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diff --git a/systems/doc/pdftex/manual/pdftex.tex b/systems/doc/pdftex/manual/pdftex.tex new file mode 100644 index 0000000000..2ca532568b --- /dev/null +++ b/systems/doc/pdftex/manual/pdftex.tex @@ -0,0 +1,4354 @@ +% pdfTeX manual, rewritten in LaTeX from the ConTeXt original, +% Karl Berry, 2023. Content not significantly changed. +% Released under the GFDL v1.2+, same as the ConTeXt version. +% +% Not quite tagging-ready, numerous warnings like: +% Package tagpdf Warning: The structure Sect can not be closed. +% and ends with: +% ./pdftex.tex:4336: Package tagpdf Error: The number of automatic begin +% (1351) and end (1352) ... +% +%\DocumentMetadata{testphase={phase-III,table}} +\documentclass{pdftexmanual} +\svnscan $Id: pdftex.tex 921 2024-02-02 02:14:32Z karl $ + +% +\title{The pdf\TeX\ user manual} +\author{\THANH\ and others} +\date{\PDFTEX\ \currentpdftex\\ + \hspace*{1em}\\ \today\\ + \hspace*{1em}\\ \url{https://pdftex.org} + } + +\begin{document} +\hypersetup{pageanchor=false} % avoid hyperref duplicate page.1 warning +\maketitle +\hypersetup{pageanchor=true} % https://tex.stackexchange.com/questions/18924 +\setcounter{page}{2} + +\tableofcontents + +\chapter{Introduction} + +The main purpose of the \PDFTEX\ project is to create and maintain an +extension of \TEX\ that can produce \PDF\ output directly from \TEX\ +source files and improve\slash enhance the result of \TEX\ typesetting +with the help of \PDF\ output. When \PDF\ output is not selected, +\PDFTEX\ produces standard \DVI\ output. An important aspect of the +project is to investigate alternative justification algorithms; notably, +the margin kerning and font expansion algorithms following the \HZ\ +micro\hyph typography algorithm by Prof.~Hermann Zapf. + +\PDFTEX\ is maintained by \THANH, the original author, and others. The +\PDFTEX\ home page is \useurl{ptexorg}. Please send bug reports, +suggestions, etc., to the mailing list (\useurl{ptexbugs}). + +\PDFTEX\ is based on the original \TEX\ sources and \WEBC, and has been +successfully compiled on \UNIX, \WIN\ and many other systems. It is +actively maintained, with great care taken to keep new \PDFTEX\ versions +backward\hyph compatible with earlier ones. + +A conservative successor to \TEX, named \ETEX, was developed in the +1990s. Since \PDFTEX\ version 1.40, the \ETEX\ extensions are compiled +as part of the \PDFTEX\ engine and thus always available. For +documentation on the \ETEX\ extensions, see \useurl{etexctan}. + +Furthermore, \PDFTEX\ itself has acquired plenty of extensions over the +years which are not related specifically to \PDF\ output, generally new +primitives for various features that are inconvenient or impossible to +implement at the \TEX\ level. Many of these extensions have been adopted +across all engines (sometimes with different primitive names or variant +functionality), and some are required by \LATEX. Therefore, in most +distributions \type{etex} is a link to \type{pdftex}; the difference +being whether \DVI\ or \PDF\ output is generated by default. + +Other extensions are \MLTEX\ and \ENCTEX; these are also included in the +\PDFTEX\ implementation, although they are rarely used for new documents. + +\PDFTEX\ does not natively support \UTFEIGHT\ input text, +Unicode-encoded fonts, or anything else related to Unicode, as it was +written long before Unicode became widespread. Making those changes to +the engine now would necessarily create unacceptable incompatibilities, +so there are no plans to do so. Thus, when using \PDFTEX, \LaTeX\ and +other formats handle \UTFEIGHT\ (and other) input at the \TEX\ macro +level, which works well enough in practice for most documents. It is +also possible to use TrueType and OpenType fonts with \PDFTEX, if you +choose an 8-bit subset to be encoded. + +If you need a \TeX\ engine with native support for Unicode input, +TrueType fonts, OpenType fonts, please look into \LUATEX\ +(\useurl{luatex}) or \XETEX\ (\useurl{xetex}). + +\section{About this manual} + +This manual revision (\rcsrevision) covers \PDFTEX\ development up to +version \currentpdftex. The primary repository for both the manual and +the \PDFTEX\ sources is \useurl{ptexdevel}. The typeset manual in \PDF\ +format can be found on \CTAN\ in \useurl{ptexctan}. + +Thanks to the many people who have contributed to the manual. +Improvements are always possible, and bugs not unlikely. +Please send questions or suggestions via email at \useurl{ptexbugs}. + +\section{Legal notice} + +Copyright \copyright\ 1996--2024 \THANH. +Permission is granted to copy, distribute and/or modify this document +under the terms of the GNU Free Documentation License, Version 1.2 +or any later version published by the Free Software Foundation; +with no Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts. +A copy of the license is included in the section entitled ``GNU +Free Documentation License''. + +\section{About \PDF} + +Let's start with a very brief introduction to \PDF\ format. For our +example, the bit of \TeX\ source below (figure~\ref{fig.titlesource}) +generates the nearly-minimal \PDF\ file shown on the next page +(figure~\ref{fig.titleout}). Since compression is disabled, such a +\PDF\ file is rather verbose and readable. The first line +(\texttt{\%PDF-1.4}) specifies the \PDF\ version used. \PDF\ viewers are +supposed to silently skip over all elements they cannot handle. + +\begin{figure}[b] +\bigskip +\hrule +\medskip +\begin{verbatim} + \pdfoutput=1 + \pdfcompresslevel=0 + \pdfobjcompresslevel=0 + \pdfmapline{ptmr8r Times-Roman 2 <8r.enc} + \font\tenrm=ptmr8r + \tenrm + Welcome to pdf\TeX! + \end +\end{verbatim} +\vspace{-\baselineskip} +\caption{This plain \TeX\ source generates \PDF\ output shown in + figure~\ref{fig.titleout}.} +\label{fig.titlesource} +\end{figure} + +\begin{figure}[p] +% Why isn't \vsize enough? +\includegraphics[height=1.27\vsize,alt={small PDF file}] + {incl/pdfmin-crop.pdf} +\caption{The \PDF\ output for the \TeX\ source in figure~\ref{fig.titlesource}.} +\label{fig.titleout} +\end{figure} + +A \PDF\ file consists of objects. These objects can be recognized by their +number and keywords. For example, over in the second column, we can see +(modulo editorial line breaks): + +\begin{verbatim} +9 0 obj << /Type /Catalog /Pages 5 0 R >> endobj +\end{verbatim} + +Here \verb|9 0 obj ... endobj| is the object capsule. The first number +is the object number (no.~9). The sequence \verb|5 0 R| is an object +reference, that is, a pointer to another object (no.~5). The second +number (here a zero) is currently not used in \PDFTEX; it is the version +number of the object. It is, for instance, used by \PDF\ editors, when +they replace objects by new ones. + +When a viewer opens a \PDF\ file, it goes to the end of the file, +looking for the keyword \type{startxref}. The number after +\type{startxref} gives the absolute position (byte offset from the file +start) of the so\hyph called ``object cross-reference table'' that +begins with the keyword \type{xref}. This table in turn tells the byte +offsets of all objects that make up the \PDF\ file, providing fast +random access to the individual objects (here the \type{xref} table +shows 11~objects, numbered from~0 to~10; object no.~0 is always unused). +The actual starting point of the file's object structure is defined +after the \type{trailer}: the \type{/Root} entry points to the +\type{/Catalog} object (no.~9). In this object the viewer can find the +pointer \type{/Pages} to the page list object (no.~5). In our example we +have only one page. The trailer also usually holds an \type{/Info} +entry, which points to an object (no.~10) with a bit more about the +document. We can follow the thread: + +\begin{quote} +\type{/Root} $\longrightarrow$ object~9 $\longrightarrow$ +\type{/Pages} $\longrightarrow$ object~5 $\longrightarrow$ +\type{/Kids} $\longrightarrow$ object~2 $\longrightarrow$ +\type{/Contents} $\longrightarrow$ object~3 +\end{quote} + +As soon as we add annotations, a fancy word for hyperlinks and the like, +some more entries will be present in the catalog. We invite users to +take a look at the \PDF\ code of this file to get an impression of that. + +The page content is a stream of drawing operations. Such a stream can be +compressed, where the level of compression can be set with +\cs{pdfcompresslevel} (compression is switched off for the title page). +Let's take a closer look at this stream in object~3. Often (but not in +our example) there is a transformation matrix, six numbers followed by +\type{cm}. As in \POSTSCRIPT, the operator comes after the operands. +Between \type{BT} and \type{ET} comes the text. A font is selected by a +\type{Tf} operator, which is given a font resource name \type{/F..} and +the font size. The actual text goes into parentheses \type{()} so that +it creates a \POSTSCRIPT\ string. The numbers in bracket pairs provide +horizontal movements like spaces and fine glyph positioning (kerning). +When one analyzes a file produced by a less sophisticated typesetting +engine, whole sequences of words can be recognized. In \PDF\ files +generated by \PDFTEX\ however, many words come out rather fragmented, +mainly because a lot of kerning takes place; in our example the +\type{80} moves the text \type{(elcome)} left towards the letter +\type{(W)} by 80/1000 of the font size. \PDF\ viewers in search mode +simply ignore the kerning information in these text streams. When a +document is searched, the search engine reconstructs the text from these +(string) snippets. + +Every \type{/Page} object points also to a \type{/Resources} object +(no.~1) that gives all ingredients needed to assemble the page. In our +example only a \type{/Font} object (no.~4) is referenced, which in turn +tells that the text is typeset in \type{/Font} \type{/Times-Roman}. The +\type{/Font} object points also to a \type{/Widths} array (object no.~7) +that tells for each character by how much the viewer must move forward +horizontally after typesetting a glyph. + +More details about the font can be found in the \type{/FontDescriptor} +object (no.~8); if a font file is embedded, this object points to the +font program stream. But as the Times-Roman font used for our example is +one of the 14 so\hyph called standard fonts that should always be present in +any \PDF\ viewer and therefore need not be embedded in the \PDF\ file, +it is left out here for brevity. However, when we use for instance a +Computer Modern Roman font, we have to make sure that this font is later +available to the \PDF\ viewer, and the best way to do this is to embed +the font. It's highly recommended nowadays to embed even the standard +fonts; you can't know how it looks exactly at the viewer side unless you +embed every font. + +In this simple file we don't specify in what way the file should be +opened, for instance full screen or clipped. A closer look at the page +object no.~2 (\type{/Type/Page}) shows that a mediabox +(\type{/MediaBox}) is part of the page description. A mediabox acts like +the (high-resolution) bounding box in a \POSTSCRIPT\ file. \PDFTEX\ +users can add dictionary entries to page objects with the +\cs{pdfpageattr} primitive. + +Although in most cases macro packages will shield users from these +internals, \PDFTEX\ provides access to many of the entries described +here, either automatically by translating the \TEX\ data structures into +\PDF\ ones, or manually by pushing entries to the catalog, page, info or +self-created objects. One can for instance create an object by using +\cs{pdfobj}, after which \cs{pdflastobj} returns its number. So + +\begin{verbatim} +\pdfobj { << /Type/ExtGState /LW 2 >> } +\end{verbatim} + +\noindent inserts an object into the \PDF\ file (it creates a ``graphics +state'' object setting the line width to 2~units), and \cs{pdflastobj} +now returns the number \PDFTEX\ assigned to this object. Unless objects +are referenced by others, they will just end up as isolated entities, +not doing any real harm but bloating the \PDF\ file. + +In general this rather direct way of pushing objects in the \PDF\ files +by primitives like \cs{pdfobj} is not very useful, and only makes +sense when implementing, say, fill\hyph in field support or annotation +content reuse. We will come to that later. + +Of course, this is just the barest introduction to \PDF\ format. For +those who want to learn more about technical \PDF\ details, the best bet +is to read the \PDFReference\ (\useurl{pdfreference}). + +We turn now to the specifics of \PDFTEX. + +\chapter{Invoking \PDFTEX} + +\PDFTEX\ has many command line options and can use many environment +variables and configuration file settings. Except for the simple and +rarely-used \type{-draftmode} and \type{-output-format} options, they +are all inherited from the common framework for \TeX\ engines as +implemented in \WEBC\ and Kpathsea. Their documentation is available at +\useurl{webc} and \useurl{kpathsea}. + +Two additional environment variables need more description here: first, +\type{SOURCE_DATE_EPOCH} (introduced in version 1.40.17, 2016). If this +is set, it must be a positive integer (with one trivial exception: if it +is set but empty, that is equivalent to 0). Non-integer values cause a +fatal error. The value is used as the current time in seconds since the +usual Unix ``epoch'': the beginning of 1970-01-01, UTC. Thus, a value of +\type{32} would result in a \type{/CreationDate} and \type{/ModDate} +values of \type{19700101000032Z}. This is useful for reproducible builds +of documents. (See also \cs{pdfinfoomitdate}, \cs{pdfsuppressptexinfo}, +et al.) + +The second, related, environment variable is \type{FORCE_SOURCE_DATE}. +If this is set to~\type{1}, \TEX's time-related primitives are also +initialized from the value of \type{SOURCE_DATE_EPOCH}. These primitives +are \cs{year}, \cs{month}, \cs{day}, and \cs{time}. If +\type{SOURCE_DATE_EPOCH} is not set, setting \type{FORCE_SOURCE_DATE} +has no effect. If \type{FORCE_SOURCE_DATE} is unset, set to the empty +string, or set to~\type{0}, the primitives reflect the current time as +usual. Any other value elicits a warning, and the current time is used. +This is useful if one wants to make reproducible \PDF{}s for a set +of documents without changing them in any way, \eg\ an operating system +distribution with manuals that use \cs{today}. Except in such unusual +circumstances, it is better not to set this, and let the \TEX\ +primitives retain the meaning they have always had. + +In addition, if both \type{SOURCE_DATE_EPOCH} and +\type{FORCE_SOURCE_DATE} are set, \cs{pdffilemoddate} returns a value +in UTC, ending in \type{Z}. (The values of the environment variables are +irrelevant in this case.) + +Finally, just to have the list of options and basic invocation at hand, +here is a verbatim listing of the \type{--help} and \type{--version} +output. All options can be specified with one or two dashes and +unambiguously abbreviated. + +\myverbatiminput{incl/pdftex-help.txt} + +\section{Macro packages supporting \PDFTEX} + +Currently all mainstream macro packages offer \PDFTEX\ support, with +automatic detection of \PDFTEX\ as engine. So there is normally no need +to turn on \PDFTEX\ support explicitly. + +\begin{itemize} +\item For \LATEX\ users, the \type {hyperref} package (originally + written by Sebastian Rahtz and Heiko Oberdiek; now maintained by + the \LaTeX\ team, has substantial support for \PDFTEX\ and + provides access to most of its features. In the simplest and most + common case, the user merely needs to load \type{hyperref}, and + all cross\hyph references will be converted to \PDF\ hypertext + links. \PDF\ output is automatically selected, compression is + turned on, and the \PDF\ page size is set up correctly. Bookmarks + are created to match the table of contents. + +\item The standard \LATEX\ packages \type{graphics}, \type{graphicx}, and + \type{color} also have built-in \PDFTEX\ support, which allows + use of color, text rotation, and graphics inclusion commands. + +\item The \CONTEXT\ MkII system by Hans Hagen has full support + for \PDFTEX\ in its generalized hypertext features. + The latest \CONTEXT\ supports advanced \PDF\ output, but + uses a engine (\LMTX). + +\item \PDF\ from \GNU\ \TEXINFO\ documents can be created by running + \PDFTEX\ on the \TEXINFO\ file, instead of \TEX. Alternatively, + run the shell command \type{texi2pdf} instead of \type{texi2dvi}. + +\item For plain \TEX\ users, the \filename{miniltx.tex} file from the + \type{graphics-pln} package allows loading \type{graphics}, + \type{graphicx}, and \type{color}. \EPLAIN\ provides additional + support for hyperlinks. + +\item A modification of \filename {webmac.tex}, named \filename + {pdfwebmac.tex}, allows production of hyperlinked \PDF\ versions + of the literate source code written in \WEB, such as \PDFTEX. + +\end{itemize} + +For \TeX\ developers: as \PDFTEX\ generates the final \PDF\ output +without help of a postprocessor, macro packages that take care of these +\PDF\ features have to be set up properly. Tasks include handling color, +graphics, hyperlink support, threading, fonts, page imposition and +manipulation. All of these \PDF\hyph specific tasks can be controlled by +\PDFTEX's own primitives (a few also by a \PDFTEX\hyph specific +\verb|\special{pdf: ...}|). Any other \cs{special} commands, like the +ones defined for various \DVI\ postprocessors, are simply ignored by +\PDFTEX\ when in \PDF\ output mode; a warning is given for non\hyph +empty \cs{special} commands. + +When a macro package written for classical \TEX\ with \DVI\ output is to +be modified for use with \PDFTEX, it is helpful to get some insight to +what extent \PDFTEX\hyph specific support is needed. This info can be +gathered, for instance, by outputting the various \cs{special} commands +via \cs{message}. as in: + +\begin{verbatim} +\pdfoutput=1 \let\special\message +\end{verbatim} + +or, if this leads to confusion, + +\begin{verbatim} +\pdfoutput=1 \def\special#1{\write16{special: #1}} +\end{verbatim} + +and see what happens. As soon as one \type{special:} message turns up, +one knows for sure that some kind of \PDFTEX\hyph specific support is +needed, and often the message itself gives a indication of what is +needed. + +\chapter{Setting up fonts} + +\PDFTEX\ can work with Type~1 and TrueType fonts (and to a small extent +also with OpenType fonts). Font files should be available and embedded +for all fonts used in the generated \PDF. It is possible to use +\METAFONT\hyph generated fonts in \PDFTEX---but it is strongly +recommended not to use these fonts if an equivalent is available in +Type~1 or TrueType format, if only because bitmap Type~3 fonts render +poorly under enlargement. + +\section{Map files} +\label{sec.mapfile} + +Font map files provide the connection between \TEX\ \TFM\ font files +and outline font file names. They contain also information about +re\hyph encoding arrays, partial font embedding (``subsetting''), and +character transformation parameters (like SlantFont and ExtendFont). Those +map files were first created for \DVI\ postprocessors. But, as \PDFTEX\ +in \PDF\ output mode includes all \PDF\ processing steps, it also needs +to know about font mapping, and therefore reads in one or more map files. +Map files are not read in when \PDFTEX\ is in \DVI\ mode. Bitmap fonts +can (and normally should) be used without being listed in the map file. + +By default, \PDFTEX\ reads the map file \filename{pdftex.map}. In \WEBC, +map files are searched for using the \type{TEXFONTMAPS} config file value +and environment variable. By default, the current directory and various +system directories are searched. + +Within the map file, each font is listed on a single line. The syntax of +each line is upward\hyph compatible with \type{dvips} map files and can contain +the following fields (some are optional; explanations follow): + +\begin{quote} +\varname{tfmname psname fontflags special encodingfile fontfile} +\end{quote} + +Here are two (real-world) examples. All the values are explained in +detail in the following. + +{\small \begin{verbatim} +cmr10 CMR10 <cmr10.pfb +ptmr8y NimbusRomNo9L-Regu " TeXnANSIEncoding ReEncodeFont " <texnansi.enc <utmr8a.pfb +\end{verbatim} +\par % needed for tagging; alternative: \begin{small}...\end{small} + % another alternative: \AddToHookNext{env/verbatim/begin}{\small} +} + +It is mandatory that \varname{tfmname} is the first field. If a +\varname{psname} is given, it must be the second field. Similarly if +\varname{fontflags} is given it must be the third field (if +\varname{psname} is present) or the second field (if \varname{psname} is +left out). The positions of \varname{special}, \varname{encodingfile}, +and \varname{fontfile} can be mixed. + +\subsection{Map lines: \varname{tfmname}} +\label{sec.map-tfmname} + +The \varname{tfmname} field specifies the name of the \TFM\ file for a +font---the file name given in a \TEX\ \cs{font} command. This name must +always be given, with no extension. Examples: \type{cmr10}, +\type{ptmr8y}. + +\subsection{Map lines: \varname{psname}} + +The \varname{psname} field specifies the \POSTSCRIPT\ (or other outline) +font name, as defined within the outline font file. Examples: +\type{CMR10}, \type{NimbusRomNo9L-Regu}. It is highly recommended to use +the \varname{psname} field, but strictly speaking it is optional. It has +two main uses. + +First, when a \PDF\ file is embedded by \cs{pdfximage}, the +\type{/BaseFont} names in the font dictionaries of Type~1 and Type~1C +(CFF) fonts from the embedded \PDF\ file are checked against this {\em +psname} field. If names match, the glyphs of that font will not be +copied from the embedded \PDF\ file, but instead a local font is opened, +and all needed glyphs will be taken from the Type~1 font file that is +mentioned in the map line (see \varname{fontfile} below). By this +collecting mechanism Type~1 glyphs can be shared between several +embedded \PDF\ files and with text that is typeset by \PDFTEX, which +helps keep the resulting \PDF\ file size smaller, if many files with +similar Type~1(C) fonts are embedded. Replacing Type~1 fonts from +embedded \PDF\ files requires that also a Type~1 font file name is in +the \varname{fontfile} field (see below). + +Second, if a font file is not to be embedded into the \PDF\ output +(\varname{fontfile} field missing), then the \varname{psname} field will +be copied to the \type{/BaseFont} and \type{/FontName} dictionary +entries in the \PDF\ file, so that the \POSTSCRIPT\ font name will be +known to viewers and other \PDF-reading applications. + +\subsection{Map lines: \emph{fontflags}} + +The \emph{fontflags} field optionally specifies various characteristics +of the font. The following description of these flags is taken, with +slight modification, from the \PDFReference\ (the section on font +descriptor flags). Viewers may adapt their rendering to these flags, +especially when they substitute for a non-embedded font. + +The value of the flags key in a font descriptor is a 32-bit integer that +contains a collection of boolean attributes. These attributes are true +if the corresponding bit is set to~1. The following table specifies the +meanings of the bits, with bit~1 being the least significant. Reserved +bits must be set to zero. + +\begin{smalltable} +\begin{tabular}{cl} +\bf bit position & \bf semantics \cr +1 & Fixed-width font \cr +2 & Serif font \cr +3 & Symbolic font \cr +4 & Script font \cr +5 & Reserved \cr +6 & Uses the Adobe Standard Roman character set \cr +7 & Italic \cr +8--16 & Reserved \cr +17 & All-capitals font \cr +18 & Small-capitals font \cr +19 & Force bold at small text sizes \cr +20--32 & Reserved \cr +\end{tabular} +\end{smalltable} + +The first several bits specify the general type of font. All characters +in a \emph{fixed-width} font (a.k.a.