Thai on Amiga

It is easy to use Thai language for everyday computing tasks on an Amiga or Amiga-compatible computer. On this page I will address the following issues:

• Viewing and editing Thai text.
• Email set up.
• Converting text coding.

I'm going to assume that you are working in the TIS-620 standard coding for Thai text, the most commonly used coding, but you can easily convert to the other formats.

BareEd and Thai

BareEd, by Joerg van de Loo is a text editor for Amiga that supports proportional fonts. By selecting a font that has Thai characters and Thai keymap it is possible to type in Thai. I have been using this method to edit Thai documents, email, web pages etc for several years.

Recently, with the aid of my consultancy, hassle and a few lines of code, Joerg has kindly implemented improved support specifically for Thai.

Special features that support Thai:

• Improved rendering of Thai fonts - developed using my Thai fonts and thus ensuring good quality display. This is essential as most text editors do not properly respect the negative kerning required by Thai fonts when using the standard Amiga font rendering system.
• The cursor only moves between consonants and in-line vowels to avoid being lost in composing characters (i.e. tone markers, above and below vowels and diacritics).
• Pressing delete can optionally delete the character to the right of the cursor or the character to the right plus all composing characters.
• WTT 2 Standard compliant:
  
  • Invalid letter combinations can be prevented from being input, for example leading vowels must be followed by a consonant.
  • Invalid letter combinations are displayed such that it is much easier to see mistakes.
  • 3 levels of checking available (as per specification): pass through, basic check and strict.

Editing an HTML file from speakrealthai.com in BareEd

Without these features I often typed Thai text that looked fine but only after closer inspection or viewing on other platforms I could see that there were mistakes. Often, this is because the other platform's software did not understand the Thai locale and the font rendering broke.

Depending on the font and the application, sometimes mistakes looked correct and sometimes they made the word unreadable. Using the WTT specification it is possible to ensure that texts are correct so that they can render properly and that mistakes look consistent across different software and platforms. Now these features are implemented in BareEd, I can rest assured that any mistakes are in my use of language and not in my typing.

Editing the Thai word for water

Guide to the above image: Left: BareEd before Thai support - a word has been entered with an invalid sequence of letters. Middle: BareEd with Thai support - in strict mode the sequence checker makes it impossible to type incorrect sequences so in this case the author was forced to type the correct letter order. Right: BareEd with Thai support - in pass through mode a space is inserted before invalid characters allowing the user to identify the mistake more easily. Without the extra space inserted by pass through mode, it is quite difficult to see the difference between correct and incorrect, however you may deliberately type invalid sequences in the rare case you need to.

Getting Started with BareEd and Thai

Using Thai with BareEd is easy. You just need to follow these steps:

1. Using a Thai keymap, start BareEd.
2. Select a Thai font, e.g. lhthai 24 point.
3. Switch BareEd to TIS-620 mode.
4. Select the level of stringency when checking Thai input.

Steps 2, 3 and 4 can be set by editing the icon tooltypes.

During the development of these new features it has been possible to spot ways to improve the quality of my Thai fonts; for example certain combinations of letters are not valid so this gave me space to draw better looking letters. Also, the fact that a complete Thai implementation was going to be realised encouraged me to draw all the glyphs that were missing from my fonts because they were very rare or never used.

Working together with Joerg, we now have a viable Thai text editor and better fonts. Please contact me (emptystate at yahoo dot co dot uk) if you need help using BareEd with Thai.

The sequence validator is available as a separate tool in my thaicheck program.

Email Configuration

Using BareEd with YAM

BareEd with a Thai font can be used for reading and writing email. When you reply to an email you can choose an external editor such as BareEd.

In order to use BareEd as the outgoing mail editor, set the YAM configuration. Select the path to BareEd by clicking the file icon next to the External editor string gadget.

Setting YAM MIME Header

To be safe, it is best to set a MIME header in your email to indicate that it is in Thai. In YAM this can be achieved by setting the field as shown in this image:

Useful Tools

Converting Text Coding to TIS-620

If you receive a Thai file or email in a format other than TIS-620, convert it using thaiconv. thaiconv can guess the format but see my Thai email guide for information and YAM screen grabs to determine which format your message is in.

Validating Thai Letter Order in Text Files

A sequence validator is available compiled for Amiga, see my thaicheck program.

Recover Thai Email in Japan

If you are in Japan you may need to recover Thai email that has been cross coded to a Japanese coding. See jax2th, a tool to recover email. Binaries available for Amiga.