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diff --git a/Build/source/libs/t1lib/t1lib-5.1.2/doc/intro.tex b/Build/source/libs/t1lib/t1lib-5.1.2/doc/intro.tex deleted file mode 100644 index 6d290fd89c4..00000000000 --- a/Build/source/libs/t1lib/t1lib-5.1.2/doc/intro.tex +++ /dev/null @@ -1,217 +0,0 @@ -%---------------------------------------------------------------------------- -% ----- File: intro.tex -% ----- Author: Rainer Menzner (Rainer.Menzner@web.de) -% ----- Date: 2001-06-03 -% ----- Description: This file is part of the t1lib-documentation. -% ----- Copyright: t1lib is copyrighted (c) Rainer Menzner, 1996-2001. -% As of version 0.5, t1lib is distributed under the -% GNU General Public Library License. The -% conditions can be found in the files LICENSE and -% LGPL, which should reside in the toplevel -% directory of the distribution. Please note that -% there are parts of t1lib that are subject to -% other licenses: -% The parseAFM-package is copyrighted by Adobe Systems -% Inc. -% The type1 rasterizer is copyrighted by IBM and the -% X11-consortium. -% ----- Warranties: Of course, there's NO WARRANTY OF ANY KIND :-) -% ----- Credits: I want to thank IBM and the X11-consortium for making -% their rasterizer freely available. -% Also thanks to Piet Tutelaers for his ps2pk, from -% which I took the rasterizer sources in a format -% independent from X11. -% Thanks to all people who make free software living! -%---------------------------------------------------------------------------- - -\newpage -\section{Introduction} -\subsection{What Does \tonelib\ Do?} -\tonelib\ is a library written in the C programming language -allowing a programmer to generate bitmaps from Adobe (TM) Type 1 fonts -quite easily. These bitmaps are returned in a data structure -with type {\ttfamily GLYPH}. This special -{\ttfamily GLYPH}-type is also used in the X11 window system to -describe character bitmaps. It contains the bitmap data as well as -some metric information. But \tonelib\ is in itself entirely independent -of the X11-system or any other graphical user interface. - -Given that the X11-system is probably the most frequently used -window system in the UNIX-world, and furthermore assuming that most -graphical applications run under window systems, it appears that -\tonelib\ implements functionality already provided by the -graphical user interface, -the X11-system. Thus the question arises: Why not use X11 directly for -rastering characters? Well, the answer is quite simple; the X11 Font -machinery appears to be too {\em static} in order to use it for -certain purposes. Moreover X11-calculations and positioning of -characters are based on bitmap -dimensions and are thus subject to error accumulation. - -Here is a list of features which are supported in the current release -of \tonelib. -\begin{itemize} -\item Rasterizing is done as characters get requested. The X11-server, - in contrast, - rasters a font completely at a given size - when it is loaded. {\em Rastering on demand} saves time when the - font is loaded the first time and saves memory since often only the - alphabetic letters and a few other characters are needed. -\item The encoding mechanism of PostScript is fully supported. The - user may use the fonts' internal or some other encoding. - Additional encoding files can be loaded at runtime and fonts can be - reencoded at runtime. The syntax of encoding files is - straight-forward and simple. -\item The library makes use of Adobe Font Metric data in the form of - AFM files. This may seem a disadvantage, but in order - to make decent typesetting possible, some more information than that - contained in Type 1 font files is needed. Besides, Adobe makes - these AFM files freely available on their ftp-server for all - registered Type 1 fonts. -\item In case AFM files are missing, \tonelib\ is able to generate - metrics information in charspace accuracy by rastering each - character at 1000~bp. -\item In addition to generation of character bitmaps, there is a way - to directly raster strings of any length in a given font. - The space-width may explicitly be corrected by the user. This - may be needed by word processing applications. -\item Strings may be rastered - optionally using pairwise kerning information from - the AFM file. Kerning is an important feature of good - quality typesetting. - Kerning information can also be requested by the user without - rasterization. -\item Ligature information is made available to the user in an - efficient way. Use of Ligatures is another characteristic of good - typesetting. As to my - knowledge, only \TeX\ and all related macro-packages are able to - handle ligatures in a natural and efficient way. -\item Rotation and arbitrary transformation on the fly is supported. -\item \tonelib\ supports antialiasing. In this case, a pixel is - represented as a byte, word or double word. Antialiasing is - implemented by subsampling with factor 2 or 4 alternatively. - If you use the X11-interface introduced in \tonelib\ V.