\ monospaced, typewriter) have the +same width, while characters in a proportional font have different +widths. Characters in a \emph{serif font} have short strokes drawn at an +angle on the top and bottom of character stems, while sans serif fonts +do not have such strokes. A \emph{symbolic font} contains symbols rather +than letters and numbers. Characters in a \emph{script font} resemble +cursive handwriting. An \emph{all-capitals} font, which is typically +used for display purposes such as titles or headlines, contains no +lowercase letters. It differs from a \emph{small-capitals} font in that +characters in the latter, while also capital letters, have been sized +and their proportions adjusted so that they have the same size and +stroke weight as lowercase characters in the same typeface family. + +Bit~6 in the flags field indicates that the font's character set +conforms to the Adobe Standard Roman Character Set, or a subset of that, +and that it uses the standard names for those characters. + +Finally, bit~19 is used to determine whether or not bold characters are +drawn with extra pixels even at very small text sizes. Typically, when +characters are drawn at small sizes on very low resolution devices such +as display screens, features of bold characters may appear only one pixel +wide. Because this is the minimum feature width on a pixel\hyph based device, +ordinary non\hyph bold characters also appear with one\hyph pixel wide features, +and thus cannot be distinguished from bold characters. If bit~19 is set, +features of bold characters may be thickened at small text sizes. + +If the \varname{fontflags} field is not given, and the font is embedded, +\PDFTEX\ treats it as the value~4 (decimal, that is, bit position 3 is +set), a symbolic font. For non-embedded fonts, the default value is +\type{0x22}, a non-symbolic serif font. If you do not know the correct +value, it is best not to specify it at all, as specifying a bad value of +font flags may cause trouble in viewers. On the other hand this option +is not absolutely useless because it provides backward compatibility +with older map files (see the \varname{fontfile} description below). + +\subsection{Map lines: \varname{special}} + +The \varname{special} field specifies font manipulations in the same way +as \type{dvips}. Currently only the keywords \type{SlantFont} and +\type{ExtendFont} are interpreted; other instructions (notably +\type{ReEncodeFont} and its parameters, see \varname{encoding} below) +are ignored. The permitted \type{SlantFont} range is $-1..1$; for +\type{ExtendFont} it's $-2..2$. The text of the \varname{special} field +must be enclosed by ASCII double quote characters: \type{"}. + +\subsection{Map lines: \varname{encodingfile}} + +The \varname{encodingfile} field specifies the name of the file +containing the external encoding vector to be used for the font. The +encoding file name must have the extension \type{.enc}, and the file +name including extension must be given with either a preceding~\type{<} +character or a preceding~\type{<[}. The format of the encoding vector is +identical to that used by \type{dvips}. If no encoding is specified, the +font's built\hyph in default encoding is used. The +\varname{encodingfile} field may be omitted if you are sure that the +font resource has the correct built-in encoding. In general this option +is highly recommended, and it is required when subsetting a TrueType +font. + +Starting with \PDFTEX\ version 1.40.19, an encoding file can also be +specified for bitmap \PK\ fonts. In this case, it assigns the glyph +names from the given encoding vector, which can be used with the +\cs{pdfglyphtounicode} primitive (q.v.). For example: + +\begin{verbatim} +\pdfglyphtounicode{ffi}{0066 0066 0069} % normally: \input glyphtounicode +\pdfgentounicode=1 +\pdfmapline{cmb10 <7t.enc} +\font\cmb=cmb10 \cmb ffi +\end{verbatim} + +The result is a \PDF\ file with a correctly-labeled \type{/ffi} +character instead of the numeric character position in \type{cmb10.tfm} +(decimal 14). + +\subsection{Map lines: \varname{fontfile}} + +The \varname{fontfile} field sets the name of the font file to be +embedded into the \PDF\ output for a given \TeX\ font; the +\varname{tfmname}~$\leftrightarrow$~\varname{fontfile} mapping is the +most prominent use of the \filename{pdftex.map} file. + +The font file name must refer to a Type~1 or TrueType font file. If the +\varname{fontfile} field is missing, no font embedding can take place; a +warning will be given, unless the \varname{psname} field contain one of +the 14 standard font names. Not embedding all fonts in a \PDF\ file is +troublesome, as this forces the \PDF\ viewer to use or synthesize a +replacement, typically with awful results. + +The font file name should be preceded by one or two special characters, +specifying how to handle the font file: + +\begin{itemize} +\item If the font file name is preceded by a \type{<} character + (as in \type{<cmr10.pfb}), the font file will be only partially + embedded in the \PDF\ output (``subsetted''), meaning that only + used glyphs are written to the \PDF\ file. This is the most + common use and is \emph{strongly recommended} for any font, as it + ensures the portability and reduces the size of the \PDF\ output. + Subsetted fonts are included in such a way that name and cache + clashes are minimized. + +\item If the font file name is preceded by a double \type{<<}, the font + file will be included entirely---all glyphs of the font are + embedded, including even those not used in the document. Apart + from increasing the \PDF\ output size, this option may cause + troubles with TrueType fonts, so it is normally not recommended + for Type~1 or TrueType fonts. But this is currently the only mode + that allows the use of OpenType fonts. This mode might also be + useful in case the font is atypical and cannot be subsetted well + by \PDFTEX. {\em Beware: proprietary font vendors typically + forbid full font inclusion.} + +\item As of \PDFTEX\ version 1.40.0, if no special character precedes + the font file name, it is ignored, with a warning. You achieve + exactly the same \PDF\ result if you just remove the font file + name from the map entry. Then the glyph widths that go into the + \PDF~file are extracted from the \TFM~file, and a font descriptor + object is created that contains approximations of the font + metrics for the selected font. + +\item Specifying the {\em psname} and no font file name is only useful + as a last-ditch fallback when you do not want to embed the font + (\eg\ due to font license restrictions), but wish to use the font + metrics and let the \PDF\ viewer generate instances that look + close to the used font, in case the font resource is not + installed on the system where the \PDF\ output will be viewed or + printed. To use this feature, the font flags {\em must} be + specified, and it must have the bit~6 set on, which means that + only fonts with the Adobe Standard Roman character set can be + simulated. The only exception is the case of a symbolic font. + In these days of Unicode, these font approximations are not + likely to be useful. +\end{itemize} + +If you encounter problematic lookups, for instance if \PDFTEX\ tries +to open a \type{.pfa} file instead of a \type{.pfb}, you can add +the suffix to the filename. In this respect, \PDFTEX\ completely relies +on the Kpathsea library. + +For Type~1 and TrueType fonts, the font file will be included only once +in the \PDF\ output, regardless of how many \TeX\ \cs{font} instances +are used in the document. For instance, given + +\begin{verbatim} +\font\a = cmr12 +\font\b = cmr12 at 11pt +\end{verbatim} + +the outline file \type{cmr12.pfb} will only be included once in the +\PDF, and merely scaled down to create the instance for \cs{b}. + +If a used font is not present in the map files, \PDFTEX\ will try to use +\PK~fonts as most \DVI\ drivers do, creating \PK~fonts on-the-fly if +needed. This is the normal, and recommended, way to use bitmap fonts. + +\subsection{Map lines: summary} + +To summarize this rather complex story, let's look at some more example +map lines. The most common way is to embed only a subset of glyphs from +a font for a particular desired encoding, here~\type{8r}: + +\begin{verbatim} +ptmri8r Times-Italic <8r.enc <ptmri8a.pfb +\end{verbatim} + +Without re-encoding it looks like this: + +\begin{verbatim} +cmr10 CMR10 <cmr10.pfb +\end{verbatim} + +\type{SlantFont} and \type{ExtendFont} fields are specified as with +\type{dvips}: + +\begin{verbatim} +psyro StandardSymL ".167 SlantFont" <usyr.pfb +pcrr8rn Courier ".85 ExtendFont" <8r.enc <pcrr8a.pfb +\end{verbatim} + +Entirely embed a font into the \PDF\ file without and with re-encoding +(not typically useful): + +\begin{verbatim} +fmvr8x MarVoSym <<marvosym.pfb +pgsr8r GillSans <8r.enc <<pgsr8a.pfb +\end{verbatim} + +A TrueType font can be used in the same way as a Type~1 font: + +\begin{verbatim} +verdana8r Verdana <8r.enc <verdana.ttf +\end{verbatim} + +Finally, a few cases with non-embedded fonts. If the font file is +missing, the viewer application will have to use its own approximation +of the missing font (with and without re-encoding): + +\begin{verbatim} +ptmr8r Times-Roman <8r.enc +psyr Symbol +\end{verbatim} + +In the final example the numerical font flags (bit position 6) specify +using the Adobe Standard Roman character set, so the viewer might try an +approximation: + +\begin{verbatim} +pgsr8r GillSans 32 +\end{verbatim} + +Not embedding fonts is rather risky and should generally be avoided. The +recommendation these days is to embed all fonts, even the 14 standard +ones. + +\section{Helper tools for TrueType fonts: \texttt{ttf2afm}} + +As mentioned above, \PDFTEX\ can work with TrueType fonts. Defining +TrueType fonts is similar to Type~1. The only extra thing to do with +TrueType is to create a \TFM\ file. There is a program called +\type{ttf2afm} in the \PDFTEX\ distribution which can be used to extract +\AFM\ from TrueType fonts (another conversion program is +\type{ttf2pt1}). Basic usage of \type{ttf2afm}: + +\begin{verbatim} +ttf2afm -e encfile.enc -o output.afm input.ttf +\end{verbatim} + +A TrueType file can be recognized by its suffix \filename{ttf}. +If no \type{-o} option is given, \type{ttf2afm} writes the output \AFM\ +to standard output. + +The optional \varname{encfile} specifies the encoding, which is the same +as the encoding vector used in map files for \PDFTEX\ and \type{dvips}. +That is, it must be an 8-bit encoding, not Unicode. If the encoding is +not given, all the glyphs of the \AFM\ output will be mapped to +\type{/.notdef}. If we need to know which glyphs are available in the +font, we can run \type{ttf2afm} without any \type{-e} to get all glyph +names. The resulting \AFM\ file can be used to generate a \TFM\ by +applying the \filename {afm2tfm} utility. + +To use a new TrueType font the minimal steps may look like below, supposing +that a map file \filename {test.map} is used. + +\begin{verbatim} +ttf2afm -e 8r.enc -o times.afm times.ttf +afm2tfm times.afm -T 8r.enc +echo "times TimesNewRomanPSMT <8r.enc <times.ttf" >>test.map +\end{verbatim} + +There are a limitations with TrueType fonts in comparison with +Type~1 fonts: + +\begin{itemize} +\item The special effects SlantFont\slash ExtendFont did not work + before version 1.40.0. +\item To subset a TrueType font, the font must be specified as re\hyph + encoded, therefore an encoding vector must be given. +\item TrueType fonts used in embedded \PDF\ files are kept + untouched; they are not replaced or merged with the same font + used in the document, as happens with Type~1. +\end{itemize} + +For much more about \PDFTEX\ and TrueType fonts, including many details +on handling glyph names, see ``A closer look at TrueType fonts and +\PDFTEX'', \titleref{TUGboat} 30:1 (2009), pp.~32\hyph 34, +\useurl{thanhtruetypetub}. + +\chapter{\PDFTEX\ primitives} +\label{sec.primitives} + +Here follows a description of the primitives added by \PDFTEX\ to the +original \TEX\ engine (other extensions by \ETEX, \MLTEX\ and \ENCTEX\ +are not described). Many of these primitives are described further in +the \filename {samplepdf.tex} file in the \PDFTEX\ distribution (q.v.). + +If the output is \DVI, then the \PDFTEX-specific dimension parameters +are not used at all. However, some \PDFTEX\ integer parameters can +affect \DVI\ as well as \PDF\ output (specifically, \cs{pdfoutput} and +\cs{pdfadjustspacing}). + +A warning to macro writers: if you define macros whose names start with +\cs{pdf}, you risk name clashes with new primitives that may be +introduced in future versions of \PDFTEX. + +General warning: many of these new primitives, for example \cs{pdfdest} +and \cs{pdfoutline}, write their arguments directly to the \PDF\ output +file (when producing \PDF), as \PDF\ string constants. This means that +\emph{you} (or, more likely, the macros you write) must escape +characters as necessary (namely \cs{}, \type{(}, and \type{)}. +Otherwise, an invalid \PDF\ file may result. The \type{hyperref} and +\TEXINFO\ packages have code which may serve as a starting point for +implementing this, although it will certainly need to be adapted to any +particular situation. + +\section{Document setup} + +\subsection{\cs{pdfoutput}} +\pdftexprimitive{\Syntax{\cs{pdfoutput} \Whatever{integer}}} + +This parameter specifies whether the output format should be \DVI\ or +\PDF. A positive value means \PDF\ output, otherwise (default 0) one +gets \DVI\ output. This primitive is the only one that must be set to +produce \PDF\ output (the command-line option \type{-output-format=pdf} +may alternatively be used); all other primitives are optional. This +parameter cannot be specified \emph{after} shipping out the first page. +In other words, to get \PDF\ output, we have to set \cs{pdfoutput} +before \PDFTEX\ the first page. + +A simple way of making macros aware of \PDFTEX\ in both \PDF\ or \DVI\ +mode is: + +\begin{verbatim} +\ifx\pdfoutput\undefined \csname newcount\endcsname\pdfoutput \fi +\ifcase\pdfoutput DVI CODE \else PDF CODE \fi +\end{verbatim} + +Using the \type{ifpdf.sty} file, which works with both \LATEX\ and plain +\TeX, is a cleaner way of doing this. Originally, the simple test +\verb|\ifx\pdfoutput\undefined| sufficed; but for many years, the +\PDFTEX\ engine is used in distributions also for non-\PDF\ formats +(\eg\ \LATEX), so \cs{pdfoutput} may be defined even when the output +format is \DVI. + +\subsection{\cs{pdfmajorversion}, \cs{pdfminorversion}} +\pdftexprimitive{\Syntax{\cs{pdfmajorversion} \Whatever{integer}}} +\pdftexprimitive{\Syntax{\cs{pdfminorversion} \Whatever{integer}}} + +Together, these two primitives specify the \PDF\ version for generated \PDF\ +output. The defaults compiled into the \PDFTEX\ program are +\cs{pdfmajorversion=1} and \cs{pdfminorversion=4}, thus \PDF~1.4 +is generated by default. + +However, distributions typically alter the engine's compiled default +minor version of~4 when building formats. For example, as of 2010, +\TEXLIVE\ sets \cs{pdfminorversion=5} when formats are built. This is +so object compression can be enabled (see \cs{pdfobjcompress} below). + +This value also defines the highest \PDF\ version for included \PDF{}s +to be allowed without error, by default (see +\cs{pdfinclusionerrorlevel}). + +The values for both must be $\ge1$ but are not checked further. +Furthermore, they are set independently; setting only +\cs{pdfmajorversion=2} would result in \PDF~2.4 output; it's +necessary to additionally set \cs{pdfminorversion}. + +If specified, these primitives must appear before any data is written to +the generated \PDF\ file. The \cs{pdfmajorversion} primitive was +introduced in \PDFTEX\ 1.40.21. \cs{pdfminorversion} was originally a +synonym of the \cs{pdfoptionpdfminorversion} command, which is now +obsolete. \introduced{1.30.0} + +\subsection{\cs{pdfcompresslevel}} +\pdftexprimitive{\Syntax{\cs{pdfcompresslevel} \Whatever{integer}}} + +This integer parameter specifies the level of stream compression. Zero +means no compression, 1~means fastest, 9~means best, $2..8$ means +something in between. A value outside this range will be adjusted to the +nearest meaningful value. This parameter is read each time \PDFTEX\ +starts a stream. + +This compression applies to text, inline graphics, and embedded \PNG\ +images (but only if they are un- and re-compressed during the embedding +process). It is implemented by the \type{zlib} library). + +Setting \cs{pdfcompresslevel=0} is useful for \PDF\ stream debugging. + +\subsection{\cs{pdfobjcompresslevel}} +\pdftexprimitive{\Syntax{\cs{pdfobjcompresslevel} \Whatever{integer}}} + +This integer parameter controls the compression of non-stream objects. +If specified, the parameter must appear before any data is written to +the \PDF\ output. \introduced{1.40.0} + +In the \PDF-1.4 specification, non-stream objects had to be written in +the \PDF\ file as clear text, uncompressed. The \PDF-1.5 specification +allows collecting non-stream objects as ``compressed objects'' into +``object stream'' objects (\type{/Type/ObjStm}, see the \PDFReference, +5th~ed., \S3.4.6). At the end of the \PDF\ file, an \type{/XRef} +cross-reference stream is then written out instead of the object table. +This can result in a considerably smaller \PDF\ file, particularly if +lots of annotations and links are used. + +The writing of compressed objects is enabled by setting +\cs{pdfobjcompresslevel} to a value between~1 and~3; it's disabled if~0 +(default). Object compression also requires +$\cs{pdfminorversion}\ge5$ (or $\cs{pdfmajorversion}\ge2$), else +a warning is given and the compression is disabled. The value of +\cs{pdfobjcompresslevel} is clipped to the range $0..3$, but using +values outside this range is not recommended (for future extension). + +Values for \cs{pdfobjcompresslevel} have the following effects: + +\begin{itemize} +\item When set to~0, no object streams are generated at all. + +\item When set to~1, +all non-stream objects are compressed with the exception of any objects +coming with embedded \PDF\ files (``paranoid'' mode, to avoid yet unknown +problems), and also the \type{/Info} dictionary is not compressed for +clear-text legibility. + +\item When set to~2, also all non-stream objects coming +with embedded \PDF\ files are compressed, but the \type{/Info} dictionary +is still not compressed. + +\item Finally, when set to~3, all non-stream objects +are compressed, including the \type{/Info} dictionary (this means that +the \type{/Info} can't be read as clear text any more). If object streams +are to be used, currently \cs{pdfobjcompresslevel=2} is recommended, +and is so specified in some distributions, including \TEXLIVE~2010 and later. +\end{itemize} + +\emph{Compatibility caveats:} \PDF\ files generated with object +streams enabled can't be read with (sufficiently old) \PDF\ viewers that +don't understand \PDF-1.5 files. For widest distribution and unknown +audience, don't activate object stream writing. The \PDF-1.5 standard +describes also a hybrid object compression mode that gives some backward +compatibility, but this is currently not implemented, as \PDF-1.5 was +rather quickly adopted by modern \PDF\ viewers. Also not implemented is +the optional \type{/Extends} key. + +\subsection{\cs{pdfdecimaldigits}} +\pdftexprimitive{\Syntax{\cs{pdfdecimaldigits} \Whatever{integer}}} + +This integer parameter specifies the numeric accuracy of real +coordinates as written to the \PDF\ file. It gives the maximal number of +decimal digits after the decimal point. Valid values are in the range +$0..4$. A higher value means more precise output, but also results in a +larger file size and more time to display or print. In most cases the +optimal value is~2. This parameter does not influence the precision of +numbers used in raw \PDF\ code, like that used in \cs{pdfliteral} and +annotation action specifications; also multiplication items (\eg\ +scaling factors) are not affected and are always output with best +precision. This parameter is read when \PDFTEX\ writes a real number to +the \PDF\ output. + +When including huge \METAPOST\ images using \filename {supp-pdf.tex}, one can +limit the accuracy to two digits with \cs{twodigitMPoutput}. + +\subsection{\cs{pdfhorigin}} +\pdftexprimitive{\Syntax{\cs{pdfhorigin} \Whatever{dimen}}} + +This parameter can be used to set the horizontal offset of the output +box from the top left corner of the page. A value of 1~inch corresponds +to the normal \TEX\ offset. This parameter is read when \PDFTEX\ starts +shipping out a page to the \PDF\ output. + +For all normal purposes, this parameter should always be kept at 1~true +inch. If you want to shift text on the page, use \TEX's own \cs{hoffset} +primitive. To avoid surprises, after global magnification has been +changed by the \cs{mag} primitive, the \cs{pdfhorigin} parameter should +still be 1~true inch, \eg\ by setting \cs{pdfhorigin=1 true in} after +the \cs{mag} setting. Or, you can preadjust the \cs{pdfhorigin} value +before typing \cs{mag}, so that its value after the \cs{mag} command +ends up at 1~true inch again. + +\subsection{\cs{pdfvorigin}} +\pdftexprimitive{\Syntax{\cs{pdfvorigin} \Whatever{dimen}}} + +This parameter is the vertical companion of \cs{pdfhorigin}, and the +notes above regarding \cs{mag} and true dimensions apply. Also keep +in mind that the \TEX\ coordinate system starts in the top left corner +(downward), while \PDF\ coordinates start at the bottom left corner +(upward). + +\subsection{\cs{pdfpagewidth}} +\pdftexprimitive{\Syntax{\cs{pdfpagewidth} \Whatever{dimen}}} + +This dimension parameter specifies the page width of the \PDF\ output +(the screen, the paper, etc.). \PDFTEX\ reads this parameter when it +starts shipping out a page. If magnification has been changed by the +\cs{mag} primitive, check that this parameter reflects the desired true +page width. When part of the page falls off the paper or screen, it's +quite possible that this parameter is set wrong. + +If the value is set to zero, the page width is calculated as + +\[ +\hbox{\textit{width}}_{\hbox{\scriptsize box being shipped out}} ++ 2 \times (\cs{horigin} + \hbox{\cs{hoffset}}). +\] +It is not wise to rely on this default calculation, since box widths may +vary unexpectedly. + +\subsection{\cs{pdfpageheight}} +\pdftexprimitive{\Syntax{\cs{pdfpageheight} \Whatever{dimen}}} + +Similar to the previous item, this dimension parameter specifies the +page height of the \PDF\ output; the notes above apply. If set to zero, +the page height will be calculated analogously to the above. + +\section{Document info and catalog} +\label{sec.docinfocatalog} + +\subsection{\cs{pdfomitinfodict}} +\pdftexprimitive{\Syntax{\cs{pdfomitinfodict} \Whatever{integer}}} + +If nonzero, omit the \type{/Info} dictionary completely, as required by +the \PDF\ A-4 standard. \introduced{1.40.25} + +\subsection{\cs{pdfinfo}} +\pdftexprimitive{\Syntax{\cs{pdfinfo} \Something{general text}}} + +This primitive allows the user to specify information for the document +info dictionary. Provided information can be extracted from the output +\PDF\ by, for instance, the \type{pdfinfo} program. + +The \Something{general text} is a collection of key\hyph value\hyph +pairs. The key names are preceded by a \type{/}, and the values, being +strings, are given between parentheses. All keys, and the primitive +itself, are optional. Possible +keys are:\newline +\type{/Title},\newline +\type{/Author},\newline +\type{/Subject},\newline +\type{/Keywords},\newline +\type{/Producer} (defaults to \hbox{\tt pdfTeX-\currentpdftex}),\newline +\type{/Creator} (defaults to \type{TeX}),\newline +\type{/CreationDate} (defaults to current date and time, with time zone),\newline +\type{/ModDate} (same default),\newline +\type{/Trapped} (defaults to \type{/False},\newline +\type{/PTEX.Fullbanner} (defaults to the \cs{pdftexbanner} string, q.v.). + +\type{/CreationDate} and \type{/ModDate} are expressed in the form +\type{D:YYYYMMDDhhmmssTZ}, where `\type{D:}' is a constant string +prefix, \type{YYYY} is the year, \type{MM} is the month, \type{DD} is +the day, \type{hh} is the hour, \type{mm} is the minutes, \type{ss} is +the seconds, and \type{TZ} is an optional string denoting the time zone, +\type{Z} for universal time. For example, this is the Unix epoch, the +beginning of 1970-01-01 UTC, in this format: \type{D:19700101000000Z}. +If the time zone is not UTC, it is given as \type{+HH'mm'} or +\type{-HH'mm'}, indicating an offset of the given hours and minutes from +UTC, with the given either later (\type{+}) or earlier (\type{-}) than +UTC. For more details, see the \PDFReference, \S7.9.4. + +Multiple appearances of \cs{pdfinfo} are concatenated. Usually if a key +is given more than once, the first appearance will be used, but this is +viewer\hyph dependent. Except for standard \TeX\ macro expansion, +\PDFTEX\ does not perform any further operations in the +\Something{general text} provided by the user. + +Here is an example of using \cs{pdfinfo} to include the +information not supplied by \PDFTEX: + +\begin{verbatim} +\pdfinfo { + /Title (example.pdf) + /Author (Tom and Jerry) + /Subject (Example) + /Keywords (mouse, cat) +} +\end{verbatim} + +\subsection{\cs{pdfinfoomitdate}} +\pdftexprimitive{\Syntax{\cs{pdfinfoomitdate} \Whatever{integer}}} + +If nonzero, omit the \type{/CreationDate} and \type{/ModDate} keys from +the document info dictionary described above. This can be useful in +making reproducible \PDF{}s. \introduced{1.40.17} + +\subsection{\cs{pdfsuppressptexinfo}} +\pdftexprimitive{\Syntax{\cs{pdfsuppressptexinfo} \Whatever{integer}}} + +This value is treated as a bit mask, specifying which \type{PTEX.