Khmer Script in TeX with GNU/Linux examples

TeX is an open source typesetting system invented by Prof. Donald E. Knuth. One of TeX’s offspring is LaTeX which provides high-level commands similar to HTML. LaTeX was developed on TeX engine by Leslie Lamport. People use LaTeX to write books, theses and journal articles. One of its final output can be a Postscript file or a PDF file. One can make an lazy comparison between TeX and a word processor. However, they are very different, and TeX is far better than any word processor.

There is one difficulty with TeX is that it can be difficult to do some custom documents such as producing a document with Khmer scripts. Four years ago, I was to embark upon a new thesis for Khmer spell checker with my own proposal and initiative at the ANU. From the beginning, I pressed upon myself to find a way to make TeX produce Khmer scripts since it would be disastrous to write my thesis with some mathematics formulas. What I like best about TeX is that I didn’t have to care about any style or format. Most of my time was spent on generating my ideas and focus on writing since I was not a natural writer.

Let’s go to the real stuff. You may be bored with my non-sense words. It starts with a sample example. It contains pk and tfm fonts which are used by TeX and dvi driver. It also contains a macro file mapping each glyph to the human readable command. For example, short cutting the instruction that tells TeX to use a glyph at position char66 in font ‘a’ to \aksaaka. Here is the sample file: khtex . Download it at your own risk, follow your common sense and read README file. The file name is supposed to be khtex.tar.gz, but the free site I used to upload it does not like dot as part of the file name. You may need to put a dot before tar if your compression software needs it.

Glyphs in TeX are like characters in Limon or ABC. Don’t confuse a glyph and a Unicode character. A Khmer Unicode character does not necessary correspond to a glyph. Many Khmer vowels are composed of more than one glyph. Unicode represents the logical concept while a font system is the concrete representation.

If you’re very interested in what I have done and want to learn it urgently so that you can create Khmer pk and tfm fonts from a different truetype font, please send me a reminder at hputhick [_AT] gmail dot com. Otherwise, I will write it at my own pace whenever I feel like writing it. Next parts include a script to convert a piece of Khmer unicode string into a string of the TeX macros I talked earlier. How to convert a TTF into PK and TFM font at any size. This has to go through metafont which has lots history and copyright issues. If you don’t go through metafont, you can only convert a TTF into a PK and TFM at the default font size which is 10pt as far as I know. If you think otherwise and don’t mind to share your technique, please spare some of your free time to give me some guidance.

I love GNU Emacs

I started using GNU Emacs or Emacs in 2004 when I went to the ANU. I love it ever since. I will you why Emacs is the best text editor I ever used. Emacs keyboard commands are really efficient. I split window at a fraction of second, copy and paste from one window onto another without moving my hand away from the keyboard. I don’t have to remember every variable either in the same file or in a different file. I can split the window into 2 panels and open the file that I need to know the variable name while writing a new file. It is even better when text-based Emacs can do the same thing. Text-based Emacs becomes handy when I need to do these things remotely via ssh which is far more efficient than vnc. Most of the times servers don’t run in graphic mode. Vi cannot deliver these functionalities that Emacs can. Vi is good at small update or creation job while Emacs can do heavy work over an ssh connection. Emacs supports C, C++, Perl, Python, Java, Ruby and of course Lisp indentation. It can convert indentation tab character in spaces and vice versa.

Emacs is a simple tool but more efficient than most Integrated Development Environment tools. I need to learn and master one tool for every language I will have to learn and use rather a dozen of them. GNU Emacs is not only available on GNU Linux but Microsoft Windows and Mac as well. So, one tool will be the job for many languages and many platforms. So why not. It makes my life a lot easier.

Even though Emacs is efficient, it can be a bit tricky to understand the keyboard commands. “C” and “M” for pressing and hold Ctrl and Atl keys. Fair enough, C for Ctrl but what about M. M is for Meta key in Macintosh, which is equivalent to Atl in PC. These command reference cards below are from “Learning GNU Emacs” book.

Emacs command reference card page 1

Emacs command reference card – page 2