\ 0.3-beta, - even colored antialiasing between any pair of colors is provided in a - completely transparent way. -\item In addition to transformation on the fly, two transformation - types---{\em slanting} and {\em extending}---are possible on the fontlevel - including bitmap caching. Horizontal expansion of fonts is fully supported - and since version 0.3-beta also {\em slanting} of fonts is nearly fully - supported. For restrictions and drawbacks of slanting fonts see - \ref{transformations} on page \pageref{transformations}. -\item Paths, the library searches for the different needed file types - are specified at runtime by means of a - configuration file. They may thus be changed without needing to - recompile the application. For example, the directories of the - X11-system's Type 1 font files may be specified there in order to use - these fonts with the library. A user may have his own configuration file and - as a fallback/default there is a system wide configuration file. This should - be setup when the library is installed. -\item Since of version 0.3-beta a special set of functions is provided which - implements a more comfortable X11-interface. This is due to the fact that - X11 is the only standard window system in the UNIX world. However, as before - \tonelib\ may be compiled and used without even having X11 installed. -\item Some decorations like {\em underlining} are supported by simply setting - a flag for the rastering functions. -\item {\em Right To Left} typesetting is supported. -\item Font subsetting is easily achieved using a high level function. This - makes it easier for application to efficiently export Postscript files. -\item Composite character information can be retrieved. Moreover, \tonelib\ - transparently handles and realizes composite character definitions from AFM - files. -\end{itemize} -There are also some problems and features not yet -implemented, but likely to be implemented in the future. -The main problem up to now is: -\begin{itemize} -\item The font cache isn't a font cache really. At this time all - bitmaps are saved by always allocating more memory from the - system. No automatic removal of bitmaps no longer needed is - done. However, the user has the possibility of explicitly - removing data, if he thinks it is not needed anymore. -\end{itemize} - -\subsection{Copyrights and Credits} -There are some copyrights on parts of the library and there are some -programmers (or corporations) which I want to give credit. -The library uses: -\begin{itemize} -\item[--] all internal parts of the X11-rasterizer donated to - the X11-project by IBM. This rasterizer does the {\em real} hard - work of scan-conversion. -\item[--] the modifications to the rasterizer done by Piet - Tutelaers in his ps2pk-package. The main purpose was decoupling the - sources from the X11-system sources. -\item[--] the \verb+parse_AFM+ software which was made freely available - by Adobe. This is used to parse the AFM files (what - a surprise) and to generate the data structures the information is - saved in. -\end{itemize} - -Raph Levien (\verb+raph@acm.org+) contributed an algorithm for -sampling down non-antialiased bitmaps to antialiased bitmaps in a very -efficient manor. This makes antialiasing a lot faster. - -Fred L.\ Drake, Jr. (\verb+fdrake@acm.org+) wrote a Python interface to -\tonelib, which is distributed with \tonelib. This wrapper is called -\verb+t1python+ and allows Python-programmers to use Type 1 fonts. I -can not tell anything more on this topic since I do not know the -Python language. All questions concerning the Python interface should -thus be addressed to Fred L.\ Drake, Jr. - -Evgeny Stambulchik (\verb+fnevgeny@plasma-gate.weizmann.ac.il+), maintainer of -the \verb+grace+-project---a descendent of \verb+xmgr+, never gets tired of -finding and reporting (and fixing) bugs in \tonelib. Other members of this -project spent time in porting \tonelib\ to further systems: -\begin{itemize} -\item Ed Vigmond (\verb+vigmonde@IGB.UMontreal.CA+): IRIX-port, -\item John Hasstedt (\verb+John.Hasstedt@sunysb.edu+): VMS-port, -\item Alexander Mai (\verb+st002279@hrzpub.tu-darmstadt.de+): OS/2-port. -\end{itemize} - -Hirotsugo Kakugawa (\verb+h.kakugawa@computer.org+) added support for GNU -\verb+libtool+ to \tonelib. - -David Huggins-Daines (\verb+bn711@freenet.carleton.ca+) spent effort in -finding memory leaks and maintains a Debian-package of \tonelib. - - -\begin{center} - \Large Thanks to all these people \\ - and to all those contributors not mentioned here! -\end{center} - -\subsection{Motivation} -The idea of writing this library was due to the SciTeXt-project which -was founded in 1996. They needed a font raster system with some more -functionality than X11 provided. You may find that some things (for -example the format of the font database file) is really closely -related to SciTeXt. In February '{}97 the SciTeXt developers decided to -migrate from C to Java and did not need a font rasterizer any more. Since I -thought there could be other applications for this library I continued the -work on it and voila. - -I have removed the history description which followed at this place in some -previous versions. The history can be roughly viewed in the file \verb+Changes+ -which is located in the toplevel directory of the distribution. - - -\subsection{How to Reach the Author/How to Get \tonelib} -If you have questions, comments or bug reports, you can reach me by -eMail. The address is -\begin{center} -\verb+Rainer.Menzner@web.de+ -\end{center} -If you have bug-reports, it would be best if you could reproduce the error -using the test program \verb+xglyph+ (see \ref{xglyph}). - -\tonelib\ is available by anonymous ftp as\\[5mm] -\verb+ftp://sunsite.unc.edu/pub/Linux/libs/graphics/t1lib-+$x.y[.z]$\verb+.tar.gz+ -\\[5mm] -Here, $x.y.z$ is the version identifier and the brackets around $z$ indicate -that this entry is optional. - -%%% Local Variables: -%%% mode: latex -%%% TeX-master: "t1lib_doc" -%%% End: |