*} keys +to omit from the output: + +\begin{smalltable} +\begin{tabular}{cl} +\bf value & \bf suppresses \cr + 1 & \type{PTEX.Fullbanner} \cr + 2 & \type{PTEX.FileName} \cr + 4 & \type{PTEX.PageNumber} \cr + 8 & \type{PTEX.InfoDict} \cr +\end{tabular} +\end{smalltable} + +\noindent Thus, the value \type{-1}, setting all the bits, suppresses +everything. + +\type{PTEX.Fullbanner} is included by default in the general document +info dictionary, as mentioned under \cs{pdfinfo} above. The other +\type{PTEX.*} keys are included when a \PDF\ is included in the document +(and not otherwise), as described in section~\ref{sec.addpdfkeys}. + +This conditional suppression can be useful in making reproducible +\PDF{}s. \introduced{1.40.17} + +\subsection{\cs{pdfcatalog}} +\pdftexprimitive{\Syntax{\cs{pdfcatalog} \Something{general text} + \Optional{\Literal{openaction} \Something{action spec}}}} + +Similar to the document info section is the document catalog, where +possible keys are \type{/URI}, which specifies the base \URL\ of the +document, and \type {/PageMode}, which determines how the \PDF\ viewer +displays the document on startup. The possibilities for the latter are +given in this table: + +\begin{smalltable} +\begin{tabular}{ll} +\bf value & \bf meaning \cr +\tt /UseNone & neither outline nor thumbnails visible \cr +\tt /UseOutlines & outline visible \cr +\tt /UseThumbs & thumbnails visible \cr +\tt /FullScreen & full\hyph screen mode \cr +\end{tabular} +\end{smalltable} + +The default \type{/PageMode} setting is \type{/UseNone}. In full\hyph +screen mode, there is no menu bar, window controls, nor any other window +present. + +After the \Something{general text} of the catalog, a construct +\Literal{openaction} \Something{action spec} can be given, where +\Literal{openaction} is a \PDFTEX\ keyword, and \Something{action spec} +specifies the action to be taken when opening the document. This +\Something{action spec} is the same as for internal links; see +section~\ref{sec.linking}. + +Several settings can be made in one \cs{pdfcatalog} call, for +example: + +\begin{verbatim} +\pdfcatalog { + /PageMode /FullScreen +} openaction goto page 2 {/Fit} +\end{verbatim} + +\subsection{\cs{pdfcreationdate}} +\pdftexprimitive{\Syntax{\cs{pdfcreationdate} \Whatever{expandable}}} + +Expands to the date string \PDFTEX\ uses in the info dictionary of the +document, \eg\ for this file: {\tt\pdfcreationdate}. \introduced{1.30.0} + +\subsection{\cs{pdfnames}} +\pdftexprimitive{\Syntax{\cs{pdfnames} \Something{general text}}} + +This primitive inserts the \Something{general text} to the \type{/Names} +array. The text must conform to the specifications as laid down in the +\PDFReference, or the document may be invalid. + +\subsection{\cs{pdftrailer}} +\pdftexprimitive{\Syntax{\cs{pdftrailer} \Something{general text}}} + +This command puts its argument text verbatim into the file trailer +dictionary. Example: \verb|\pdftrailer{/mytrlrkey /mytrlrval}|. +\introduced{1.11a} + +\subsection{\cs{pdftrailerid}} +\pdftexprimitive{\Syntax{\cs{pdftrailerid} \Something{general text}}} + +Use the \Something{general text} to seed the \type{/ID} value in the +trailer, instead of the default combination of the input file +name and starting time. If the argument is empty, the \type{/ID} is +omitted entirely. Example: \verb|\pdftrailerid{}|. This can be useful +in making reproducible \PDF{}s. \introduced{1.40.17} + +\section{Fonts} + +\subsection{\cs{pdfadjustspacing}} +\pdftexprimitive{\Syntax{\cs{pdfadjustspacing} \Whatever{integer}}} + +This primitive controls whether font expansion happens (this operation +is described in detail at \cs{pdffontexpand}). By default, +\cs{pdfadjustspacing} is set to~0; then font expansion is disabled, so +that the \PDFTEX\ output is identical to that from the original \TEX\ +engine. + +Font expansion can be activated in two modes. When \cs{pdfadjustspacing} +is set to~1, font expansion is applied \emph{after} \TEX's normal +paragraph breaking routines have broken the paragraph into lines. In +this case, line breaks are identical to standard \TEX\ behavior. + +When set to~2, the width changes that are the result of stretching and +shrinking are taken into account \emph{while} the paragraph is broken +into lines. In this case, line breaks are likely to be different from +those of standard \TEX. Paragraphs may well become longer or shorter. + +Both alternatives require a collection of \TFM\ files that are +related to the \Something{stretch} and \Something{shrink} settings +for the \cs{pdffontexpand} primitive, unless this is given with the +\type{autoexpand} option. + +\subsection{\cs{pdffontexpand}} +\pdftexprimitive{\Syntax{\cs{pdffontexpand} + \Something{font} \Something{stretch} \Something{shrink} + \Something{step} \Optional{\Literal{autoexpand}}}} + +This extension to \TEX's font definitions controls a major \PDFTEX\ +feature called \emph{font expansion}. To enable font expansion, +\cs{pdfadjustspacing} must be set to a value greater than zero. We +describe the basic process with an example: + +\begin{verbatim} +\font\somefont=sometfm at 10pt +\pdffontexpand\somefont 30 20 10 autoexpand +\pdfadjustspacing=2 +\end{verbatim} + +The \verb|30 20 10| means this: ``hey \TEX, when line breaking is going +badly, you may stretch the glyphs from this font as much as 3\% or +shrink them as much as 2\%.'' For practical reasons \PDFTEX\ uses +discrete expansion steps, in this example, 1\%. + +Roughly speaking, the idea is as follows: When \TEX\ cannot break a line +in the appropriate way, the unbreakable parts of the last word may stick +into the margin. When \PDFTEX\ sees this, it will try to scale (shrink) +the glyphs in that line using fixed steps, until the line fits. When +lines are too spacey, the opposite happens: \PDFTEX\ starts scaling +(stretching) the glyphs until the white space gaps are acceptable. This +glyph stretching and shrinking is called \emph{font expansion}. + +There are two different modes for font expansion, depending on whether +\type{autoexpand} is specified: + +\begin{enumerate} +\item If the \type{autoexpand} keyword is given---this is +recommended mode---only a single map entry is needed for all expanded +font versions, using the name of the unexpanded \TFM\ file +(\varname{tfmname} in section~\ref{sec.map-tfmname}). No expanded +\varname{tfmname} versions need be mentioned (indeed, they are ignored), +as \PDFTEX\ generates expanded instances of the unexpanded \TFM\ data +structures and keeps them in its memory. As of \PDFTEX~1.40.0, the +\type{autoexpand} work is done within the page stream by modification of +the text matrix (\PDF\ operator ``\type{Tm}''), and not at the font file +level, giving the advantage that it now works not only with Type~1 but +also with TrueType and OpenType fonts (and even without embedding a font +file; but that's not recommended). In this mode \PDFTEX\ requires only +unexpanded font files. + +\item Second, if the \type{autoexpand} keyword is not given, setting up +font expansion requires considerably more work, as there must be map +entries for \TFM\ files in all required expansion values. The expanded +\varname{tfmname} variants are constructed by adding the font expansion +value to the \varname{tfmname} of the base font, \eg\ there must be a +map entry with \varname{tfmname} \type{sometfm+10} for 1\% stretch or +\type{sometfm-15} for 1.5\% shrink. This also means that for each +expanded font variant a \TFM\ file with properly expanded metrics must +exist. In addition to the \TFM\ file, it is necessary to provide, for +each expansion value, an individually crafted font file with the +expanded glyphs. Thus, this allows the absolute best possible output, +controlling the glyphs for every expanded variant of the font. It is a +rare document indeed for this to be worth the trouble. + +One technical drawback of non-\type{autoexpand} mode is that all needed +individual font files need to be embedded in the \PDF\ output for each +expanded font, leading to significantly larger \PDF\ files than in +\type{autoexpand} mode. + +Another caveat for non-\type{autoexpand} mode: when \cs{pdffontexpand} +is executed, \PDFTEX\ immediately loads two fonts, at the maximum +stretch and shrink; in our example, \type{sometfm+30} and +\type{sometfm-20}. (If they aren't available, \type{mktextfm} may be +uselessly called, and then an error message issued.) This happens even +if those fonts never end up being used, which is arguably undesirable, +but hard to change. It is not a problem when using \type{autoexpand}. +\end{enumerate} + +The font expansion mechanism is inspired by an optimization first +introduced by Prof.~Hermann Zapf, which in itself goes back to +optimizations used in the early days of typesetting: use different +glyphs to optimize the grayness of a page. So, there are many, slightly +different~a's, e's, etc. For practical reasons \PDFTEX\ does not use +such huge glyph collections; it uses horizontal scaling instead. This is +sub\hyph optimal, and possibly offensive to the design, though the +expansions are tiny. It is up to the user to decide whether such +slightly remastered fonts are acceptable. As an example, this +document is typeset with font expansion and margin kerning activated +(via the \texttt{microtype} \LaTeX\ package). + +\subsection{\cs{efcode}} +\pdftexprimitive{\Syntax{\cs{efcode} \Something{font} + \Something{8-bit number} \Whatever{integer}}} + +We haven't yet told the whole story. One can imagine that some glyphs +are visually more sensitive to stretching or shrinking than others. Then +the \cs{efcode} primitive can be used to influence the expandability of +individual glyphs within a given font, as a factor applied to the +expansion setting from the \cs{pdffontexpand} primitive. The syntax is +similar to \cs{sfcode} (but with the \Something{font} required), and it +defaults to~1000, meaning 100\% expandability. The given integer value +is clipped to the range $0..1000$, corresponding to a usable +expandability range of $0..100$\%. Examples: + +\begin{verbatim} +\efcode\somefont`A=800 +\efcode\somefont`O=0 +\end{verbatim} + +Here the A in \cs{somefont} may only stretch or shrink by up to 80\% of +the current expansion value for that font, and expansion for the~O is +disabled. The actual expansion is still bound to the steps as defined by +\cs{pdffontexpand} primitive. + +Changes to this table are global, \ie\ ignore \TeX's usual grouping, +and apply only to the given \Something{font}. + +\subsection{\cs{pdfprotrudechars}} +\pdftexprimitive{\Syntax{\cs{pdfprotrudechars} \Whatever{integer}}} + +Yet another way of optimizing paragraph breaking is to let certain +characters move into the margin (`character protrusion'). Character +protrusion is disabled when \cs{pdfprotrudechars=0} or negative. + +When \cs{pdfprotrudechars=1}, the glyphs qualified as such will make +this move when applicable, without changing the line-breaking. When +\cs{pdfprotrudechars=2} (or greater), character protrusion will be taken +into account while considering breakpoints, so line-breaking might be +changed. This qualification and the amount of shift are set by the +primitives \cs{rpcode} and \cs{lpcode}. + +If you want to protrude an item other than a character (\eg\ an +\cs{hbox}), you can do so by padding the item with an invisible +zero\hyph width character for which protrusion is activated. + +\subsection{\cs{rpcode}, \cs{lpcode}} +\pdftexprimitive{\Syntax{\cs{rpcode} \Something{font} + \Something{8-bit number} \Whatever{integer}}} +\pdftexprimitive{\Syntax{\cs{lpcode} \Something{font} + \Something{8-bit number} \Whatever{integer}}} + +The amount that a character from a given font may shift into the right +margin (`character protrusion') is set by the primitive \cs{rpcode}. The +protrusion distance is the integer value given to \cs{rpcode}, +multiplied by 0.001em from the current font. The given integer value is +clipped to the range $-1000..1000$, corresponding to a usable protrusion +range of $-$1em..1em. \cs{lpcode} is exactly analogous to \cs{rpcode}, +but affects the amount by which characters may protrude into the left +margin. + +Examples: + +\begin{verbatim} +\rpcode\somefont`,=200 +\rpcode\somefont`-=150 +\end{verbatim} + +Here the comma may shift by 0.2em into the margin and the hyphen by +0.15em. All these small bits and pieces will help \PDFTEX\ to give +you better paragraphs (use \cs{rpcode} judiciously; don't overdo it). + +Remark: old versions of \PDFTEX\ use the character width as measure. This +was changed to a proportion of the em-width after \THANH\ finished his +master's thesis. + +Changes to these tables are global, \ie\ ignore \TeX's usual grouping, +and apply only to the given \Something{font}. + +\subsection{\cs{leftmarginkern}, \cs{rightmarginkern}} +\pdftexprimitive{\Syntax{\cs{leftmarginkern} \Something{box number} + \Whatever{expandable}}} +\pdftexprimitive{\Syntax{\cs{rightmarginkern} \Something{box number} + \Whatever{expandable}}} + +The \cs{leftmarginkern} \Something{box number} primitive expands to the +width of the margin kern at the left side of the horizontal list stored +in \cs{box} \Something{box number}. The expansion string includes the +unit \type{pt}. \Eg\ when the left margin kern of \cs{box0} amounts to +$-$10pt, \cs{leftmarginkern0} will expand to \type{-10pt}. The primitive +\cs{rightmarginkern} works analogously for the right margin. +\introducedplural{1.30.0} + +These are auxiliary primitives to make character protrusion more +versatile. When using the \TEX\ primitives \cs{unhbox} or \cs{unhcopy}, +the margin kerns at either end of the unpackaged hbox will be removed +(\eg\ to avoid weird effects if several hboxes are unpackaged behind +each other into the same horizontal list). These \cs{unhbox} or +\cs{unhcopy} commands are often used together with \cs{vsplit} for dis- +and re\hyph assembling of paragraphs, \eg\ to add line numbers. +Paragraphs treated like this do not show character protrusion by +default, as the margin kerns have been removed during the unpacking +process. + +The \cs{leftmarginkern} and \cs{rightmarginkern} primitives allow +access to the margin kerns and store them away before unpackaging the +hbox. \Eg\ the following code snippet restores margin kerning of +a horizontal list stored in \cs{box}\cs{testline}, resulting in a hbox with +the original margin kerning, now inserted by ordinary kerns. + +\begin{verbatim} +\dimen0=\leftmarginkern\testline +\dimen1=\rightmarginkern\testline +\hbox to\hsize{\kern\dimen0\unhcopy\testline\kern\dimen1} +\end{verbatim} + +\subsection{\cs{letterspacefont}} +\pdftexprimitive{\Syntax{\cs{letterspacefont} \Something{control sequence} + \Something{font} \Something{integer}}} + +This primitive creates an instance of \Something{font} with the widths +of all glyphs increased by \Something{integer} thousandths of an em (as +defined by \Something{font}). The effect is letter spacing, but the +glyphs are actually wider, as the sidebearings are increased, so a +single glyph will take more space. For instance, the following creates a +font \cs{lsfont} whose glyphs are all 1.2pt larger than those of +\cs{normalfont}: + +\begin{verbatim} +\font\normalfont=myfont at 12pt +\letterspacefont\lsfont\normalfont 100 +\end{verbatim} + +Negative values are allowed for \Something{integer}. +Letter spacing works natively in \PDF\ mode only, unless special fonts are +devised (in our example, a \type{myfont+100ls} font), as with font expansion. + +\subsection{\cs{pdfcopyfont}} +\pdftexprimitive{\Syntax{\cs{pdfcopyfont} \Something{control sequence} + \Something{font}}} + +This primitive defines \Something{control sequence} as a synonym for +\Something{font}. + +\subsection{\cs{pdffakespace}} +\pdftexprimitive{\Syntax{\cs{pdffakespace}}} + +Always insert a fake interword space in the output (PDF only; this +primitive is an error in DVI mode), regardless of the values of +\cs{pdfinterwordspaceon} and \cs{pdfinterwordspaceoff} (q.v.). Example: + +\begin{verbatim} +Text with a fake interword \pdffakespace space. +\end{verbatim} +\introduced{1.40.15} + +\subsection{\cs{pdffontattr}} +\pdftexprimitive{\Syntax{\cs{pdffontattr} \Something{font} + \Something{general text}}} + +This primitive inserts the \Something{general text} into the +\type{/Font} dictionary. The text must conform to the specifications as +laid down in the \PDFReference, or the document may be invalid. For +examples, see the \type{cmap} and \type{CJK} packages. + +\subsection{\cs{pdffontname}} +\pdftexprimitive{\Syntax{\cs{pdffontname} \Something{font} + \Whatever{expandable}}} + +In \PDF\ files produced by \PDFTEX\ one can recognize a font resource +by the prefix~\type{/F} followed by a number, for instance \type{/F12} +or \type{/F54}. For a given \TEX\ \Something{font}, this primitive +expands to the number from the corresponding font resource name. +\Eg\ if \type{/F12} corresponds to some \TEX\ font \cs{foo}, then +\cs{pdffontname}\cs{foo} expands to the number~\type{12}. + +In the current implementation, when \cs{pdfuniqueresname} (see below) +is set to a positive value, the \cs{pdffontname} still returns only the +number from the font resource name, without the appended random string. + +\subsection{\cs{pdffontobjnum}} +\pdftexprimitive{\Syntax{\cs{pdffontobjnum} \Something{font} + \Whatever{expandable}}} + +This command is similar to \cs{pdffontname}, but it returns the \PDF\ +object number of the font dictionary instead of the number from the font +resource name. \Eg\ if the font dictionary (\type{/Type/Font}) in \PDF\ +object~3 corresponds to some \TEX\ font \cs{foo}, then +\cs{pdffontobjnum}\cs{foo} gives the number~\type{3}. + +Use of \cs{pdffontname} and \cs{pdffontobjnum} allows users full +access to all the font resources used in a document. + +\subsection{\cs{pdffontsize}} +\pdftexprimitive{\Syntax{\cs{pdffontsize} \Something{font} + \Whatever{expandable}}} + +This primitive expands to the font size of the given font, with unit +\type{pt}. \Eg\ when using the plain \TeX\ macro package, the call +\cs{pdffontsize}\cs{tenrm} expands to \type{10.0pt}. + +\subsection{\cs{pdfgentounicode}} +\pdftexprimitive{\Syntax{\cs{pdfgentounicode} \Whatever{integer}}} + +By default, \PDFTEX\ does not include a \type{/ToUnicode} resource when +including fonts in the output. Such a resource (also called a CMap +resource) maps glyph names to Unicode characters in a \PDF\ file. +Lacking such a resource, it is the \PDF\ reader which determines how and +whether searching in the \PDF\ file works. In practice, searching for +basic \ASCII\ characters generally works, but searching for anything +beyond those, including ligatures such as `fi', is likely to fail. + +If \cs{pdfgentounicode} is set to \type{1} when the job ends, the +\type{/ToUnicode} resource will be included in the output, with mappings +for Type~1 fonts used---unless \cs{pdfnobuiltintounicode} (q.v.) is set +for a given font. + +The mapping is created as follows: for each glyph in the font, look for +its \type{ToUnicode} value in a global hash table. By default that +global hash table is empty, in which case \PDFTEX\ merely emits a +warning. Entries are added to the table using the command +\cs{pdfglyphtounicode}, described next. + +\subsection{\cs{pdfglyphtounicode}} +\pdftexprimitive{\Syntax{\cs{pdfglyphtounicode} \Something{general text} + \Something{general text}}} + +The first argument is the name of a glyph, the second is a string of Unicode +numeric values denoting characters, separated by spaces. For instance: + +\begin{verbatim} +\pdfgentounicode=1 +\pdfglyphtounicode{ff}{0066 0066} +\end{verbatim} + +\noindent maps the \type{ff} ligature to a pair of \type{f} characters +(whose code is \type{U+0066}, that is, \ASCII\ \type{0x66}). + +Once a single \cs{pdfglyphtounicode} definition is made, whether it is +used or not, another feature comes into play: all glyph names of the +form \type{uniXXXX} or \type{uXXXX} are mapped to the natural +\type{U+XXXX}. Many fonts use this style of naming. + +In addition, the \type{glyphtounicode.tex} file (distributed with +\PDFTEX\ and other software) contains thousands of such definitions, +covering most common glyph names. So, for practical purposes, one would +probably want: + +\begin{verbatim} +\input glyphtounicode +\pdfgentounicode=1 +\end{verbatim} + +\noindent (\LATEX\ users could load the \type{cmap} package to achieve +the same effect.) + +By default, these glyph name-to-unicode mappings are global. Thus, + +\begin{verbatim} +\pdfglyphtounicode{abc}{1234} +\end{verbatim} + +\noindent would map the glyph named \type{abc} to \type{U+1234} for +every font. However, it's possible to make a mapping for a single font +using a \type{tfm:} prefix: + +\begin{verbatim} +\pdfglyphtounicode{tfm:foo/abc}{5678} +\end{verbatim} + +\noindent means that for the font \type{foo.tfm}, only, the glyph +\type{abc} is mapped to \type{U+5678}. + +Glyph names sometimes contain a dot, as