](1,2){.3} \pscircle*[linecolor=\SpotColor](1,3){.3} \pscircle*[linecolor=\SpotColor](3,1){.3} \pscircle*[linecolor=\SpotColor](3,2){.3} \pscircle*[linecolor=\SpotColor](3,3){.3} } \def\DieSide#1#2#3{\ThreeDput[normal=#1](#2){#3}} \def\TheDie#1#2(#3)(#4){% \begin{pspicture}(#3)(#4) \ifcase #1 \relax \or %1 \psset{viewpoint=-1 -1 #2} \DieSide{-1 0 0}{0,4,0}{\DieThree} \DieSide{0 -1 0}{0,0,0}{\DieFive} \or %2 \psset{viewpoint=1 -1 #2} \DieSide{0 -1 0}{0,0,0}{\DieFive} \DieSide{1 0 0}{4,0,0}{\DieFour} \or %3 \psset{viewpoint=1 1 #2} \DieSide{1 0 0}{4,0,0}{\DieFour} \DieSide{0 1 0}{4,4,0}{\DieTwo} \or %4 \psset{viewpoint=-1 1 #2} \DieSide{0 1 0}{4,4,0}{\DieTwo} \DieSide{-1 0 0}{0,4,0}{\DieThree} \fi \ifnum#2<0 \DieSide{0 0 -1}{0,4,0}{\DieSix} \else \DieSide{0 0 1}{0,0,4}{\DieOne} \fi \end{pspicture}} \psset{unit=.35cm} \framebox{% \begin{tabular}{cccc} \TheDie{1}{1}(-5,-2.5)(5,7.5)& \TheDie{2}{1}(-2.5,-3.5)(7.5,6.5)& \TheDie{3}{1}(-5,-5)(5,5)& \TheDie{4}{1}(-7.5,-4)(2.5,6)\\ \TheDie{1}{-1}(-5,-5)(5,5)& \TheDie{2}{-1}(-2.5,-3.5)(7.5,6.5)& \TheDie{3}{-1}(-5,-2.5)(5,7.5)& \TheDie{4}{-1}(-7.5,-4)(2.5,6) \end{tabular} } \end{Escape} \caption{Different views of a dice cube}\label{PSTdice} \end{figure*} The general macro is \Lcs{ThreeDPut}, which places any \PST\ object at a point in 3D space. This will almost always set the \texttt{normal} graphics parameter, which sets the vector which will be orthogonal to the plane of the object. To take a simple example, suppose we want to draw a house, with a reference origin at the left-hand end of the front wall; the left side wall would be drawn as follows: \begin{PSExample}(-3.5,-1.2)(4,2.5) \psset{unit=.5cm} \psset{viewpoint=-1 -1 1} \ThreeDput[normal=0 0 1]{\psgrid(-3,-3)(6,6)} \ThreeDput[normal=-1 0 0](0,4,0){ \psframe*[linecolor=yellow](4,4)} \end{PSExample} The viewpoint is from `up, back and to the left'. When we draw a whole cube, it is important to realize that \PST\ does not check which side hides which; the last side drawn will wipe out others drawn earlier, regardless of the fact that it is `behind' them in 3D space. When drawing the different views, we have to give the sides in different orders. Fig.~\ref{PSTdice} shows this problem, since when we show the `underneath' well, we have to be sure to draw all the six faces in the right order for the viewpoint. The attempt to provide `lighting' on the die is done simply by colouring three faces in a lighter colour. To attempt formal ray-tracing from a light source would be considerably beyond the scope of this package! Following another example by Denis Girou, we can use the \Lcs{ThreeDPut} macro to generate the appearance of raised text: % this one uses too much memory redefining colours %%% Bounding box corrected by hand to %%%%%%BoundingBox: 146 522 322 658 \begin{Example*} \begin{pspicture}(-3,0)(3,5.5) \psset{unit=.5cm} \font\bigfont=phvb8t at .8cm \psset{viewpoint=-1 -1 1.5,normal=0 0 1} \rput(0,0){\multido{\n=0+0.07}{12} {\definecolor{AColor}{rgb}{1, \n, \n} \ThreeDput(\n,\n,0){\pscircle[% linestyle=none,fillstyle=solid, fillcolor=AColor](5,5){6}}}} \psset{linestyle=none} \rput(0,0){\multido{\n=0+0.07}{12} {\definecolor{AColor}{rgb}{1, \n, \n} \ThreeDput(\n,\n,0){\bigfont \pstextpath[c]{% \psarcn(5.5,5.5){4}{180}{0}}{% \color{AColor}Happy Christmas} \pstextpath[c]{% \psarc(5.5,5.5){4}{180}{0}}{% \color{AColor}\TeX\ Lovers}}}} \end{pspicture} \end{Example*} \DeleteShortVerb{\"} \begin{thebibliography}{99} \bibitem[\protect\citename{Girou }1994]{Girou:1994} {Girou, D.} 1994. \newblock {Pr\'esentation de PSTricks}. {\em Cahiers GUTenberg}, {\bfseries 16}, 21--70. \bibitem[\protect\citename{{van Zandt} }1993]{Zandt:1993a} {{van Zandt}, T.} 1993. \newblock PSTricks User's Guide. \newblock Unpublished documentation with the software, version 0.93a. \bibitem[\protect\citename{{van Zandt} \& Girou }1994]{Zandt-Girou:1994} {{van Zandt}, T. \& Girou, D} 1994. \newblock Inside PSTricks. {\em TUGboat}, {\bfseries 15 (3)} September, 239--246. \end{thebibliography} \end{Article}