in \type{somechar.sc}. \PDFTEX\ +simply strips the dot and everything after it before looking up the +name, so in this case it would look for \type{somechar} (even if +\type{somechar.sc} exists in the mappings, it will not be used). This +behavior could be made smarter if there is a demand for it. + +\subsection{\cs{pdfincludechars}} +\pdftexprimitive{\Syntax{\cs{pdfincludechars} \Something{font} + \Something{general text} \Whatever{expandable}}} + +This command causes \PDFTEX\ to treat the characters in \Something{general +text} as if they were used with \Something{font}, which means that the +corresponding glyphs will be embedded into the font resources in the \PDF\ +output. Nothing is appended to the list being built. + +\subsection{\cs{pdfinterwordspaceon}, \cs{pdfinterwordspaceoff}, + \cs{pdfspacefont}} +\pdftexprimitive{\Syntax{\cs{pdfinterwordspaceon}}} +\pdftexprimitive{\Syntax{\cs{pdfinterwordspaceoff}}} +\pdftexprimitive{\Syntax{\cs{pdfspacefont} \Something{general text}}} + +The first two commands insert corresponding whatsit nodes which turn +on/off generation of faked interword spaces in the \PDF\ output (they +cause errors in \DVI\ output). This allows for better reflowing of text +on the fly by \PDF\ readers, better extraction of textual content, and +is required by \PDF/A. It does not affect the normal \TeX\ justification +with glue of the typeset output. + +This works roughly as follows: with \cs{pdfinterwordspaceon}, +\PDFTEX\ will guess when an interword space should be inserted, based on +movement within some limits in horizontal direction. When found, +\PDFTEX\ inserts a true space character into the \PDF\ page description +for the viewers, and adjusts the next movement so that the next +character will be in the expected position, according to normal \TEX\ +behavior. + +Where does that ``true space character'' come from? +There are two possibilities. + +\begin{itemize} +\item If the current font has a real space character, it is used. +\PDFTEX\ considers a font to have such a space character if 1)~the font +has an encoding vector (\type{.enc} file) specified in its map entry, +and 2)~the encoding has a glyph named \type{space} (that is, the +PostScript name \type{/space}) at slot 32. For example, the font +\type{texnansi-lmr10} uses the encoding file \type{lm-texnansi.enc}, +which has such an entry. + +\item +If the current font does not have such a space character (this is the +case for most traditional \TEX\ fonts, such as \type{cmr10} and +\type{ec-lmr10}), \PDFTEX\ will use the space character from a special +fallback font named (by default) \type{pdftexspace}[\type{.tfm}]. +\PDFTEX\ automatically defines a map entry for this font which looks +like this: + +\begin{verbatim} +\pdfmapline{=pdftexspace PdfTeX-Space <pdftexspace.pfb} +\end{verbatim} + +The \type{pdftexspace.tfm} and \type{pdftexspace.pfb} files are expected +to be available to \PDFTEX\ just like any other font. (They are +distributed with \PDFTEX.) The \type{pdftexspace} font was constructed +by hand; it has a space character that is .333em (and no other +characters). + +A different fallback font for the space character can be given via +\verb|\pdfspacefont{myfont}|. This is most likely to be useful for +testing and debugging. In this case, \PDFTEX\ assumes that the given font +has a real space character at slot 32, and that any necessary +corresponding map entry exists. For example: + +\begin{verbatim} +\pdfspacefont{texnansi-lmr10} % use space char from this font if + % current font has no space char +\end{verbatim} +\end{itemize} + +History: Before \PDFTEX\ version 1.40.25, no check was made for a +\type{space} character in the current font, the fallback font was named +\type{dummy-space}, and its space character was tiny, 0.001em. It turned +out that \PDF\ viewers were unhappy with this tiny space, especially +with tagged \PDF. + +Example of usage (see also the \type{fake-interword-space.tex} test file): + +\begin{verbatim} +Text with no interword spaces. + +\pdfglyphtounicode{space}{0020} +\pdfinterwordspaceon + +Switch to text with faked interword spaces. + +\pdfinterwordspaceoff + +Back to text with no interword spaces. +\end{verbatim} +\introducedplural{1.40.15, 1.40.25} + +\subsection{\cs{pdfmapfile}} +\pdftexprimitive{\Syntax{\cs{pdfmapfile} \Something{map filename}}} + +This primitive is used for reading a font map file consisting of one or +more font map lines. The name of the map file is given in the +\Something{map filename} together with an optional leading modifier +character, as explained below. If your map file isn't in the current +directory or a standard system directory, you will need to set the +\type{TEXFONTMAPS} variable (in \WEBC) or give an explicit path so that +it will be found. + +If no \cs{pdfmapfile} primitive is given, the default map file +\filename{pdftex.map} will be read by \PDFTEX. Normally there is no need +for a \PDFTEX\ user to bother about the \cs{pdfmapfile} or +\cs{pdfmapline} primitives, as the main \TEX\ distributions provide +helper tools to automatically assemble the default \type{pdftex.map}. +(In \TEXLIVE, these tools are \type{updmap} and \type{updmap-sys}.) + +There is a companion primitive \cs{pdfmapline} that allows scanning +single map lines; its map line argument has the same syntax as the map +lines from a map file. Both primitives can be used concurrently. The +\cs{pdfmapfile} primitive is fast for reading external bulk font map +information (many map lines collected in a map file), whereas the +\cs{pdfmapline} allows putting the font map information for individual +\TeX\ fonts directly in the \TeX\ source or a style file. With both +primitives, the map line information is scanned by \PDFTEX\ identically. +In the most common case, the data are put into a fresh internal map +entry data structure, which is then consulted when a font is used. + +When a \cs{pdfmapfile} or \cs{pdfmapline} primitive is executed by +\PDFTEX, the argument (map file or map line) will be processed +immediately, and the internal map entry database updated. The operation +mode of the \cs{pdfmapfile} and \cs{pdfmapline} primitives is selected +by an optional modifier character, one of \type{+}, \type{=}, \type{-}, +in front of the \varname{tfmname} field. This modifier defines how the +individual map lines are going to be handled, and how a collision +between an already registered map entry and a newer one is resolved: +either by ignoring a later entry, or replacing or deleting an existing +entry. In any case, map entries of fonts already in use are kept +untouched. Here are two examples: + +\begin{verbatim} +\pdfmapfile{+myfont.map} +\pdfmapline{+ptmri8r Times-Italic <8r.enc <ptmri8a.pfb} +\end{verbatim} + +When no modifier character is given (\eg\ \verb|\pdfmapfile{foo.map}| +or\newline \verb|\pdfmapline{helv Helvetica}|) and there has been no +previous call to one of these primitives, then the default map file +\filename{pdftex.map} will \emph{not} be read. Apart from this case, the +given map file will be processed as with the \type{+} modifier: +duplicate later map entries within the file are ignored and a warning is +issued. Thus, you can block reading of the default map file also with an +empty \verb|\pdfmapfile{}| or \verb|\pdfmapline{}| early in the \TeX\ +file. Since the default map file is typically large, if you don't need +it, these command variants might considerably speed up \PDFTEX\ startup. + +If a modifier is given, before reading the items given as arguments to +the present \cs{pdfmapfile} or \cs{pdfmapline}, the default map file +will be read first---if this hasn't already been done or been prevented +by the above blocking cases. The meaning of the modifiers: + +\begin{itemize} +\item \verb|\pdfmapfile{+foo.map}| reads the file \filename{foo.map}; +duplicate later map entries within the file are ignored and a warning is +issued. + +\item \verb|\pdfmapfile{=foo.map}| reads the file \filename{foo.map}; +matching map entries in the database are replaced by new entries from +\filename{foo.map}, if they haven't already been used. + +\item \verb|\pdfmapfile{-foo.map}| reads the file \filename{foo.map}; +matching map entries are deleted from the database, if they haven't +already been used. +\end{itemize} + +In short, if you want to add support for a new font through an +additional font map file while keeping all the existing mappings, use +\verb|\pdfmapfile{+myfont.map}| or \verb|\pdfmapfile{=myfont.map}|. + +If you want to use a base map file name other than \type{pdftex.map}, or +change its processing options through a \PDFTEX\ format, you can do this +by appending the \cs{pdfmapfile} command to the \cs{everyjob} token list +for the \type{-ini} run, as in: + +\begin{verbatim} +\everyjob=\expandafter{\the\everyjob\pdfmapfile{+myspecial.map}} +\dump +\end{verbatim} + +This would always read the file \type{myspecial.map} after the default +\type{pdftex.map} file. + +\subsection{\cs{pdfmapline}} +\pdftexprimitive{\Syntax{\cs{pdfmapline} \Something{map spec}}} + +Similar to \cs{pdfmapfile}, but here you give a single map line (exactly +like the ones in map files) as an argument. The optional modifiers +(\type{+-=}) have the same effect as with \cs{pdfmapfile}; see also the +description above. Example: + +\begin{verbatim} +\pdfmapline{+ptmri8r Times-Italic <8r.enc <ptmri8a.pfb} +\end{verbatim} + +This primitive, especially the \verb|\pdfmapline{=...}| form, is useful +for temporary quick checks of a new font map entry during development, +before finally putting it into a map file. + +As explained above, \verb|\pdfmapline{}|, like \verb|\pdfmapfile{}|, +blocks reading of the default map file, if it comes early enough in the +\TeX\ input. \introduced{1.20a} + +\subsection{\cs{pdfmovechars}} +\pdftexprimitive{\Syntax{\cs{pdfmovechars} \Whatever{integer}}} + +Since \PDFTEX\ version 1.30.0 the primitive \cs{pdfmovechars} is +obsolete, and its use merely leads to a warning. (This primitive +specified whether \PDFTEX\ should try to move characters in range 0..31 +to higher slots; its sole purpose was to remedy certain bugs of early +\PDF\ viewers.) + +\subsection{\cs{pdfnobuiltintounicode}} +\pdftexprimitive{\Syntax{\cs{pdfnobuiltintounicode} \Something{font}}} + +The purpose of this command is to prevent \PDFTEX\ from generating the +\type{ToUnicode}/CMap resource for the given font when +\cs{pdfgentounicode=1}, most likely because the CMap resource is already +generated by some other method. For instance, the \LATEX\ \type{cmap} +package uses \cs{pdffontattr} to generate CMap resources. + +Minimal example: +\begin{verbatim} +\font\f=cmb10 +\pdfnobuiltintounicode\f +\f No unicode mappings for this output. +\end{verbatim} +\introduced{1.40.11} + +\subsection{\cs{pdfnoligatures}} +\pdftexprimitive{\Syntax{\cs{pdfnoligatures} \Something{font}}} + +This disables all ligatures in the loaded font \Something{font}. +\introduced{1.30.0} + +\subsection{\cs{pdfomitcharset}} +\pdftexprimitive{\Syntax{\cs{pdfomitcharset} \Whatever{integer}}} + +If this primitive parameter is zero (the default), the \type{/CharSet} +entry is included as usual for fonts in the \PDF\ output; if it is set +to 1, then \type{/CharSet} is omitted. Other values may have other +meanings in the future, so do not rely on them. + +Explanation: This parameter was created because the \PDFA-1 standard +requires \type{/CharSet}, whereas \PDFA-2 and \PDFA-3 allow it to be +omitted but have extraordinary requirements, which \PDFTEX\ does not +currently meet, if it is included.\introduced{1.40.20} + +\subsection{\cs{pdfpkmode}} +\pdftexprimitive{\Syntax{\cs{pdfpkmode} \Whatever{tokens}}} + +The \cs{pdfpkmode} is a token register that sets the \METAFONT\ mode for +pixel font generation. The contents of this register is dumped into the +format, so one can (optionally) preset it. \introduced{1.30.0} + +\subsection{\cs{pdfpkresolution}} +\pdftexprimitive{\Syntax{\cs{pdfpkresolution} \Whatever{integer}}} + +This integer parameter specifies the default resolution of embedded \PK\ +fonts and is read when \PDFTEX\ embeds a \PK\ font during finishing the +\PDF\ output. As bitmap fonts may be rendered poorly, and in any case +cannot be arbitrarily magnified, it is best to use outline fonts if +possible. + +\subsection{\cs{pdfsuppresswarningdupmap}} +\pdftexprimitive{\Syntax{\cs{pdfsuppresswarningdupmap} \Whatever{integer}}} + +Ordinarily, \PDFTEX\ gives a warning when a duplicate map entry for a +given font is read, whatever the mechanism. However, sometimes it is +useful to include map information within the document, using +\cs{pdfmapfile} or \cs{pdfmapline}, even for fonts that happen to be +installed on the system. Then seeing the warnings on every run is just +noise; it can be suppressed by setting this parameter to a positive +number. \introduced{1.40.13} + +\subsection{\cs{pdftracingfonts}} +\pdftexprimitive{\Syntax{\cs{pdftracingfonts} \Whatever{integer}}} + +This integer parameter specifies the level of verbosity for the +information about expanded fonts given in the log, \eg\ when +\cs{tracingoutput=1}. If \cs{pdftracingfonts=0}, which is the default, +the log shows the actual nonzero signed expansion value for each +expanded letter within brackets, as in: + +\begin{verbatim} +...\xivtt (+20) t +\end{verbatim} + +If \cs{pdftracingfonts=1}, the name of the \TFM\ file is also listed, +together with the font size: + +\begin{verbatim} +...\xivtt (cmtt10+20@14.0pt) t +\end{verbatim} + +Setting \cs{pdftracingfonts} to a value other than~0 or~1 is not +recommended, to allow for future extensions. \introduced{1.30.0} + +\subsection{\cs{pdfuniqueresname}} +\pdftexprimitive{\Syntax{\cs{pdfuniqueresname} \Whatever{integer}}} + +When this primitive is assigned a positive number, \PDF\ resource names +will be made reasonably unique by appending a random string consisting +of six \ASCII\ characters. + +\subsection{\cs{tagcode}} +\pdftexprimitive{\Syntax{\cs{tagcode} \Something{font} + \Something{8-bit number} \Whatever{integer}}} + +This primitive accesses a character's \type{char_tag} info. It is meant +to delete \type{lig_tag} (the character's ligature/kerning program), +\type{list_tag} (which indicates that the character belongs to a chain of +ascending sizes) and/or \type{ext_tag} (which indicates that the character +is extensible), with the following options: assigning \type{-7} or less +clears all tags, \type{-6} clears \type{ext_tag} and \type{list_tag}, +\type{-5} clears \type{ext_tag} and \type{lig_tag}, \type{-4} clears +\type{ext_tag}, \type{-3} clears \type{list_tag} and \type{lig_tag}, +\type{-2} clears \type{list_tag}, \type{-1} clears \type{lig_tag}, +and \type{0} or larger does nothing. Changes are irreversible and global. + +Conversely, when queried, the primitive returns \type{0} if the tag's +value is \type{no_tag}, \type{1} if \type{lig_tag} is set, \type{2} if +\type{list_tag} is set or \type{4} (not~3) if \type{ext_tag} is set. + +\section{Spacing} + +Controlling spacing before and after characters was introduced in +version 1.30, mostly to handle punctuation rules in different +languages. The \cs{...code} tables here, like those in the previous +section, operate globally, \ie\ ignore \TeX's usual grouping, and apply +only to the given \Something{font}, not other instances of the +underlying font. + +\subsection{\cs{pdfadjustinterwordglue}} +\pdftexprimitive{\Syntax{\cs{pdfadjustinterwordglue} \Whatever{integer}}} + +If positive, adjustment of interword glue is enabled and controlled by the +following three primitives. + +\subsection{\cs{knbscode}} +\pdftexprimitive{\Syntax{\cs{knbscode} \Something{font} + \Something{8-bit number} \Whatever{integer}}} + +The amount of space, in thousandths of an em, added to the natural width +of the glue following a character (the name stands for ``kern before +space'', although technically it is looking at glue items, not kern +items). This amounts is clipped to the range $-1000..1000$. For +instance, in the following example, glue after periods in the current +font will be increased by .2em. + +\begin{verbatim} +\pdfadjustinterwordglue=1 +\knsbcode\font`\.=200 +\end{verbatim} + +\subsection{\cs{stbscode}} +\pdftexprimitive{\Syntax{\cs{stbscode} \Something{font} + \Something{8-bit number} \Whatever{integer}}} + +This works like \cs{knbscode}, but applies to the stretch component of +the following glue. + +\subsection{\cs{shbscode}} +\pdftexprimitive{\Syntax{\cs{shbscode} \Something{font} + \Something{8-bit number} \Whatever{integer}}} + +Like \cs{stbscode}, but for the shrink component. + +\subsection{\cs{pdfprependkern}} +\pdftexprimitive{\Syntax{\cs{pdfprependkern} \Whatever{integer}}} + +If positive, automatic insertion of kerns before characters is enabled. + +\subsection{\cs{knbccode}} +\pdftexprimitive{\Syntax{\cs{knbccode} \Something{font} + \Something{8-bit number} \Whatever{integer}}} + +The width of the kern, in thousandths of an em, inserted before a +character. It is clipped to the range $-1000..1000$. For instance, with +the following code, a .15em-kern will be inserted before all question +marks in the current font (possibly useful for \eg\ French punctuation): + +\begin{verbatim} +\pdfprependkern=1 +\knbccode\font`\?=150 +\end{verbatim} + +\subsection{\cs{pdfappendkern}} +\pdftexprimitive{\Syntax{\cs{pdfappendkern} \Whatever{integer}}} + +Same as \cs{pdfprependkern}, but for kerns inserted after characters. + +\subsection{\cs{knaccode}} +\pdftexprimitive{\Syntax{\cs{knaccode} \Something{font} + \Something{8-bit number} \Whatever{integer}}} + +Same as \cs{knbccode}, except the kern is inserted after the +character. Such a kern is required for instance after a left guillemet +in French punctuation. + +\section{Vertical adjustments} + +\subsection{\cs{pdfignoreddimen}} +\pdftexprimitive{\Syntax{\cs{pdfignoreddimen} \Whatever{dimen}}} + +This specifies the dimension value which must be assigned to the +following four primitives so they are ignored. Default is +\type{-1000pt}, and it should be modified with care since it also +influences when a previous paragraph's depth is ignored (for instance, +the plain \TEX\ macro \cs{nointerlineskip} should be modified +accordingly). + +\subsection{\cs{pdffirstlineheight}, \cs{pdflastlinedepth}} +\pdftexprimitive{\Syntax{\cs{pdffirstlineheight} \Whatever{dimen}}} +\pdftexprimitive{\Syntax{\cs{pdflastlinedepth} \Whatever{dimen}}} + +These parameters specify the height of the first, resp.\ depth of the +last, line of a paragraph, regardless of its content. They are read when +the paragraph builder is called, and ignored when set to +\cs{pdfignoreddimen}. By default, they are set to \type{-1000pt}, so +they are ignored as long as the value of \cs{pdfignoreddimen} is not +changed. + +\subsection{\cs{pdfeachlineheight}, \cs{pdfeachlinedepth}} +\pdftexprimitive{\Syntax{\cs{pdfeachlineheight} \Whatever{dimen}}} +\pdftexprimitive{\Syntax{\cs{pdfeachlinedepth} \Whatever{dimen}}} + +\cs{pdfeachlineheight} is similar to \cs{pdffirstlineheight}, but for +all lines of a paragraph, including the first one, unless +\cs{pdffirstlineheight} is specified. + +\cs{pdfeachlinedepth} is the same, but for the depth. + +\section{\PDF\ objects} + +\subsection{\cs{pdfobj}} +\pdftexprimitive{\Syntax{\cs{pdfobj} \Something{object type spec} + \Modelist{h, v, m}}} + +This command creates a raw \PDF\ object that is written to the \PDF\ +file as \verb|1 0 obj| \ldots\ \type{endobj}. + +When \Something{object type spec} is not given, \PDFTEX\ no longer +creates a dictionary object with contents \Something{general text}, as +it did in the past. + +When \Something{object type spec} is given as \Something{attr +spec} \Literal{stream}, the object will be created as a stream with +contents \Something{general text} and additional attributes in +\Something{attr spec}. + +When \Something{object type spec} is given as \Something{attr spec} +\Literal{file}, then the \Something{general text} will be treated as a file +name and its contents will be copied into the stream contents. + +When \Something{object type spec} is given as \type{reserveobjnum}, just +a new object number is reserved. The number of the reserved object is +accessible via \cs{pdflastobj}. The object can later be filled with +contents by \Syntax{\cs{pdfobj} \Literal{useobjnum} \Something{number} +\Lbrace\Something{balanced text}\Rbrace}. But the reserved object number +can be used by other objects before it is defined, which provides a +forward\hyph referencing mechanism. + +The object is kept in memory and will be written to the \PDF\ output only +when its number is referred to by \cs{pdfrefobj} or when \cs{pdfobj} +is preceded by \cs{immediate}. Nothing is appended to the list being +built. The number of the most recently created object is accessible via +\cs{pdflastobj}. + +\subsection{\cs{pdflastobj}} +\pdftexprimitive{\Syntax{\cs{pdflastobj} \Whatever{read-only integer}}} + +This command returns the object number of the last object created by \type +{\pdfobj}. + +\subsection{\cs{pdfrefobj}} +\pdftexprimitive{\Syntax{\cs{pdfrefobj} \Something{object number} + \Modelist{h, v, m}}} + +This command appends a whatsit node to the list being built. When the whatsit +node is searched at shipout time, \PDFTEX\ will write the object +\Something{object number} +to the \PDF\ output if it has not been written yet. + +\subsection{\cs{pdfretval}} +\pdftexprimitive{\Syntax{\cs{pdfretval} \Whatever{read-only integer}}} + +Set to $-1$ if \cs{pdfobj} ignores an invalid object number. Perhaps +this will be used to store the error status of other primitives in the +future. + +\section{Page and pages objects} + +\subsection{\cs{pdfpagesattr}} +\pdftexprimitive{\Syntax{\cs{pdfpagesattr} \Whatever{tokens}}} + +\PDFTEX\ expands this token list when it finishes the \PDF\ output and +adds the resulting character stream to the root \type{Pages} +object. When defined, these are applied to all pages in the +document. Some examples of attributes are \type{/CropBox}, the rectangle +specifying the region of the page being displayed and printed, and +\type{/Rotate}, the number of degrees (in multiples of 90) the page +should be rotated clockwise when it is displayed or printed. + +% /MediaBox is not a good example, since it will never take effect. +\begin{verbatim} +\pdfpagesattr + { /Rotate 90 % rotate all pages by 90 degrees + /CropBox [0 0 612 792] } % the crop size of all pages (in bp) +\end{verbatim} + +\subsection{\cs{pdfpageattr}} +\pdftexprimitive{\Syntax{\cs{pdfpageattr} \Whatever{tokens}}} + +This is similar to \cs{pdfpagesattr}, but has priority over it. +It can be used to override any attribute given by \cs{pdfpagesattr} +for an individual page. The token list is expanded when \PDFTEX\ ships out +a page. The contents are added to the attributes of the current page. + +If the \cs{pdfpageattr} value contains the string \type{/MediaBox}, +then \PDFTEX\ omits outputting its own \type{/MediaBox} value (which is +\verb|[0 0 |\Something{\it page\_width} \Something{\it +page\_height}\type{]}). (This behavior was introduced in version +1.40.18.) + +\subsection{\cs{pdfomitprocset}} +\pdftexprimitive{\Syntax{\cs{pdfomitprocset} \Whatever{integer}}} + +If this parameter is zero (the default), the \type{/ProcSet} array is +included if \cs{pdfmajorversion} is~1, and omitted if +$\cs{pdfmajorversion}\ge2$. If this parameter is $>0$, \type{/ProcSet} +is always omitted; if it is $<0$, \type{/ProcSet} is always +included. For information about what \type{/ProcSet} is, see the +\PDFReference\ or other documentation. + +\cs{ProcSet} was considered obsolete as of \PDF~1.4, but conforming +writers should continue to output it. It was formally deprecated in +\PDF~2.0.\introduced{1.40.25} + +\subsection{\cs{pdfpageref}} +\pdftexprimitive{\Syntax{\cs{pdfpageref} \Something{page number} + \Whatever{expandable}}} + +This primitive expands to the number of the page object that contains +the dictionary for page \Something{page number}. If the page +\Something{page number} does not exist, a warning will be issued, +a fresh unused \PDF\ object will be generated, and \cs{pdfpageref} +will expand to that object number. + +\Eg\ if the dictionary for page~5 of the \TEX\ document is contained in +\PDF\ object no.~18, \cs{pdfpageref5} expands to the number 18. + +\subsection{\cs{pdfpageresources}} +\pdftexprimitive{\Syntax{\cs{pdfpageresources} \Whatever{tokens}}} + +These tokens are added to the resource dictionary for all pages, before +the font, XObject, and ProcSet resources. For example: + +\begin{verbatim} +\pdfpageresources{/MyPageResourceAttribute /MyValue} +\end{verbatim} + +\section{Form XObjects} + +The next three primitives support a \PDF\ feature called ``object +reuse'' in \PDFTEX. The idea is first to create a `form XObject'. The +content of this object corresponds to the content of a \TEX\ box; it can +contain pictures and references to other form XObjects as well. After +creation, the form XObject can be used multiple times by simply +referring to its object number. This feature can be useful for large +documents with many similar elements, to reduce the duplication of +identical objects. + +These commands behave similarly to \cs{pdfobj}, \cs{pdfrefobj} and +\cs{pdflastobj} (described in the previous section), but instead of +taking raw \PDF\ code, they handle text typeset by \TEX. + +\subsection{\cs{pdfxform}} +\pdftexprimitive{\Syntax{\cs{pdfxform} \Optional{\Something{attr spec}} + \Optional{\Something{resources spec}} \Something{box number} + \Modelist{h, v, m}}} + +This command creates a form XObject corresponding to the contents of the +box \Something{box number}. The box can contain other raw objects, form +XObjects, or images as well. However, it cannot contain annotations +because those are laid out on a separate layer, are positioned +absolutely, and have dedicated housekeeping. \cs{pdfxform} makes box +\Something{box number} void, as \cs{box} does. + +When \Something{attr spec} is given, the text will be written +as additional attribute into the form XObject dictionary. The +\Something{resources spec} is similar, but the text will be added +to the resources dictionary of the form XObject. The text given by +\Something{attr spec} or \Something{resources spec} is written before +other entries of the form dictionary and\slash or the resources dictionary +and takes priority over later ones. + +\subsection{\cs{pdfrefxform}} +\pdftexprimitive{\Syntax{\cs{pdfrefxform} \Something{object number} + \Modelist{h, v, m}}} + +The form XObject is kept in memory and will be written to the \PDF\ +output only when its object number is referred to by \cs{pdfrefxform} +or when \cs{pdfxform} is preceded by \cs{immediate}. Nothing is +appended to the list being built. The number of the most recently created +form XObject is accessible via \cs{pdflastxform}. + +When issued, \cs{pdfrefxform} appends a whatsit node to the list being +built. When the whatsit node is searched at shipout time, \PDFTEX\ will +write the form \Something{object number} to the \PDF\ output if it is +not written yet. + +\subsection{\cs{pdflastxform}} +\pdftexprimitive{\Syntax{\cs{pdflastxform} \Whatever{read-only integer}}} + +The object number of the most recently created form XObject is accessible +via \cs{pdflastxform}. + +As said, this feature can be used for reusing information. This mechanism +also plays a role in typesetting fill\hyph in forms. Such widgets sometimes +have visuals that show up on user request, but are hidden otherwise. + +\subsection{\cs{pdfxformname}} +\pdftexprimitive{\Syntax{\cs{pdfxformname} \Something{object number} + \Whatever{expandable}}} + +In \PDF\ files produced by \PDFTEX\ one can recognize a form XObject by +the prefix~\type{/Fm} followed by a number, for instance \type{/Fm2}. +For a given form XObject number, this primitive expands to the number in +the corresponding form XObject name. \Eg\ if \type{/Fm2} corresponds to +some form XObject with object number 7, the \cs{pdfxformname7} +expands to the number~\type{2}. \introduced{1.30.0} + +\section{Graphics inclusion} + +\PDF\ provides a mechanism for embedding graphic and textual objects: +form XObjects. In \PDFTEX\ this mechanism is accessed by means of +\cs{pdfxform}, \cs{pdflastxform} and \cs{pdfrefxform} (described in the +previous section). A special kind of XObjects are bitmap graphics and +for manipulating them similar commands are provided. + +\subsection{\cs{pdfximage}} +\pdftexprimitive{\Syntax{\cs{pdfximage} + \Optional{\Something{rule spec}} + \Optional{\Something{attr spec}} + \Optional{\Something{page spec}} + \Optional{\Something{pdf box spec}} + \Optional{\Something{colorspace spec}} + \Next + \Something{general text} + \Modelist{h, v, m} +}} + +This command creates an image object from the filename given in +\Something{general text}, \ie\ enclosed in braces. + +The image is kept in memory when this command is executed. It is written +to the \PDF\ output only when either 1)~the \cs{pdfximage} command is +preceded by \cs{immediate}, or 2)~its number is referred to by +\cs{pdfrefximage} (q.v.). + +The dimensions of the image can be controlled via \Something{rule spec}. +The default values are zero for depth and ``running'' for height and +width. If all of them are given, the image will be scaled to fit the +specified values. If some (but not all) are given, the rest will be set +to a value corresponding to the remaining ones so as to make the image +size to yield the same proportion of $width : (height+depth)$ as the +original image size, where depth is treated as zero. If none are given +then the image will have its natural size. + +An image inserted at its natural size often has a resolution of +\type{\pdfimageresolution} (see below) given in dots per inch in the +output file, but some images may contain data specifying the image +resolution, and in such a case the image will be scaled accordingly. The +dimensions of an image can be accessed by putting the \cs{pdfrefximage} +command in a box and checking the box's dimensions: + +\begin{verbatim} +\setbox0=\hbox{\pdfximage{somefile.png}\pdfrefximage\pdflastximage} +\end{verbatim} + +Now we can use \cs{wd0} and \cs{ht0} to find the natural size of the +image as determined by \PDFTEX. + +The image type is specified by the extension of the given file name: +\type{.png} stands for \PNG\ image, \type{.jpg} (or \type{.jpeg}) for +\JPEG, \type{.jbig2} (preferred, but \type{.jb2} works also) for +\JBIGTWO, and \type{.pdf} for \PDF\ file. But once \PDFTEX\ has opened +the file, it checks the file type first by checking the magic number at +the file start, which gets precedence over the file name extension. This +gives a certain degree of fault tolerance, if the file name extension is +stated wrongly. + +Similarly to \cs{pdfxform}, the optional text given by \Something{attr +spec} will be written as additional attributes of the image before other +keys of the image dictionary. When using this, be aware that slightly +different types of \PDF\ objects are created while including \PNG, +\JPEG, or \JBIG2\ bitmaps and \PDF\ images. + +While working with \PDF\ or \JBIG2\ images, \Something{page spec} allows +to specify which page of the document is to be included; the +\Something{page spec} is irrelevant for the other two image formats. + +Starting with \PDFTEX\ 1.11, in the \PDF\ image case, you may also +choose which page box of the image is to be treated as a final bounding +box. If \Something{pdf box spec} is present, it overrides the default +behavior specified by the \cs{pdfpagebox} parameter, and is overridden +by the (obsolete) \cs{pdfforcepagebox} parameter. This option is +irrelevant for non\hyph \PDF\ inclusions. + +Starting with \PDFTEX\ 1.21, \cs{pdfximage} supports a \type{colorspace} +keyword followed by an object number (user\hyph defined colorspace for +the image being included). This feature works for \JPEG\ images only. +\PNG\ images use \RGB\ palettes, \JBIG2 bi-tonal, and \PDF\ images have +self\hyph contained color space information. + +\subsection{\cs{pdfrefximage}} +\pdftexprimitive{\Syntax{\cs{pdfrefximage} \Something{object number}}} + +\cs{pdfrefximage} appends a whatsit node to the list being built. When +the whatsit node is searched at shipout time, \PDFTEX\ will write the image +with number \Something{object number} to the \PDF\ output if it has not been +written yet. + +\subsection{\cs{pdflastximage}} +\pdftexprimitive{\Syntax{\cs{pdflastximage} \Whatever{read-only integer}}} + +\type{\pdflastximage} is the number of the most recently created XObject +image. + +\subsection{\cs{pdfximagebbox}} +\pdftexprimitive{\Syntax{\cs{pdfximagebbox} \Something{integer} + \Something{integer} \Whatever{expandable}}} + +The dimensions of the bounding box of a \PDF\ image loaded with +\cs{pdfximage} are stored in a table. This primitive returns those +dimensions as follows: + +\begin{verbatim} +\pdfximage{afile.pdf} +\pdfximagebbox\pdflastximage 1 % Returns lower-left x +\pdfximagebbox\pdflastximage 2 % Returns lower-left y +\pdfximagebbox\pdflastximage 3 % Returns upper-right x +\pdfximagebbox\pdflastximage 4 % Returns upper-right y +\end{verbatim} + +\subsection{\cs{pdflastximagecolordepth}} +\pdftexprimitive{\Syntax{\cs{pdflastximagecolordepth} + \Whatever{read-only integer}}} + +The color depth (\type{1} for 1-bit images, \type{2} for 2-bit images, +and so on) of the last image accessed with \cs{pdfximage}. + +\subsection{\cs{pdflastximagepages}} +\pdftexprimitive{\Syntax{\cs{pdflastximagepages} + \Whatever{read-only integer}}} + +This read-only register returns the highest page number from a file +previously accessed via the \cs{pdfximage} command. +This is useful only for \PDF\ files; it always returns \type{1} +for \PNG, \JPEG, or \JBIGTWO\ files. + +\subsection{\cs{pdfimageresolution}} +\pdftexprimitive{\Syntax{\cs{pdfimageresolution} \Whatever{integer}}} + +The integer \cs{pdfimageresolution} parameter (given in dots per inch, +dpi) is a last resort value, used only for bitmap (\JPEG, \PNG, +\JBIGTWO) images, but not for \PDF{}s. The priorities are as follows: +Often one image dimension (\type{width} or \type{height}) is stated +explicitly in the \TEX\ file. Then the image is properly scaled so that +the aspect ratio is kept. If both image dimensions are given, the image +will be stretched accordingly, whereby the aspect ratio might get +distorted. If no image dimensions are given in the \TEX\ file, the image +size will be calculated from its width and height in pixels, using the +$x$ and $y$ resolution values normally contained in the image file. If +one of these resolution values is missing or weird (either $<$~0 or +$>$~65535), the \cs{pdfimageresolution} value will be used for both $x$ +and $y$ resolution when calculating the image size. And if the +\cs{pdfimageresolution} is zero, a final fallback resolution of 72dpi is +used. + +The \cs{pdfimageresolution} is read when \PDFTEX\ creates an image via +\cs{pdfximage}. The given value is clipped to the range $0..65535$ +(dpi). + +Currently this parameter is used particularly for calculating the +dimensions of \JPEG\ images with \EXIF\ information (unless at least one +dimension is stated explicitly); the resolution values included in +\EXIF\ data are ignored. + +\subsection{\cs{pdfpagebox}} +\pdftexprimitive{\Syntax{\cs{pdfpagebox} \Whatever{integer}}} + +When \PDF\ files are included, the command \cs{pdfximage} allows the +selection of which \PDF\ page box to use in the optional +\Something{image attr spec}. If the option isn't present, the page box +defaults to the value of \cs{pdfpagebox} as follows: (1)~media box, +(2)~crop box, (3)~bleed box, (4)~trim box, and (5)~artbox. + +\subsection{\cs{pdfforcepagebox}} +\pdftexprimitive{\Syntax{\cs{pdfforcepagebox} \Whatever{integer}}} + +%- It is now possible to specify the pdf page box to use when including pdfs. +% The syntax has been extended: +% \pdfximage [<image attr spec>] <general text> (h, v, m) +% <image attr spec> --> [<rule spec>] [<attr spec>] [<page spec>] [<pdf box spec>] +% <pdf box spec> --> mediabox|cropbox|bleedbox|trimbox|artbox +% The default is cropbox (which defaults to mediabox), to be compatible with +% previous versions of pdfTeX. +% The page box specified at \pdfximage can be globally overridden with the +% config parameter always_use_pdfpagebox and the command +% \pdfoptionalwaysusepdfpagebox <integer>, where 0 is the default (use +% whatever is specified with \pdfximage), 1 is media, 2 is crop, 3 is +% bleed, 4 is trim and 5 is artbox. This can only be set once per +% object, i.e., the value used at \pdfximage is remembered. +% See the PDF Reference for an explanation of the boxes. + +The integer primitive \cs{pdfforcepagebox} allows globally overriding +the choice of the page box used with \cs{pdfximage}. It takes the same +values as \cs{pdfpagebox}. The command is available starting with +\PDFTEX\ 1.30.0, as a shortened synonym of obsolete +\cs{pdfoptionalwaysusepdfpagebox} instruction, but is itself now +considered obsolete---a combination of \cs{pdfpagebox} and +\Something{image attr spec} is better. + +\subsection{\cs{pdfinclusionerrorlevel}} +\pdftexprimitive{\Syntax{\cs{pdfinclusionerrorlevel} \Whatever{integer}}} + +This controls the behavior of \PDFTEX\ when a \PDF\ file is included +which has a newer \PDF\ version than the one specified by +\cs{pdfmajorversion} and \cs{pdfminorversion}. If +\cs{pdfinclusionerrorlevel} is set to~0 (the default), \PDFTEX\ gives a +warning; if 1, \PDFTEX\ raises an error; if negative, no diagnostic at +all is given. + +It was originally a shortened synonym of +\cs{pdfoptionpdfinclusionerrorlevel}, which is now obsolete. +\introduced{1.30.0} + +\subsection{\cs{pdfimagehicolor}} +\pdftexprimitive{\Syntax{\cs{pdfimagehicolor} \Whatever{integer}}} + +This parameter, when set to~1, enables embedding of \PNG\ images with +16~bit wide color channels at their full color resolution. This +embedding mode is defined only from \PDF\ version~1.5 onwards, so the +\cs{pdfimagehicolor} functionality is automatically disabled in \PDFTEX\ +if $\cs{pdfminorversion}<5$ and $\cs{pdfmajorversion}=1$; in this case, +each 16~bit color channel is reduced to a width of 8~bits by stripping +the lower 8~bits before embedding. The same stripping happens when +\cs{pdfimagehicolor} is set to~0. If $\cs{pdfmajorversion}=1$ and +$\cs{pdfminorversion}\ge5$, or $\cs{pdfmajorversion}\ge2$, the default +value of \cs{pdfimagehicolor} is~1. + +If specified, the parameter must appear before any data is written to +the \PDF\ output. \introduced{1.30.0} + +\subsection{\cs{pdfimageapplygamma}} +\pdftexprimitive{\Syntax{\cs{pdfimageapplygamma} \Whatever{integer}}} + +This primitive, when set to~1, enables gamma correction while embedding +\PNG\ images, taking the value of the primitive \cs{pdfgamma} as +well as the gamma value embedded in the \PNG\ image into account. When +\cs{pdfimageapplygamma} is set to~0, no gamma correction is +performed. + +If specified, the parameter must appear before any data is written to +the \PDF\ output. \introduced{1.30.0} + +\subsection{\cs{pdfgamma}} +\pdftexprimitive{\Syntax{\cs{pdfgamma} \Whatever{integer}}} + +This primitive defines the `device gamma' for \PDFTEX. Values are in +promilles (same as \cs{mag}). The default value of this primitive +is~1000, defining a device gamma value of~1.0. + +If \cs{pdfimageapplygamma} is set to~1, then whenever a \PNG\ image is +included, \PDFTEX\ applies a gamma correction. This correction is based +on the value of the \cs{pdfgamma} primitive and the `assumed device +gamma' that is derived from the value embedded in the actual image. If +no embedded value can be found in the \PNG\ image, then the value of +\cs{pdfimagegamma} is used instead. + +If specified, the parameter must appear before any data is written to +the \PDF\ output. \introduced{1.30.0} + +\subsection{\cs{pdfimagegamma}} +\pdftexprimitive{\Syntax{\cs{pdfimagegamma} \Whatever{integer}}} + +This primitive gives a default `assumed gamma' value for \PNG\ images. +Values are in promilles (same as for \cs{pdfamma}). The default value +of this primitive is~2200, implying an assumed gamma value of~2.2. + +When \PDFTEX\ is applying gamma corrections, images that do not have an +embedded `assumed gamma' value are assumed to have been created for a +device with a gamma of 2.2. Experiments show that this default setting +is correct for a large number of images; however, if your images come +out too dark, you probably want to set \cs{pdfimagegamma} to a lower +value, like~1000. + +If specified, the parameter must appear before any data is written to +the \PDF\ output. \introduced{1.30.0} + +\subsection{\cs{pdfpxdimen}} +\pdftexprimitive{\Syntax{\cs{pdfpxdimen} \Whatever{dimen}}} + +While working with bitmap graphics or typesetting electronic documents, +it might be convenient to base dimensions on pixels rather than \TeX's +standard units like \type{pt} or \type{em}. For this purpose, \PDFTEX\ +provides an extra unit named \type{px} that takes the dimension given to +the \cs{pdfpxdimen} primitive. For example, to make the unit \type{px} +corresponding to 96dpi pixel density (then $\mbox{1px}=72/96$bp), one +can do the following calculation: + +\begin{verbatim} +\pdfpxdimen=1in % 1 dpi +\divide\pdfpxdimen by 96 % 96 dpi +\hsize=1200px +\end{verbatim} + +Then \cs{hsize} amounts to 1200~pixels in 96dpi, which is exactly +903.375pt, which \TeX\ rounds to 903.36914pt. + +The default value of \cs{pdfpxdimen} is 1.00001bp (for historical +reasons), corresponding to a pixel density of (a few sp off from) 72dpi. +The \LUATEX\ default is 1bp (also a few sp off from 72dpi), so to get +precisely the same behavior in \PDFTEX\ and \LUATEX, set +\cs{pdfpxdimen}\texttt{=1bp}. + +This primitive is completely independent of the +\cs{pdfimageresolution} and \cs{pdfpkresolution} parameters. + +\introduced{1.30.0} It used to be an integer register that gave the +dimension 1px as number of scaled points, defaulting to 65536 (1px equal +to $\mbox{65536sp}=1$pt). Starting with \PDFTEX\ 1.40.0, \cs{pdfpxdimen} +is now a real dimension parameter. + +\subsection{\cs{pdfinclusioncopyfonts}} +\pdftexprimitive{\Syntax{\cs{pdfinclusioncopyfonts} \Whatever{integer}}} + +If positive, this parameter tells \PDFTEX\ to include fonts that are +embedded in a \PDF\ file loaded with \cs{pdfximage}, even if those fonts +are also available on disk. Bigger files might be created, but included +\PDF\ files are sure to be embedded with the correct fonts; indeed, the +fonts on disk might be different from the embedded ones, and glyphs +might be missing. + +\subsection{\cs{pdfsuppresswarningpagegroup}} +\pdftexprimitive{\Syntax{\cs{pdfsuppresswarningpagegroup} + \Whatever{integer}}} + +Ordinarily, \PDFTEX\ gives a warning when more than one included \PDF\ +file has a so-called ``page group object'' (\type{/Group}), because only +one can ``win''---that is, be propagated to the page level. Usually +the page groups are identical, but when they are not, the result is +unpredictable. It would be ideal if \PDFTEX\ in fact detected whether +the page groups were the same and only gave the warning in the +problematic case; unfortunately, this is not easy (a patch would be +welcome). Nevertheless, often one observes that there is no actual +problem. Then seeing the warnings on every run is just noise, and can +be suppressed by setting this parameter to a positive number. +\introduced{1.40.15} + +\section{Annotations} + +\PDF\ 1.4 provides four basic kinds of annotations: + +\begin{itemize} +\item hyperlinks, general navigation +\item text clips (notes) +\item movies +\item sound fragments +\end{itemize} + +The first type differs from the other three in that there is a +designated area involved on which one can click, or when moved over some +action occurs. \PDFTEX\ is able to calculate this area, as we will see +later. All annotations can be supported using the next two general +annotation primitives. + +\subsection{\cs{pdfannot}} +\pdftexprimitive{\Syntax{\cs{pdfannot} \Something{annot type spec} + \Modelist{h, v, m}}} + +This command appends a whatsit node corresponding to an annotation to +the list being built. The dimensions of the annotation can be controlled +via the \Something{rule spec}. The default values are ``running'' for +all width, height and depth. When an annotation is written out, running +dimensions will take the corresponding values from the box containing +the whatsit node representing the annotation. The \Something{general +text} is inserted as raw \PDF\ code to the contents of annotation. The +annotation is written only if the corresponding whatsit node is searched +at shipout time. + +\subsection{\cs{pdflastannot}} +\pdftexprimitive{\Syntax{\cs{pdflastannot} \Whatever{read-only integer}}} + +This primitive returns the object number of the last annotation created by +\cs{pdfannot}. These two primitives allow users to create any annotation +that cannot be created by \cs{pdfstartlink} (see below). + +\section{Destinations and links} +\label{sec.linking} + +The first type of annotation (hyperlinks and navigation), mentioned +above, is implemented by three primitives. The first one is used to +define a specific location as being referred to. This location is tied +to the page, not the exact location on the page. The main reason for +this is that \PDFTEX\ maintains a dedicated list of these annotations, +and more when optimized, for the sole purpose of speed. + +\subsection{\cs{pdfdest}} +\pdftexprimitive{\Syntax{\cs{pdfdest} \Something{dest spec} + \Modelist{h, v, m}}} + +This primitive appends a whatsit node which establishes a destination +for links and bookmark outlines; the link is identified by either a +number or a symbolic name, and the way the viewer is to display the page +is specified in \Something{dest spec}, which must be one of those +mentioned in the table below. + +\begin{smalltable} +\begin{tabular}{ll} +\bf keyword & \bf meaning \cr +\tt fit & fit the page in the window \cr +\tt fith & fit the width of the page \cr +\tt fitv & fit the height of the page \cr +\tt fitb & fit the \type{BoundingBox} of the page \cr +\tt fitbh & fit the width of \type{BoundingBox} of the page \cr +\tt fitbv & fit the height of \type{BoundingBox} of the page \cr +\tt fitr \Something{\rm rule spec} + & fit according to \Something{\rm rule spec} \cr +\tt xyz \Optional{zoom \Something{\rm number}} + & goto the current position (see below) \cr +\tt struct \Optional{\Something{\rm number}} + & create structure destination (see below) \cr +\end{tabular} +\end{smalltable} + +The \Literal{xyz} keyword can optionally be followed by \Literal{zoom} +\Something{integer} to provide a fixed zoom\hyph in. The +\Something{integer} is used like the \TEX\ magnification value, \ie\ +1000 is the normal page view. When \Literal{zoom} \Something{integer} is +given, the zoom factor changes to 0.001 of the \Something{integer} +value, otherwise the current zoom factor is kept unchanged. + +If \Literal{struct} \Something{number} is used, a structure destination +is created instead of a regular destination, referring to the structure +element defined in object \Something{number}. Structure destinations use +a separate namespace and therefore may have the same identifiers as a +regular destination. + +The destination is written out only if the corresponding whatsit node is +searched at shipout time. + +\subsection{\cs{pdfstartlink}} +\pdftexprimitive{\Syntax{\cs{pdfstartlink} + \Optional{\Something{rule spec}} + \Optional{\Something{attr spec}} + \Something{action spec} + \Modelist{h, m} +}} + +This primitive is used along with \cs{pdfendlink} and appends +a whatsit node corresponding to the start of a hyperlink. The whatsit +node representing the end of the hyperlink is created by +\cs{pdfendlink}. The dimensions of the link are handled in the +similar way as in \cs{pdfannot}. Both \cs{pdfstartlink} and +\cs{pdfendlink} must be in the same level of box nesting. A hyperlink +with running width can be multi\hyph line or even multi\hyph page, in which case +all horizontal boxes with the same nesting level as the boxes containing +\cs{pdfstartlink} and \cs{pdfendlink} will be treated as part of +the hyperlink. The hyperlink is written out only if the corresponding +whatsit node is searched at shipout time. + +Additional attributes, which are explained in great detail in the +\PDFReference, can be given via \Something{attr spec}. Typically, the +attributes specify the color and thickness of any border around the +link. As a simple example, \verb|/C [0.9 0 0] /Border [0 0 2]| specifies +a color (in \RGB) of dark red, and a border thickness of 2~points. + +While all graphics and text in a \PDF\ document have relative positions, +annotations have internally hard\hyph coded absolute positions. Again +this is for the sake of speed optimization. The main disadvantage is +that these annotations do \emph{not} obey transformations issued by +\type{\pdfliteral}. + +The \Something{action spec} specifies the action that should be +performed when the hyperlink is activated, one of (see the syntax +rules): \Literal{user} \Something{user-action spec}, +\Literal{goto} \Something{goto-action spec}, +\Literal{thread} \Something{thread-action spec}. + +\begin{itemize} +\item A \Something{user-action spec} (\type{user{...}}) performs a +user\hyph defined action. Examples: +a \URL, as in \verb|/S /URI /URI (https://tug.org/)|; +a named action, as in \verb|/S /Named /N /NextPage|. + +\item A \Something{goto-action spec} (\type{goto...}) performs various +goto actions, and is by far the most complex action. Here is a copy of +the syntax, for easier reference: + +\Syntax{\small +\Something{goto-action spec} \Means % + \Optional{\Something{goto-action struct spec}} \Something{numid} + \Or \Next \Optional{\Something{file spec}} \Optional{\Something{goto-action struct spec}} \Something{nameid} + \Or \Next \Optional{\Something{file spec}} \Optional{\Something{goto-action struct spec}} \Optional{\Something{page spec}} \Something{general text} + \Or \Next \Something{file spec} \Optional{\Something{goto-action struct spec}} \Something{nameid} \Something{newwindow spec} + \Or \Next \Something{file spec} \Optional{\Something{goto-action struct spec}} \Optional{\Something{page spec}} \Something{general text} \Something{newwindow spec} +} + +\begin{itemize} +\item The \Something {numid} and \Something{nameid} alternatives specify a +destination identifier. + +\item The \Something{page spec} alternative specifies a page number for the +destination. In this case, the zoom factor is given by +\Something{general text}. + +\item The default behavior of \Something{newwindow spec} depends on the +browser setting. + +\item A destination in another \PDF\ file can be given with +\Something{file spec}, in which case \Something{newwindow spec} +specifies whether the file should be opened in a new window. A +\Something{file spec} can be either a \type{(}\Something{string}\type{)} +or a \type{<<}\Something{dictionary}\type{>>}. + +\item If a \Something{goto-action spec} contains a +\Something{goto-action struct spec}, then a structure destination is +referenced in addition to the regular destination. The form with +\Something{general text} is used if and only if a \Something{file spec} +is present; then the \Something{general text} should expand to a literal +\PDF\ dictionary describing a structure destination. Otherwise, the +\Something{numid} or \Something{nameid} directly after the +\Literal{struct} keyword identify a destination which must have been +created with \cs{pdfdest} \Literal{struct}\unskip. + +\end{itemize} + +\item A \Something{thread-action spec} (\type{thread...}) performs +article thread reading. The thread identifier, \Something{numid} or +\Something{nameid}, is similar to the destination identifier. A thread +in another \PDF\ file can be referenced by specifying a \Something{file +spec}. + +\end{itemize} + +\subsection{\cs{pdfendlink}} +\pdftexprimitive{\Syntax{\cs{pdfendlink} \Modelist{h, m}}} + +This primitive ends a link started with \cs{pdfstartlink}. All text +between \cs{pdfstartlink} and \cs{pdfendlink} will be treated as part +of this link. \PDFTEX\ may break the result across lines (or pages), in which +case it will make several links with the same content. + +\subsection{\cs{pdflastlink}} +\pdftexprimitive{\Syntax{\cs{pdflastlink} \Whatever{read-only integer}}} + +This primitive returns the object number of the last link created by +\cs{pdfstartlink} (analogous to \cs{pdflastannot}). +\introduced{1.40.0} + +\subsection{\cs{pdflinkmargin}} +\pdftexprimitive{\Syntax{\cs{pdflinkmargin} \Whatever{dimen}}} + +This dimension parameter specifies the margin of the box representing +a hyperlink and is read when a page containing hyperlinks is shipped out. + +\subsection{\cs{pdfdestmargin}} +\pdftexprimitive{\Syntax{\cs{pdfdestmargin} \Whatever{dimen}}} + +Margin added to the dimensions of the rectangle around the destinations. + +\subsection{\cs{pdfsuppresswarningdupdest}} +\pdftexprimitive{\Syntax{\cs{pdfsuppresswarningdupdest} \Whatever{integer}}} + +Ordinarily, \PDFTEX\ gives a warning when the same destination is used +more than once. However, due to problematic macro packages, sometimes a +document may end up producing the warning through no fault of its own, +and fixing the macros may not be feasible. Then seeing the warnings on +every run is just noise, and can be suppressed by setting this parameter +to a positive number. \introduced{1.40.13} + +\subsection{\cs{pdfrunninglinkon}, \cs{pdfrunninglinkoff}} +\pdftexprimitive{\Syntax{\cs{pdfrunninglinkoff}}} +\pdftexprimitive{\Syntax{\cs{pdfrunninglinkon}}} + +These commands create corresponding whatsit nodes which turn off/on +generation of running links. Their typical usage is to turn off +generation of running links in the header or footer of a page. +Generation of running links is on when the shipout routine begins. + +The generation of running links works roughly like this: \PDFTEX\ keeps +a stack of links created by \cs{pdfstartlink}, called +\type{pdf_link_stack}. When writing out an hbox to \PDF, \PDFTEX\ checks +if the nesting level of the box is the same as the nesting level of the +top entry in \type{pdf_link_stack}; if so, that box would become a link, +too. + +The whatsit nodes created by the above primitives turn off/on a flag +which controls if a hbox being shipped can become a link, in addition to +the previous condition. + +Thus, the commands must be inserted before the hbox in question. For example: + +\begin{verbatim} +% (1) good: +\hbox{\pdfrunninglinkoff + \hbox{text that would become a link otherwise} +} + +% (2) bad: +\hbox{\pdfrunninglinkoff text that would become a link otherwise} +% too late; \pdfrunninglinkoff must be inserted before the box +\end{verbatim} + +\section{Bookmarks} + +\subsection{\cs{pdfoutline}} +\pdftexprimitive{\Syntax{\cs{pdfoutline} + \Optional{\Something{attr spec}} + \Something{action spec} + \Optional{\Literal{count} \Something{integer}} + \Something{general text} + \Modelist{h, v, m} +}} + +This primitive creates an outline (or bookmark) entry. The first +parameter, \Something{attr spec}, specifies the action to be taken, and +is the same as that allowed for \type{\pdfstartlink}. + +The \Literal{count} \Something{integer} specifies the number of direct +subentries under this entry; specify~0 or omit the clause if this entry +has no subentries. If the \Something{integer} is negative, then all +subentries will be closed and the absolute value of this number +specifies the number of subentries. + +The \Something{general text} is what will be shown in the outline +window. The outline is written to the \PDF\ output immediately. + +\section{Article threads} + +\subsection{\cs{pdfthread}} +\pdftexprimitive{\Syntax{\cs{pdfthread} \Optional{\Something{rule spec}} + \Optional{\Something{attr spec}} \Something{id spec} \Modelist{h, v, m}}} + +Defines a bead within an article thread. Thread beads with same +identifiers (spread across the document) will be joined together. + +\subsection{\cs{pdfstartthread}} +\pdftexprimitive{\Syntax{\cs{pdftstartthread} + \Optional{\Something{rule spec}} + \Optional{\Something{attr spec}} + \Something{id spec} \Modelist{v, m}}} + +This uses the same syntax as \cs{pdfthread}, apart that it must be +followed by a \cs{pdfendthread}. \cs{pdfstartthread} and the +corresponding \cs{pdfendthread} must end up in vboxes with the same +nesting level; all vboxes between them will be added into the thread. + +In the output routine, if there are other newly created boxes which have +the same nesting level as the vbox(es) containing \cs{pdfstartthread} +and \cs{pdfendthread}, they will be also added into the thread, which is +probably not what you want. To avoid such undesired behavior, it's often +enough to wrap boxes that shouldn't belong to the thread by a box to +change their box nesting level. + +\subsection{\cs{pdfendthread}} +\pdftexprimitive{\Syntax{\cs{pdfendthread} \Modelist{v, m}}} + +This ends an article thread started before by \cs{pdfstartthread}. + +\subsection{\cs{pdfthreadmargin}} +\pdftexprimitive{\Syntax{\cs{pdfthreadmargin} \Whatever{dimen}}} + +Specifies a margin to be added to the dimensions of a bead within +an article thread. + +\section{Literals and specials} + +\subsection{\cs{pdfliteral}} +\pdftexprimitive{\Syntax{\cs{pdfliteral} + \Optional{\Literal{shipout}} + \Optional{\Literal{direct} \Or \Literal{page}} + \Something{general text} + \Modelist{h, v, m} + }} + +Analogous to \cs{special} in the original \TEX, this command inserts +raw \PDF\ code into the output, appending a whatsit node to the list +being built. This allows support of color and text transformation, among +other things. + +By default, \Something{general text} is expanded immediately, when the +whatsit node is created, as with \cs{special}. Starting with \PDFTEX\ +1.40.25, the optional keyword \Literal{shipout} can be used to delay +expansion of \Something{general text} until the whatsit node is shipped +out, as with non-\cs{immediate} \cs{write}. + +Normally, \PDFTEX\ ends a text section in the \PDF\ output and sets the +transformation matrix to the current location on the page before +inserting \Something{general text}; this can be turned off by +giving the optional keyword \Literal{direct}. + +Starting with version 1.30.0, \PDFTEX\ supports the keyword \type{page} +in addition to \type{direct}. Both modify the default behavior of +\cs{pdfliteral}, avoiding translation of the coordinate space before +inserting the literal code. The difference is that the \type{page} +keyword instructs \PDFTEX\ to close a \type{BT...ET} text block before +inserting anything. This means that the literal code inserted refers to +the \PDF\ origin (lower-left corner of the page) and can be safely +enclosed with \type{q...Q}. In contrast, using \type{q...Q} operators +inside \cs{pdfliteral} with the \type{direct} keyword will produce +corrupted \PDF\ output, as the \PDF\ standard doesn't allow doing +anything like this within a \type{BT...ET} block. + +\subsection{\cs{special}} +\pdftexprimitive{\Syntax{\cs{special} \Lbrace\Literal{pdf:} + \Something{text}\Rbrace}} + +This is equivalent to \Syntax{\cs{pdfliteral} +\Lbrace\Something{text}\Rbrace}. + +\subsection{\cs{special\ direct}} +\pdftexprimitive{\Syntax{\cs{special} \Lbrace\Literal{pdf:direct:} + \Something{text}\Rbrace}} + +This is equivalent to \Syntax{\cs{pdfliteral} \Literal{direct} +\Lbrace\Something{text}\Rbrace}. + +\subsection{\cs{special\ page}} +\pdftexprimitive{\Syntax{\cs{special} \Lbrace\Literal{pdf:page:} + \Something{text}\Rbrace}} + +This is equivalent to \Syntax{\cs{pdfliteral} \Literal{page} +\Lbrace\Something{text}\Rbrace}. + +\subsection{\cs{special\ shipout}} +\pdftexprimitive{\Syntax{\cs{special} \Optional{\Literal{shipout}} + \Lbrace\Something{text}\Rbrace}} + +Starting with version 1.40.25, \PDFTEX\ extends the \cs{special} +primitive to support the optional keyword \Literal{shipout}. This delays +expansion of \Something{text} until the page is shipped out, as with +non-\cs{immediate} \cs{write}. By default, \Something{text} is expanded +immediately. + +\Syntax{\cs{special} \Literal{shipout} \Lbrace \Literal{pdf:} +\Something{text}\Rbrace} is equivalent to \Syntax{\cs{pdfliteral} +\Literal{shipout} \Lbrace \Something{text}\Rbrace}. + +\section{Strings} + +\subsection{\cs{pdfescapestring}} +\pdftexprimitive{\Syntax{\cs{pdfescapestring} \Something{general text} + \Whatever{expandable}}} + +Starting with version 1.30.0, \PDFTEX\ provides a mechanism for +converting a general text into \PDF\ string. Many characters that may be +needed inside such a text (notably parentheses), have a special meaning +inside a \PDF\ string object and thus, can't be used literally. The +primitive replaces each special \PDF\ character by its literal +representation by inserting a backslash before that character. Some +characters (\eg\ space) are also converted into 3\hyph digit octal +number. For example, \verb|\pdfescapestring{Text (1)}| will be expanded +to \type{Text\040\(1\)}. This ensures a literal interpretation of the +text by the \PDF\ viewer. \introduced{1.30.0} + +\subsection{\cs{pdfescapename}} +\pdftexprimitive{\Syntax{\cs{pdfescapename} \Something{general text} + \Whatever{expandable}}} + +Analogous to \cs{pdfescapestring}, \cs{pdfescapename} replaces each +special \PDF\ character inside the general text by its hexadecimal +representation preceded by a \type{#} character. This ensures the proper +interpretation of the text if used as a \PDF\ name object. In example, +\verb|Text (1)| will be replaced by \type{Text#20#281#29}. +\introduced{1.30.0} + +\subsection{\cs{pdfescapehex}} +\pdftexprimitive{\Syntax{\cs{pdfescapehex} \Something{general text} + \Whatever{expandable}}} + +This command converts each character of \Something{general text} into its +hexadecimal representation. Each character of the argument becomes a pair of +hexadecimal digits. \introduced{1.30.0} + +\subsection{\cs{pdfunescapehex}} +\pdftexprimitive{\Syntax{\cs{pdfunescapehex} \Something{general text} + \Whatever{expandable}}} + +This command treats each character pair of \Something{general text} as +a hexadecimal number and returns the corresponding characters. +\introduced{1.30.0} + +\subsection{\cs{pdfstrcmp}} +\pdftexprimitive{\Syntax{\cs{pdfstrcmp} \Something{general text} + \Something{general text} \Whatever{expandable}}} + +This command compares two strings and expands to \type{0} if the strings +are equal, to \type{-1} if the first string ranks before the second, and +to \type{1} otherwise. \introduced{1.30.0} + +\subsection{\cs{pdfmatch}} +\pdftexprimitive{\Syntax{\cs{pdfmatch} \Optional{\Literal{icase}} + \Optional{\Literal{subcount} \Something{integer}} \Something{general text} + \Something{general text} \Whatever{expandable}}} + +This command implements pattern matching, using \POSIX\ extended regular +expression syntax. The first \Something{general text} is a pattern and +the second is a string. The command expands to \type{-1} if the pattern +is invalid, to \type{0} if no match is found, and to \type{1} if a match +is found. With the \type{icase} option, the matching is +case-insensitive. The \type{subcount} option sets the size of the table +storing the found (sub)patterns; its default is 10. \introduced{1.30.0} + +\subsection{\cs{pdflastmatch}} +\pdftexprimitive{\Syntax{\cs{pdflastmatch} \Something{integer} + \Whatever{expandable}}} + +The matches found with \cs{pdfmatch} are stored in a table. This command +returns the entry for match \Something{integer}, in the format +\Something{position}\type{->}\Something{string}; \Something{position} is +the position of the match (starting at zero) or \type{-1} if no match +was found, and \Something{string} is the matched substring. + +Entry~0 contains the match as a whole; the subsequent entries contain +submatches corresponding to the subpatterns, up to \type{subcount-1}. + +If \Something{integer} is less than zero, an error is given. + +For instance: + +\begin{verbatim} +\pdfmatch subcount 3 {ab(cd)*ef(gh)(ij)}{abefghij} +\pdflastmatch0 % "0->abefghij" +\pdflastmatch1 % "-1->" +\pdflastmatch2 % "4->gh" +\pdflastmatch3 % "-1->" +\end{verbatim} + +Entry~1 is empty because no match was found for \type{cd}, and entry~3 +is empty because it exceeds the table's size as set by \type{subcount}. +\introduced{1.30.0} + +\section{Numbers} + +\subsection{\cs{ifpdfabsnum}, \cs{ifpdfabsdim}} +\pdftexprimitive{\Syntax{\cs{ifpdfabsnum} \Whatever{expandable}}} +\pdftexprimitive{\Syntax{\cs{ifpdfabsdim} \Whatever{expandable}}} + +This conditional works like the standard \cs{ifnum} (resp.\ \cs{ifdim}), +except that it compares absolute values of numbers (dimensions). +Although it seems to be a trivial shortcut for a couple of regular +\cs{if} tests, as primitives they are considerably simpler and faster to +use. \introduced{1.40.0} + +\subsection{\cs{pdfnormaldeviate}} +\pdftexprimitive{\Syntax{\cs{pdfnormaldeviate} \Whatever{expandable}}} + +Generate a normally-distributed random integer with a mean of~0 and +standard deviation 65536. That is, about 68\% of the time, the result +will be between $-65536$ and $65536$ (one standard deviation away from +the mean). About 95\% of results will be within two standard deviations, +and 99.7\% within three. This primitive expands to a list of tokens. +\introduced{1.30.0} + +\subsection{\cs{pdfuniformdeviate}} +\pdftexprimitive{\Syntax{\cs{pdfuniformdeviate} \Something{number} + \Whatever{expandable}}} + +Generate a uniformly-distributed random integer value between 0 +(inclusive) and \Something{number} (exclusive). This primitive expands +to a list of tokens. \introduced{1.30.0} + +\subsection{\cs{pdfrandomseed}} +\pdftexprimitive{\Syntax{\cs{pdfrandomseed} \Whatever{read-only integer}}} + +You can use \cs{pdfrandomseed} to query the current seed value, so you +can \eg\ write the value to the log file. The initial value of the seed +is derived from the system time, and is not more than 1\,000\,999\,999 +(this ensures that the value can be used with commands like \cs{count}). +\introduced{1.30.0} + +\subsection{\cs{pdfsetrandomseed}} +\pdftexprimitive{\Syntax{\cs{pdfsetrandomseed} \Something{number}}} + +Set the random seed (\cs{pdfrandomseed}) to a specific value, +allowing you to replay sequences of semi-randoms at a later moment. +\introduced{1.30.0} + +\section{Timekeeping} + +\subsection{\cs{pdfelapsedtime}} +\pdftexprimitive{\Syntax{\cs{pdfelapsedtime} \Whatever{read-only integer}}} + +Return a number that represents the time elapsed from the moment of the +start of the run. The elapsed time is returned in `scaled seconds', +meaning seconds divided by 65536, \eg\ \PDFTEX\ has run for +\the\pdfelapsedtime\ `scaled seconds' when this paragraph was typeset. +The primitive will never return a value greater than the highest number +available in \TeX: if the time exceeds 32767 seconds, the constant value +$2^{31}-1$ will be returned. \introduced{1.30.0} + +\subsection{\cs{pdfresettimer}} +\pdftexprimitive{\Syntax{\cs{pdfresettimer}}} + +Reset the internal timer so that \cs{pdfelapsedtime} +starts returning the scaled seconds from~0 again. \introduced{1.30.0} + +\section{Files} + +\subsection{\cs{pdffiledump}} +\pdftexprimitive{\Syntax{\cs{pdffiledump} + \Optional{\Literal{offset} \Something{integer}} + \Optional{\Literal{length} \Something{integer}} + \Something{general text} \Whatever{expandable}}} + +Expands to the dump of the first \type{length} \Something{integer} bytes +of the file specified by \Something{general text}, in uppercase +hexadecimal format (same as \cs{pdfescapehex}), starting at offset +\type{offset}~\Something{number}, or the beginning of the file if +\type{offset} is zero or not specified. If \type{length} is not given, +the default is zero, so expands to nothing. Both \Something{integer}s +must be $\ge0$. For example, the first ten bytes of the source of this +manual are {\tt\pdffiledump length 10 {./\jobname}}. +\introduced{1.30.0} + +\subsection{\cs{pdffilesize}} +\pdftexprimitive{\Syntax{\cs{pdffilesize} \Something{general text} + \Whatever{expandable}}} + +Expands to the size of the file specified by \Something{general text}, +\eg\ {\tt \pdffilesize{./\jobname}} for the source of this manual. +\introduced{1.30.0} + +\subsection{\cs{pdfmdfivesum\ file}} +\pdftexprimitive{\Syntax{\cs{pdfmdfivesum} + \Optional{\Literal{file}} + \Something{general text} \Whatever{expandable}}} + +If the keyword \type{file} is given, expands to the \MDFIVE\ checksum of +the \Something{general text} in uppercase hexadecimal format (same as +\cs{pdfescapehex}). Without \type{file}, expands to the \MDFIVE\ of the +\Something{general text} taken as a string. For example, the \MDFIVE\ of +the source for this manual is {\tt \pdfmdfivesum file{./\jobname}}. +\introduced{1.30.0} + +\subsection{\cs{pdffilemoddate}} +\pdftexprimitive{\Syntax{\cs{pdffilemoddate} \Something{general text} + \Whatever{expandable}}} + +Expands to the modification date of file specified by \Something{general +text}, in the same format as for \cs{pdfcreationdate}, \eg\ {\tt +\pdffilemoddate {./\jobname}} for the source of this manual. As of +\PDFTEX\ 1.40.20, if the \type{SOURCE_DATE_EPOCH} and +\type{FORCE_SOURCE_DATE} environment variables are both set, +\cs{pdffilemoddate} returns a value in UTC, ending in \type{Z}. +\introduced{1.30.0} + +\subsection{\cs{input}} +\pdftexprimitive{\Syntax{\cs{input} \Something{general text} + \Whatever{expandable}}} + +As of \TEXLIVE\ 2020, the \cs{input} primitive in all \TEX\ engines, +including \PDFTEX, now also accepts a group-delimited filename argument, +as a system-dependent extension, as in +\cs{input}\Lbrace\type{foo.tex}\Rbrace. The standard usage of \cs{input} +with a space/token-delimited filename is completely unchanged. + +This group-delimited argument was previously implemented in Lua\TEX; now +it is available in all engines. \ASCII\ double quote characters +(\type{"}) are removed from the filename, but it is otherwise left +unchanged after tokenization. + +This extension is unlike most others in that it affects a primitive in +standard \TEX\ (\cs{input}), rather than being related to a new +primitive, command line option, etc. This is allowed because additional +methods of recognizing filenames are explicitly mentioned in +\type{tex.web} as acceptable system-dependent extensions. + +Incidentally, this does not directly affect \LATEX's \cs{input} +command, as that is a macro redefinition of the standard \cs{input} +primitive. + +\introduced{1.40.21} + +\section{Color stack} + +\PDFTEX\ 1.40.0 introduced color stack support; more generally, stacks +of any graphic state. + +\subsection{\cs{pdfcolorstackinit}} +\pdftexprimitive{\Syntax{\cs{pdfcolorstackinit} \Optional{\Literal{page}} + \Optional{\Literal{direct}} \Something{general text} \Whatever{expandable}}} + +The primitive initializes a new graphic stack and returns its number. +The optional \Literal{page} keyword instructs \PDFTEX\ to restore the +graphic at the beginning of every new page. The optional +\Literal{direct} keyword has the same effect as for \cs{pdfliteral} +primitive. \introduced{1.40.0} + +\subsection{\cs{pdfcolorstack}} +\pdftexprimitive{\Syntax{\cs{pdfcolorstack} \Something{stack number} + \Something{stack action} \Something{general text}}} +\noindent \Something{stack action} \Means + \Literal{set} \Or \Literal{push} \Or \Literal{pop} \Or \Literal{current} + +The command operates on the stack of a given \Something{stack number}. +If \Something{stack action} is: + +\begin{description} +\item[\Literal{push}:] the new value in \Something{general text} is inserted at +the top of the graphic stack and becomes the current stack value. + +\item[\Literal{pop}:] the top value is removed from the stack and the new +top value becomes the top of the stack. + +\item[\Literal{set}:] the current value is replaced with +\Something{general text}, without changing the stack size. + +\item[\Literal{current}:] the current stack value is return without +modifying the stack. +\end{description} + +\introduced{1.40.0} + +\section{Transformations} + +Since the content of \cs{pdfliteral} is not interpreted, any +transformation inserted directly into the content stream, as well as +saving and restoring the current transformation matrix, will be +unnoticed by \PDFTEX's positioning mechanism. As a consequence, links +and other annotations (that are formed in \PDF\ on a different layer +then the page content) are not affected by such user-defined +transformations. \PDFTEX\ 1.40.0 solves this problem with three new +primitives. + +\subsection{\cs{pdfsetmatrix}} +\pdftexprimitive{\Syntax{\cs{pdfsetmatrix}}} + +Affine transformations are normally expressed with six numbers. The +first four (no unit) values defining scaling, rotating and skewing, plus +two extra dimensions for translation (shifting). Since translation is +handled by \TeX\ itself, the \cs{pdfsetmatrix} primitive expects as an +argument a string containing just the first four numbers of the +transformation separated by a space and assumes the two position +coordinates to be~0. + +For example, \verb|\pdfsetmatrix{0.87 -0.5 0.5 0.87}| rotates the +current space by 30 degrees, inserting +\verb|0.87 -0.5 0.5 0.87 0 0 cm| into the output. \introduced{1.40.0} + +\subsection{\cs{pdfsave}} +\pdftexprimitive{\Syntax{\cs{pdfsave}}} + +The command saves the current transformation by inserting the \type{q} +operator into the content stream. \introduced{1.40.0} + +\subsection{\cs{pdfrestore}} +\pdftexprimitive{\Syntax{\cs{pdfrestore}}} + +The command restores previously saved transformation by inserting the +\type{Q} operator into the content stream. \cs{pdfsave} and +\cs{pdfrestore} pairs should always be properly nested and should start +and end at the same group level. \introduced{1.40.0} + +\section{Macro programming} + +Expansion-related commands. + +\subsection{\cs{expanded}} +\pdftexprimitive{\Syntax{\cs{expanded} \Something{tokens} + \Whatever{expandable}}} + +Expands \Something{tokens} in exactly the same way as \cs{message}. In +contrast to \cs{edef}, macro parameter characters do not need to be +doubled. \cs{protected} macros (q.v.) are not expanded. +\introduced{1.40.20} + +\subsection{\cs{ifincsname}} +\pdftexprimitive{\Syntax{\cs{ifincsname} \Whatever{expandable}}} + +This conditional is true if evaluated inside \cs{csname} \ldots +\cs{endcsname}, and false otherwise. + +\subsection{\cs{ifpdfprimitive}} +\pdftexprimitive{\Syntax{\cs{ifpdfprimitive} \Something{control sequence} + \Whatever{expandable}}} + +This conditional checks if the following control sequence has its +primitive meaning. If so, \cs{ifpdfprimitive} is true. In any other case +(redefined, made \cs{undefined}, has never been primitive), it is false. +\introduced{1.40.0} + +\subsection{\cs{partokencontext}} +\pdftexprimitive{\Syntax{\cs{partokencontext} \Something{number}}} + +The \varname{par-token} (\ie\ the token with the name given by +\cs{partokenname}, which is \cs{par} by default; see \cs{partokenname}, +next) is inserted into the input stream in different places, according +to the \cs{partokencontext} value. This value can be: + +0 (the default): {\em par-token} is inserted at empty lines (more + exactly, when a token category~5 is seen in state~$N$, reading a + line); before \cs{end}, \cs{vskip}, \cs{hrule}, \cs{unvbox}, and + \cs{halign}, if \TeX{} is in horizontal mode when those commands are + seen; and in various error recovery situations. These are the + standard cases in \TeX. + +1: {\em par-token} is inserted as above, and also at the end of + \cs{vbox}, \cs{vtop}, and \cs{vcenter}, if \TeX{} is in + horizontal mode at the time. + +2: {\em par-token} is inserted as above, and also at the end of + \cs{insert}, \cs{vadjust}, \cs{output}, \cs{noalign}, and + items of \cs{valign}, again if \TeX{} is in horizontal mode at the + time. + +With the default \cs{partokencontext=0}, \TEX\ behaves in its normal +way: the situations in cases 1 and 2 are processed by a direct call of +{\em end-paragraph} routine, with no emitted {\em par-token}. + +If \cs{partokencontext=1} then \TeX\ inserts the {\em par-token} in +additional cases: when vertical boxes are completed but horizontal mode +is not finished. Since vboxes are not uncommonly inserted directly by +users, with horizontal mode material, this allows macro programmers to +control all such boxes being finished by a {\em par-token}. An example: + +\begin{verbatim} +\partokenname\_mypar +\partokencontext=1 +\def\_mypar{Hi there!\endgraf} +\vbox{Vbox text.} +\end{verbatim} + +This will output ``Hi there!''\ after ``Vbox text.''. + +Finally, with \cs{partokencontext=2}, all cases where classical \TeX\ +uses the direct {\em end-paragraph} routine are changed to emit the {\em +par-token} instead. In contrast to case~1, these commands are rarely +invoked directly by users with horizontal mode material. + +The setting of the register \cs{partokencontext} is local. + +\introduced{1.40.24} + +\subsection{\cs{partokenname}} +\pdftexprimitive{\Syntax{\cs{partokenname} \Something{control sequence}}} + +\TeX{} internally inserts a control sequence, named \cs{par} by +default, into the input stream at empty lines, the end of vboxes, and +various other places (see \cs{partokencontext}, above). Let's call this +control sequence the \varname{par-token}. + +Executing \cs{partokenname}\Something{control sequence} changes the +name of the \varname{par-token} from \cs{par} to the given +\Something{control sequence}. The setting performed by +\cs{partokenname} is global. + +This makes it possible to release the name \cs{par} to the ``user's name +space'', \ie\ after using \cs{partokenname}, users can define and use +\cs{par} as they wish without changing the behavior of anything internal +to \TeX{}. For example: + +\begin{verbatim} +\catcode`\_=11 +\partokenname\_mypar % use \_mypar at user level +\let\_mypar=\par % make \_mypar equivalent to built-in \par +% +\def\par{some random text} % redefine \par +% +Hello world. + +Goodbye. +\end +\end{verbatim} + +This will not output ``\verb|some random text|'' (the definition of +\cs{par}), due to the \cs{partokenname} setting. + +By default, the meaning of the \varname{par-token} is to end a paragraph +(also named as \cs{endgraf} in the plain \TEX\ format). It can be +changed as usual with, for example, \cs{def}. Naturally, it is the +control sequence name given to \cs{partokenname} that must be +redefined. Continuing the previous example (prior to the \cs{end}): + +\begin{verbatim} +\def\_mypar{Hi there!\endgraf} +Paragraph one. + +Paragraph two.\let\_mypar=\endgraf +\end{verbatim} + +This will output ``Hi there!''\ after ``Paragraph one.'', before ending +the paragraph. + +Another behavior of the \varname{par-token} built into \TEX\ is that +macros not defined as \cs{long} cause the error ``runaway argument'' if +the \varname{par-token} is scanned as a parameter. After +\cs{setpartokenname}, it will be the new control sequence name that +triggers this error, not \cs{par}. For instance (still continuing the +same example): + +\begin{verbatim} +\def\amac#1{} +\amac{long test, no error: \par} +\amac{long test, gives error: \_mypar} +\end{verbatim} + +\introduced{1.40.24} + +\subsection{\cs{pdfprimitive}} +\pdftexprimitive{\Syntax{\cs{pdfprimitive} \Something{control sequence}}} + +This command executes the primitive meaning of the following control +sequence, regardless of whether the control sequence has been redefined +or made undefined. If the primitive was expandable, \cs{pdfprimitive} +expands also. On the other hand, if the following control sequence never +was a primitive, nothing happens and no error is raised. (In some +versions of \PDFTEX\ prior to 1.40.19, an error was wrongly given.) +\introduced{1.40.0} + +\section{Typesetting} + +\subsection{\cs{pdfinsertht}} +\pdftexprimitive{\Syntax{\cs{pdfinsertht} \Something{integer} + \Whatever{expandable}}} + +If \Something{integer} is the number of an insertion class, this command +returns the current height of the corresponding box. For instance, the +following returns \type{12pt} in plain \TEX: + +\begin{verbatim} +Abc\footnote*{Whatever.}\par +\pdfinsertht\footins +\end{verbatim} + +\subsection{\cs{pdflastxpos}, \cs{pdflastypos}} +\pdftexprimitive{\Syntax{\cs{pdflastxpos} \Whatever{read-only integer}}} +\pdftexprimitive{\Syntax{\cs{pdflastypos} \Whatever{read-only integer}}} + +This primitive returns an integer number representing the absolute $x$ +resp.\ $y$ coordinate of the last point marked by \cs{pdfsavepos}. The +unit is scaled points (sp). + +\subsection{\cs{pdfsavepos}} +\pdftexprimitive{\Syntax{\cs{pdfsavepos} \Modelist{h, v, m}}} + +This primitive marks the current absolute ($x,y$) position on the media, +with the reference point in the lower left corner. It is active only +during page shipout, when the final page is assembled. The position +coordinates can then be retrieved by the \cs{pdflastxpos} and +\cs{pdflastypos} primitives, and \eg\ written out to some auxiliary +file. The coordinates can be used only after the current \cs{shipout} +has been finalized, therefore normally two \PDFTEX\ runs are required to +utilize these primitives. Starting with \PDFTEX\ 1.40.0, this mechanism +can also be used while running in \DVI\ mode. + +\subsection{\cs{quitvmode}} +\pdftexprimitive{\Syntax{\cs{quitvmode}}} + +The primitive instructs \PDFTEX\ to quit vertical mode and start +typesetting a paragraph. Thus, \cs{quitvmode} has the same basic effect +as the \cs{leavevmode} macro from \type{plain.tex}. However, +\cs{leavevmode} expands the \cs{everypar} token list, which may or may +not be desired. \cs{quitvmode} does not expand \cs{everypar}. +\introduced{1.21a} + +\subsection{\cs{vadjust}} +\pdftexprimitive{\Syntax{\cs{vadjust} + \Optional{\Something{pre spec}} + \Something{filler} + \Lbrace \Something{vertical mode material} \Rbrace + \Modelist{h, m} +}} + +In \PDFTEX, the \cs{vadjust} primitive supports an additional optional +qualifier \Something{pre spec}, which is simply the string \type{pre}, +to the original \TEX. If no \type{pre} is given, \cs{vadjust} behaves +exactly as the original (see {\em The \TEX book}, p.~281): it appends an +adjustment item created from \Something{vertical mode material} to the +current list {\em after} the line in which \cs{vadjust} appears. In +contrast, with the qualifier \type{pre}, the adjustment item is put {\em +before} the line in which \cs{vadjust pre} appears. + +\section{Tracing} + +\subsection{\cs{showstream}} +\pdftexprimitive{\Syntax{\cs{showstream} \Whatever{integer}}} + +If this primitive parameter has a value corresponding to an open output +stream (which has been opened with \cs{openout}), then any \cs{show}, +\cs{showthe}, \cs{showbox} or \cs{showlists} commands do not write +output to the terminal, but instead write only to the referenced output +stream, as if they were written with \cs{immediate}\cs{write}. + +For example: +\begin{verbatim} +\newwrite\myoutstream +\immediate\openout\myoutstream="infofile" +\showstream=\myoutstream +% From now on, \show... commands are redirected to "infofile.tex". +\show\TeX +% +\showstream=-1 +% -1 is never a open file and therefore restores +% normal \show... behavior. +\immediate\closeout\myoutstream +\end{verbatim} + +This example would not generate any special output to the terminal or +log file (except for any logging done by \cs{newwrite}. It writes +this text to \type{infofile.tex}, including the initial blank line, +since that is what \cs{show} does: + +\begin{verbatim} + +> \TeX=macro: +->T\kern -.1667em\lower .5ex\hbox {E}\kern -.125emX +\end{verbatim} + +This primitive is available, with identical behavior, in all \TeX\ +engines except the original \TEX\ and \eTeX, where \cs{showstream} +remains undefined. \introduced{1.40.24} + +\subsection{\cs{tracinglostchars}} +\pdftexprimitive{\Syntax{\cs{tracinglostchars} \Whatever{integer}}} + +This primitive parameter has always been part of \TEX, and its operation +with values $\le2$ is unchanged. In addition, if its value is +$\ge3$, then ``Missing character'' reports become full errors +(ordinarily they are only logged), and the character code is reported in +hex. For example: + +\begin{verbatim} +\tracinglostchars=3 +\font\x=logo10 \x \char99 \end +\end{verbatim} + +\noindent will result in this error message: + +\begin{verbatim} +! Missing character: There is no c ("63) in font logo10. +\end{verbatim} + +\noindent (The \type{logo10} font only defines the capital letters used +in the \METAFONT\ and \METAPOST\ logos, so there is no lowercase.) + +This new behavior is essentially the same in all \TeX\ engines except +the original \TEX\ and \eTeX, where the behavior of +\cs{tracinglostchars} remains unchanged. + +\introduced{1.40.22} + +\subsection{\cs{tracingstacklevels}} +\pdftexprimitive{\Syntax{\cs{tracingstacklevels} \Whatever{integer}}} + +If this primitive parameter is $>0$, and $\cs{tracingmacros}>0$, macro +expansion logging is truncated at the specified depth. Also, and more +importantly, each relevant log line is given a prefix beginning with +\type{~}, either followed by a \type{.} character for each expansion +level or another \type{~} if the expansion was truncated. For example: + +\begin{verbatim} +\tracingmacros=1 % so macro expansion is logged at all +\tracingstacklevels=2 % cut off at level 2 +\def\a#1{\relax} % argument to show parameter logging is affected too +\def\b#1{\a{#1}} +\b1 +\end{verbatim} + +\noindent logs the following: + +\begin{verbatim} +~.\b #1->\a {#1} +#1<-1 +~~\a +\end{verbatim} + +Thus, the expansion of \cs{b} is logged normally, with the addition +of the \type{~.} prefix. The expansion of \cs{a} is truncated +(level~2), hence neither the parameters nor body expansion are shown. + +Furthermore, an \cs{input} file counts as an expansion level, and the +input filename is logged. So, if we add this to our example above: +\begin{verbatim} +\input anotherfile +\end{verbatim} + +\noindent where \type{anotherfile.tex} simply contains \cs{b2}, the log +will get: + +\begin{verbatim} +~.INPUT anotherfile.tex +~~\b +~~\a +\end{verbatim} + +Now the \cs{b} expansion is not logged either, since the expansion +depth is higher than the \cs{tracingstacklevels} value. + +The intended use of \cs{tracingstacklevels} is not so much to truncate +logging as to indicate expansion levels for detailed debugging. Thus +normally it would be set to a large number (\cs{maxdimen}), so that +everything is fully logged, with the addition of the expansion level +indication with the number of dots in the prefix. + +This primitive is available, with identical behavior, in all \TeX\ +engines except the original \TEX\ and \eTeX, where +\cs{tracingstacklevels} remains undefined. \introduced{1.40.22} + +\section{\PDFTEX\ execution environment} + +\subsection{\cs{pdfdraftmode}} +\pdftexprimitive{\Syntax{\cs{pdfdraftmode} \Whatever{integer}}} + +When set to 1 (or set by the command-line switch \type{-draftmode}), +\PDFTEX\ doesn't write the output \PDF\ file and doesn't read any +images, but does do everything else (including writing auxiliary files), +thus speeding up compilations when you know you need an extra run but +don't care about the output, \eg\ just to get cross-references started. +If specified, the parameter must appear before any data is written to +the \PDF\ output. \introduced{1.40.0} + +\subsection{\cs{pdfshellescape}} +\pdftexprimitive{\Syntax{\cs{pdfshellescape} \Whatever{read-only integer}}} + +This primitive is~1 if \cs{write18} is enabled, 2 if its operation is +restricted to known-safe programs, and 0 otherwise. \introduced{1.30.0} + +\subsection{\cs{pdftexbanner}} +\pdftexprimitive{\Syntax{\cs{pdftexbanner} \Whatever{expandable}}} + +Returns the \PDFTEX\ banner message, \eg\ for the version used here: +{\tt \pdftexbanner}. \introduced{1.20a} + +\subsection{\cs{pdftexrevision}} +\pdftexprimitive{\Syntax{\cs{pdftexrevision} \Whatever{expandable}}} + +Returns the revision number of \PDFTEX, \eg\ for \PDFTEX\ version +\currentpdftex\ (used to produce this document), it returns the number +{\tt \pdftexrevision}. + +\subsection{\cs{pdftexversion}} +\pdftexprimitive{\Syntax{\cs{pdftexversion} \Whatever{read-only integer}}} + +Returns the version of \PDFTEX\ multiplied by 100, excluding the tertiary +version number, \eg\ for \PDFTEX\ version \currentpdftex\ (used to +produce this document), it returns {\tt \number\pdftexversion}. + +\chapter{Graphics} + +\PDFTEX\ supports inclusion of pictures in \PNG, \JPEG, \JBIGTWO, and +\PDF\ format; a few differences between these are discussed below. The +most common technique with \TEX, the inclusion of \EPS\ figures, is not +(and cannot be) supported; \PDF\ inclusion is usually the easiest +replacement. \EPS\ files can be converted to \PDF\ by \GHOSTSCRIPT, +Adobe Distiller or other \POSTSCRIPT\hyph to\hyph \PDF\ converters. + +\PDFTEX\ allows inserting selected pages from \PDF\ files, carry their +own fonts, graphics, and pixel images, into a document. The cover page +of this manual is an example of such an insert, being a one-page +document generated by \PDFTEX. + +By default \PDFTEX\ takes the BoundingBox of a \PDF\ file from its +CropBox if available, otherwise from its MediaBox. This can be +influenced by the \Something{pdf box spec} option to the \cs{pdfximage} +primitive, or by setting the \cs{pdfpagebox} or \cs{pdfforcepagebox} +primitives to a value corresponding to the desired box type. + +To get the right BoundingBox from a \EPS\ file, before converting to +\PDF, it is necessary to transform the \EPS\ file so that the start +point is at the (0,0)~coordinate and the page size is set exactly +corresponding to the BoundingBox. A \PERL\ script (\EPSTOPDF) for this +purpose and the \PSTOPDF\ program that comes with \GHOSTSCRIPT\ can do a +similar job. (Concerning this conversion, they can handle complete +directories, remove some garbage from files, takes precautions against +duplicate conversion, etc.) + +The lossless compressing \PNG\ format is useful for embedding crisp +pixel graphics (\eg\ line scans, screenshots). As of \PDFTEX\ 1.30.0, +the alpha channel of \PNG\ images is processed if available; this allows +embedding of images with simple transparency. The \PNG\ format does not +support the CMYK color model, which is sometimes required for print +media (this often can be replaced by four component \JPEG\ in high +quality or lossless compression mode). Photos in \PNG\ format have +rather poor compression; here the \JPEG\ format is preferable. + +Embedding \PNG\ images in the general case requires \PDFTEX\ to +uncompress the pixel array and to re\hyph compress it to the \PDF\ +requirements; this may take a noticeable amount of time. Since \PDFTEX\ +1.30.0 there is now a fast \PNG\ embedding mode that goes without +uncompressing; the image data are directly copied into the \PDF\ stream, +resulting in a much higher embedding speed. This direct mode is only +activated if the image array structure of the \PNG\ file is compatible +with the \PDF\ image structure; \eg\ an interlaced \PNG\ image requires +uncompressing to re\hyph arrange the image lines. Luckily, it seems that +in practice \PNG\ files commonly allow fast copying. The use of gamma +correction disables fast copying, as it requires calculations with +individual pixels. Whether the fast copy mode is used for a \PNG\ image +can be seen from the log file, which then shows the string `(PNG copy)' +after the \PNG\ file name. + +The \JPEG\ format is normally used in lossy mode; then it's ideal for +embedding photos. It's not recommended for crisp images from synthetic +sources with a limited amount of colors. Both \JFIF\ and \EXIF\ are +supported for additional information. + +The \JBIGTWO\ format works only for bi-tonal (black and white) pixel +images like scanned line and text documents, but for these it has +typically a much higher compression ratio than the other two pixel image +formats. The \JBIGTWO\ format is part of the \PDF\ standard since +version 1.5; native \JBIGTWO\ image inclusion is available in \PDFTEX\ +since version 1.40.0. A \JBIGTWO\ file might contain many images, which +gives an even better compression ratio than with a single image per +file, as \JBIGTWO\ encoders can exploit similarities between bit +patterns over several images. Encoders for \JBIGTWO\ can operate in +lossy as well as lossless modes. A free \JBIGTWO\ encoder is available: +see \useurl{jbigenc} (perhaps there are others). + +Other options for graphics in \PDFTEX\ are: + +\begin{description} +\item[\LATEX\ picture mode] Since this is implemented simply in terms +of font characters, it works in exactly the same way as usual. + +\item[Xy-pic] If the \POSTSCRIPT\ backend is not requested, Xy-pic +uses its own Type~1 fonts, and needs no special attention. + +\item[tpic] The tpic \cs{special} commands (used in some +macro packages) can be redefined to produce literal \PDF, using some macros +written by Hans Hagen. + +\item[\METAPOST] Although the output of \METAPOST\ is +\POSTSCRIPT, it is in a highly simplified form, and a \METAPOST\ to +\PDF\ conversion (\MPTOPDF, available as \type{supp-pdf.tex} and +\type{supp-pdf.mkii}, written by Hans Hagen and Tanmoy Bhattacharya) is +implemented as a set of macros which reads \METAPOST\ output and +supports all of its features. + +\end{description} + +The inclusion of raw \POSTSCRIPT\ commands, a technique utilized by for +instance the \type{pstricks} package, cannot directly be supported. +Although \PDF\ is a direct descendant of \POSTSCRIPT, it lacks any +programming language commands, and cannot deal with arbitrary +\POSTSCRIPT. + +\chapter{Additional \PDF\ keys} +\label{sec.addpdfkeys} + +{\em This section is based on the manual on keys written by Martin Schr\"oder.} + +A \PDF\ document should contain only the structures and attributes defined +in the \PDF\ specification. However, the specification allows applications +to insert additional keys, provided they follow certain rules. + +The most important rule is that developers have to register with Adobe +prefixes for the keys they want to insert. Hans Hagen has registered the +prefix \type{PTEX} for \PDFTEX. + +\PDFTEX\ generates an XObject for every included \PDF\ image. The dictionary of +this object contains these additional keys: + +\begin{smalltable} +\begin{tabular}{lll} +\bf key & \bf type & meaning \cr +\tt PTEX.FileName & string & The name of the included file as seen by + \PDFTEX. \cr +\tt PTEX.InfoDict & dictionary & The \type{InfoDict} + of the included \PDF\ (an indirect + object). \cr +\tt PTEX.PageNumber & integer & The page number of the included file. \cr +\end{tabular} +\end{smalltable} + +The \PDFReference\ says: ``Although viewer applications can +store custom metadata in the document information dictionary, it is +inappropriate to store private content or structural information there; +such information should be stored in the document catalog instead.'' + +Although it would seem more natural to put this information in the +document information dictionary, we have to obey the rules laid down in +the \PDFReference. The following key ends up in the document catalog. + +\begin{smalltable} +\begin{tabular}{llp{.66\hsize}} +\bf key & \bf type & meaning \cr +\tt PTEX.Fullbanner & string & The full version of the \PDFTEX\ + binary that produced the file as displayed by {\tt pdftex + \type{--version}}, a.k.a.\ \cs{pdftexbanner} ({\tt\pdftexbanner}). + This is necessary because the string in the \type{Producer} key in + the info dictionary is rather short, namely {\tt + pdfTeX-\currentpdftex}. \cr +\end{tabular} +\end{smalltable} + +Any or all of these keys can be suppressed with the +\cs{pdfsuppressptexinfo} primitive, described in +section~\ref{sec.docinfocatalog}. + +\chapter{Character translation} + +Characters that are input to \PDFTEX\ are subject to optional \TEX\ +character translation (\TCX) under control of a \TCX\ file. The \TCX\ +maps the input character codes (\eg\ from \cs{input} or \cs{read}) to +the character codes as seen by \PDFTEX. This mapping takes place before +the characters enter \PDFTEX's `mouth'. If no \TCX\ file is read, the +input characters enter \PDFTEX\ directly; no mapping is done. + +\TCX\ files consist of lines each containing one or two integer numbers +in the range 0..255, either in decimal or hex notation. A comment sign +\type{%} in a \TCX\ line starts a comment until the end of line. The +first number in each line is for matching the input character code, the +second, optional number is the corresponding \TEX\ character code. If a +line contains only one number, characters with this code enter \PDFTEX\ +unchanged; no mapping is done. + +\TCX\ mapping also influences \PDFTEX\ output streams for \cs{message} +and \cs{write}. Without \TCX\ mapping, only characters that are within +the range 32..126 are flagged as `printable', meaning that these +characters are output directly by \cs{message} and \cs{write} +primitives. Characters outside the range 32..126 are instead output in +escaped form, \eg\ as \type{^^A} for a character with code \type{0x01}. +When a character code is mentioned in the 2nd column of the \TCX\ file, +or as the only value in a line, it is flagged as `printable'. During +\cs{message} and \cs{write}, output characters are mapped in reverse +direction: they are looked up in the 2nd column of the \TCX\ file and +the corresponding values from the 1st column are output. Again, if a +\PDFTEX\ character code is found as the only number in a line, no +mapping is done. Mentioning a character code as the only number on a +line has the sole purpose to flag this code `printable'. + +The characters output into the \PDF\ file, \eg\ by the \cs{pdfliteral} +or \cs{special} primitives, are not subject to \TCX\ output remapping. + +Beware: Character translation interferes with the \ENCTEX\ primitives; to +avoid surprises, don't use \ENCTEX\ and \TCX\ mapping at the same time. +Further details about \TCX\ file loading can be found in the \WEBC\ +manual, \useurl{tcxfiles}. + +Nowadays \TCX\ files are rarely used. The \type{-8bit} command line +option makes all characters printable, when that is desired. + +\appendix + +\chapter{Installation} + +This section describes the steps needed to get \PDFTEX\ running on a +system where \PDFTEX\ is not yet installed. Nowadays all known \TEX\ +distributions, such as \TEXLIVE, \MIKTEX, and \MACTEX, include \PDFTEX\ +already. For example, the \TEXLIVE\ distribution comes with \PDFTEX\ +versions for many \UNIX, \WIN, and Mac systems; more information +can be found at \hbox{\useurl{texlive}.} When you use any of these +distributions, you don't need to bother with the \PDFTEX\ installation +procedure in this chapter. + +If there is no precompiled \PDFTEX\ binary for your system, or the +version coming with a distribution is not the current one and you would +like to try out a fresh \PDFTEX\ immediately, you will need to build +\PDFTEX\ from sources; read on. You should already have a working \TEX\ +system, \eg\ \TEXLIVE, into which the freshly compiled \PDFTEX\ will be +integrated. (Numerous support files are required in order to have a +working binary.) Note that the installation description in this manual +is \WEBC\hyph specific. + +\section{Getting sources and binaries} + +The primary home page is \useurl{ptexorg}, where you also find bug +tracking information. Development sources are at \useurl{ptexdevel}. +Precompiled binaries for some platforms are available in subdirectories +below \useurl{ctansystems}, although these are unlikely to be up to +date. Your best bet is to use a current \TEX\ distribution. + +\section{Compiling} + +Given a directory where the sources have been downloaded or checked out, +some working on a \UNIX\ system the following steps are needed to +compile \PDFTEX: + +\begin{verbatim} +cd source # from branches/stable! +./build-pdftex.sh +\end{verbatim} + +The binary \filename{pdftex} will hopefully then end up in the +subdirectory \filename{build-pdftex/texk/web2c}. The additional +utilities \filename{pdftosrc} and \filename{ttf2afm} are in the \PDFTEX\ +source repository, but are not built by default. If they are needed, +edit \filename{build-pdftex.sh} to \type{--enable} them. + +For \PDFTEX\ maintainers: a sibling script to \type{build-pdftex.sh} is +in the repository, namely \type{sync-pdftex.sh}, which syncs changes +from a \TEXLIVE\ source repository to a \PDFTEX\ source repository. Read +and understand the script before using it! + +\section{Placing files} + +The next step is to put the newly-compiled \filename{pdftex} (and, if +enabled, \filename{pdftosrc} and/or \filename{ttf2afm}) binaries into +the installed distribution. \Eg\ for a typical \TEXLIVE\ system:\\ +\texttt{/usr/local/texlive/\rcsyear/bin/}\type{x86_64-linux}, replacing +\type{x86_64-linux} with the appropriate platform name. (As always, it +is sensible to rename the installed \filename{pdftex} binary first and +not just overwrite it.) + +If you're doing this into a live hierarchy, run \verb|fmtutil-sys refresh| +afterwards, so that all formats are regenerated system-wide +with the new \filename{pdftex} binary. + +If what you want is to test a new version of \filename{pdftex}, and not +replace the installed version, the best approach is to copy it into the +binary directory as, say, \filename{pdftex.new}. The different +executable name can sometimes change the files found and other behavior, +but usually this won't matter. + +\PDFTEX\ uses the Kpathsea library to search for supporting files; many +variables and configuration files can come into play. See the Kpathsea +manual: \useurl{kpathsea}. + +\section{Configuration of \PDFTEX} +\label{sec.cfg} + +As opposed to \TEX\ with its \DVI\ output, the \PDFTEX\ program does not +have a separate postprocessing stage to transform the \TEX\ input into +final \PDF. As a consequence, all data needed for building the \PDF\ +must be available during the \PDFTEX\ run, in particular information on +media dimensions and offsets, graphics files for embedding, and font +information (font files, encodings). + +When \TEX\ builds a page, it places items relative to the (1in,1in) +offset from the top left page corner (the \DVI\ reference point). +Separate \DVI\ postprocessors allow specifying the paper size (\eg\ A4 +or letter), so that this reference point is moved to the correct +position on the paper, and the text ends up at the right place. + +In \PDF, the paper dimensions are part of the page definition, and +\PDFTEX\ therefore requires that they be defined at the beginning of the +\PDFTEX\ run. As with pages described by \POSTSCRIPT, the \PDF\ +reference point is in the lower left corner. + +Formerly, these dimensions and other \PDFTEX\ parameters were read in +from a configuration file named \filename{pdftex.cfg}, which had a +special (non-\TEX) format, at the start of processing. Nowadays such a +file is ignored by \PDFTEX. Instead, the page dimensions and offsets, as +well as many other parameters, can be set by \PDFTEX\ primitives during +the \PDFTEX\ format building process, so that the settings are dumped +into the fresh format and consequently will be used when \PDFTEX\ is +later called with that format. All settings from the format can still be +overridden during a \PDFTEX\ run by using the same primitives. This +configuration concept is a more unified approach, as it avoids a +configuration file with a special format. + +A list of \PDFTEX\ primitives likely relevant to setting up the \PDFTEX\ +engine is given in the table below. All primitives are described in +detail in previous sections. + +\begin{smalltable} +\begin{tabular}{@{}llll@{}} +\bf primitive name & \bf type & \bf default & \bf comment\cr +\cs{pdfoutput} & integer & 0 & \DVI\ by default \cr +\cs{pdfadjustspacing} & integer & 0 & off \cr +\cs{pdfcompresslevel} & integer & 9 & best \cr +\cs{pdfobjcompresslevel} & integer & 0 & no object streams \cr +\cs{pdfdecimaldigits} & integer & 3 & \cr +\cs{pdfimageresolution} & integer & 72 & dpi \cr +\cs{pdfpkresolution} & integer & 0 & \cr +\cs{pdfpkmode} & tokens & empty & mode per \type{mktex.cnf}\cr +\cs{pdfuniqueresname} & integer & 0 & \cr +\cs{pdfprotrudechars} & integer & 0 & \cr +\cs{pdfgentounicode} & integer & 0 & \cr +\cs{pdfmajorversion} & integer & 1 & output \PDF\ 1.x \cr +\cs{pdfminorversion} & integer & 4 & specifically \PDF\ 1.4 \cr +\cs{pdfpagebox} & integer & 0 & \cr +\cs{pdfforcepagebox} & integer & 0 & \cr +\cs{pdfinclusionerrorlevel} & integer & 0 & \cr +%---------------------------------------------------------------------------- +\cs{pdfhorigin} & dimension & 1in & \cr +\cs{pdfvorigin} & dimension & 1in & \cr +\cs{pdfpagewidth} & dimension & 0pt & \cr +\cs{pdfpageheight} & dimension & 0pt & \cr +\cs{pdflinkmargin} & dimension & 0pt & \cr +\cs{pdfdestmargin} & dimension & 0pt & \cr +\cs{pdfthreadmargin} & dimension & 0pt & \cr +\cs{pdfmapfile} & text & \filename{pdftex.map} & not dumped\cr +\end{tabular} +\end{smalltable} + +Figure~\ref{fig.configfile} shows a recent \PDFTEX\ configuration file +(\type{pdftexconfig.tex}) from \TEXLIVE\ (part of the +\type{tex-ini-files} package), overriding some of these settings. It is +read when a format is built. It enables \PDF\ output, sets paper +dimensions and the default pixel density for \PK\ font inclusion. The +default values are chosen so that \PDFTEX\ often can be used (\eg\ in +\type{-ini} mode) without setting any additional parameters. + +\begin{figure}[t] +\myverbatiminput{incl/pdftexconfig.txt} +\caption{\PDFTEX\ configuration file for \TEXLIVE\ + (\texttt{pdftexconfig.tex}).} +\label{fig.configfile} +\end{figure} + +Independent of whether such a configuration file is read, the first +action in a \PDFTEX\ run is reading the global \WEBC\ configuration file +(\filename{texmf.cnf}), which is common to all programs in the \WEBC\ +system. This file mainly defines file search paths, the memory layout +(\eg\ string pool and hash size), and a few other general parameters. + +\section{Creating format files} + +The \PDFTEX\ engine supports building separate formats for either \DVI\ +or \PDF\ output in the same way as the classical \TEX\ engine does for +\DVI. Format generation (and other \type{initex} features) is enabled by +the \type{-ini} option. The default mode (\DVI\ or \PDF) can be chosen +either on the command line by setting the option \type{-output-format} +to \type{dvi} or \type{pdf}, or by setting the \cs{pdfoutput} parameter. +The format file inherits this setting, so that a later invocation of +\PDFTEX\ with this format starts in the preselected mode (which can +still be overridden). A format file can be read in only by the engine +that has generated it; a format incompatible with an engine leads to a +fatal error. + +It is customary to package the configuration and macro file input into a +\type{.ini} file. \Eg\ the file \type{etex.ini} in +figure~\ref{fig.etex.ini} is for generating an \ETEX\ format with \DVI\ +output. It has been traditional for many years to generate +\type{etex.fmt} with \PDFTEX\ rather than the original \ETEX, because +\PDFTEX\ contains useful additional programming and other +non-\PDF-related features. + +The \type{pdfetex.ini} file figure~\ref{fig.pdfetex.ini} shows the +corresponding format with \PDF\ output by default; this is what creates +the format file read when \type{pdftex} is normally invoked. + +The corresponding \PDFTEX\ invocations for format generation are: + +\begin{verbatim} +pdftex -ini *etex.ini +pdftex -ini *pdfetex.ini +\end{verbatim} + +These calls produce format files \filename{etex.fmt}, +\filename{pdfetex.fmt}, as the default format file name is taken from +the input file name. You can override this with the \type{-jobname} +option. The asterisk \type{*} before the file name is an unusual flag, +only used in \type{-ini} mode, which causes the \PDFTEX\ engine to +enable \ETEX's features. + +To reiterate, the distribution (\TEXLIVE, \MIKTEX) usually takes care of +format (re)generation. The above is if you need to do such things +manually for testing, debugging, development, etc. + +Incidentally, as of \PDFTEX\ 1.40.21 (\TEX\ Live 2020), \filename{.fmt} +files are compressed with \type{zlib}. This makes for a considerable +savings in space, and consequently in time. + +\begin{figure}[t] +\myverbatiminput{incl/ini-etex.txt} +\caption{The \type{etex.ini} file to dump the plain \ETEX\ format with + \DVI\ output.} +\label{fig.etex.ini} +\end{figure} + +\begin{figure}[t] +\myverbatiminput{incl/ini-pdfetex.txt} +\caption{The \type{pdfetex.ini} file to dump plain \ETEX\ with \PDF\ output.} +\label{fig.pdfetex.ini} +\end{figure} + +\section{Testing the installation} + +When everything is set up, you can test the installation. A simple test +of plain \PDFTEX\ is: + +\begin{verbatim} +pdftex story \\end +\end{verbatim} + +This should typeset the famous one-page short story by A.U. Thor, +generating a \PDF\ file. + +A more thorough and descriptive test is the plain \TEX\ test file +\filename{samplepdf.tex}, available in the distribution in the +\type{samplepdftex/} directory. Process this file by typing: + +\begin{verbatim} +pdftex samplepdf +\end{verbatim} + +If the installation is ok, this should produce a file called +\filename{samplepdf.pdf}. The file \filename {samplepdf.tex} is also a +good place to look for examples of how to use \PDFTEX's primitives. + +\section{Common problems} + +The most common problem with installations is that \PDFTEX\ complains +that some file cannot be found. In such cases, first make sure that all +\TEX-related environment variables are unset. For detailed debugging, +set the environment variable \type{KPATHSEA_DEBUG=255} before running +\PDFTEX\ or use the option \verb|-kpathsea-debug 255|. More options can +be found in the \WEBC\ documentation. + +Variables in \filename{texmf.cnf} can be overwritten by environment +variables. Here are some of the most common problems you can encounter +when getting started: + +\begin{itemize} +\item \verb|I can't find the format file `pdftex.fmt'!| \newline + \verb|I can't find the format file `pdflatex.fmt'!| + + The format file is not created (see above how to do that) or + is not properly placed. Make sure that \type{TEXFORMATS} in + \filename {texmf.cnf} contains the path to \filename {pdftex.fmt} + or \filename {pdflatex.fmt}. + +\item \verb|Fatal format file error; I'm stymied| + + This typically appears if you forgot to regenerate the \type{.fmt} + files after installing a new version of the \PDFTEX\ binary. + The first line tells by which engine the offending format was generated. + +\item \PDFTEX\ cannot find one or more map files (\type{*.map}), + encoding vectors (\type{*.enc}), virtual fonts, Type~1 fonts, + TrueType or OpenType fonts, or some image file. + + Make sure that the required file exists and the corresponding variable + in \filename{texmf.cnf} contains a path to the file. + + When you have installed new fonts, and your \PDF\ viewer complains + about missing fonts, you should take a look at the log file produced + by \PDFTEX. Missing fonts, map files, encoding vectors as well as + missing characters (glyphs) are reported there. +\end{itemize} + +For more help resources of all kinds, see \useurl{tughelp}. + +\chapter{Formal syntax specification} +\label{sec.syntax} + +This appendix formally specifies the \PDFTEX-specific extensions to the +\TEX\ macro programming language. Most primitive names are prefixed by +`\type{pdf}'. General definitions and syntax rules follow after the list +of primitives. + +Two new units of measure were introduced in \PDFTEX\ 1.30.0: the new +Didot ($\mbox{1nd}=0.375$mm) and the new Cicero ($\mbox{1nc}=12$nd). The +former was proposed by \ISO\ in 1975. + +\begingroup + \parindent=0pt + % because the summary is nothing but a long string of \Syntax + % commands, we have to allow breaks, in contrast to the main text. + \def\aftersyntax{\par\vskip 1.5pt plus1pt minus1pt\relax} + +% Generated list of primitives (see Makefile). +\input{incl/pdftex-syntax.tex} + +\section{General definitions and syntax rules} + +\Syntax{ +\Something{general text} \Means + \Lbrace \Something{balanced text} \Rbrace +} + +\Syntax{ +\Something{attr spec} \Means + \Literal{attr} \Something{general text} +} + +\Syntax{ +\Something{resources spec} \Means + \Literal{resources} \Something{general text} +} + +\Syntax{ +\Something{rule spec} \Means + (\Literal{width} \Or \Literal{height} \Or \Literal{depth}) + \Something{dimen} \Optional{\Something{rule spec}} +} + +%\Syntax{\Something{object type spec} \Means +% \Optional{\Literal{stream} +% \Optional{\Something{attr spec}}} \Something{object contents}} + +\Syntax{ +\Something{object type spec} \Means + \Literal{reserveobjnum} + \Or \Next + \Optional{\Literal{useobjnum} \Something{number}} \Next + \Optional{\Literal{stream} \Optional{\Something{attr spec}}} + \Something{object contents} +} + +\Syntax{ +\Something{annot type spec} \Means + \Literal{reserveobjnum} + \Or \Next + \Optional{\Literal{useobjnum} \Something{number}} + \Optional{\Something{rule spec}} + \Something{general text} +} + +\Syntax{ +\Something{object contents} \Means + \Something{file spec} + \Or \Something{general text} +} + +\Syntax{ +\Something{xform attr spec} \Means + \Optional{\Something{attr spec}} \Optional{\Something{resources spec}} +} + +\Syntax{ +\Something{image attr spec} \Means + \Optional{\Something{rule spec}} + \Optional{\Something{attr spec}} + \Optional{\Something{page spec}} + \Optional{\Something{colorspace spec}} + \Next \Optional{\Something{pdf box spec}} +} + +\Syntax{ +\Something{outline spec} \Means + \Optional{\Something{attr spec}} + \Something{action spec} + \Optional{\Literal{count} \Something{number}} + \Something{general text} +} + +\Syntax{ +\Something{action spec} \Means + \Literal{user} \Something{user-action spec} + \Or \Literal{goto} \Something{goto-action spec} + \Or \Next \Literal{thread} \Something{thread-action spec} +} + +\Syntax{ +\Something{user-action spec} \Means + \Something{general text} +} + +\Syntax{ +\Something{goto-action struct spec} \Means + \Literal{struct} (\Something{numid} \Or \Literal{nameid} \Or \Something{general text}) +} + +% keep in sync with redundant copy below. +\Syntax{ +\Something{goto-action spec} \Means + \Optional{\Something{goto-action struct spec}} \Something{numid} + \Or \Next \Optional{\Something{file spec}} \Optional{\Something{goto-action struct spec}} \Something{nameid} + \Or \Next \Optional{\Something{file spec}} \Optional{\Something{goto-action struct spec}} \Optional{\Something{page spec}} \Something{general text} + \Or \Next \Something{file spec} \Optional{\Something{goto-action struct spec}} \Something{nameid} \Something{newwindow spec} + \Or \Next \Something{file spec} \Optional{\Something{goto-action struct spec}} \Optional{\Something{page spec}} \Something{general text} \Something{newwindow spec} +} + +\Syntax{ +\Something{thread-action spec} \Means + \Optional{\Something{file spec}} \Something{numid} + \Or \Optional{\Something{file spec}} \Something{nameid} +} + +\Syntax{ +\Something{colorspace spec} \Means + \Literal{colorspace} \Something{number} +} + +\Syntax{ +\Something{pdf box spec} \Means + \Literal{mediabox} + \Or \Literal{cropbox} + \Or \Literal{bleedbox} + \Or \Literal{trimbox} + \Or \Literal{artbox} +} + +\Syntax{ +\Something{map spec} \Means + \Lbrace \Optional{\Something{map modifier}} + \Something{balanced text} \Rbrace +} + +\Syntax{ +\Something{map modifier} \Means + \Literal{+} \Or \Literal{=} \Or \Literal{-} +} + +\Syntax{ +\Something{numid} \Means + \Literal{num} \Something{number} +} + +\Syntax{ +\Something{nameid} \Means + \Literal{name} \Something{general text} +} + +\Syntax{ +\Something{newwindow spec} \Means + \Literal{newwindow} \Or \Literal{nonewwindow} +} + +\Syntax{ +\Something{dest spec} \Means + \Optional{\Literal{struct} \Something{number}} + (\Something{numid} \Or \Something{nameid}) + \Something{dest type} +} + +\Syntax{ +\Something{dest type} \Means + \Literal{xyz} \Optional{\Literal{zoom} \Something{number}} + \Or \Literal{fitr} \Something{rule spec} + \Or \Next \Literal{fitbh} + \Or \Literal{fitbv} + \Or \Literal{fitb} + \Or \Literal{fith} + \Or \Literal{fitv} + \Or \Literal{fit} +} + +\Syntax{ +\Something{thread spec} \Means + \Optional{\Something{rule spec}} + \Optional{\Something{attr spec}} + \Something{id spec} +} + +\Syntax{ +\Something{id spec} \Means + \Something{numid} \Or \Something{nameid} +} + +\Syntax{ +\Something{file spec} \Means + \Literal{file} \Something{general text} +} + +\Syntax{ +\Something{page spec} \Means + \Literal{page} \Something{number} +} + +\Syntax{ +\Something{expand spec} \Means + \Something{stretch} + \Something{shrink} + \Something{step} + \Optional{\Literal{autoexpand}} +} + +\Syntax{ +\Something{stretch} \Means + \Something{number} +} + +\Syntax{ +\Something{shrink} \Means + \Something{number} +} + +\Syntax{ +\Something{step} \Means + \Something{number} +} + +\Syntax{ +\Something{pre spec} \Means + \Literal{pre} +} + +\Syntax{ +\Something{stack action} \Means + \Literal{set} \Or \Literal{push} \Or \Literal{pop} \Or \Literal{current} +} + +\endgroup % of syntax definitions + +\medskip + +A \Something{general text} is expanded immediately, like \cs{special} +in traditional \TEX, unless explicitly mentioned otherwise. + +Some of the object and image-related primitives can be prefixed by +\cs{immediate}. + +\chapter{Abbreviations used in this manual} + +In this document we use numerous abbreviations. For convenience we give +their meanings here. + +\abbrevlist + +\twocolumn {\small \emergencystretch=1.5em \input{incl/fdl-1.2.tex}} + +\end{document} |