Internationalization

This article deals with the localisation/translation of both TDM itself, as well as Fan Missions.

The I18N support in TDM will only work with v1.07 or newer.

I18N, L10N?

I18N stands for internationalisation (the 18 means there are 18 letters missing between I and N), and L10N stands for localisation.

For Users

You can switch the language of TDM in the Settings menu under Video, General. The language is stored in the CVAR tdm_lang. Ignore sys_lang.

Switching the language does not require a newstart, except for some languages like Russian. There the game will inform you that you need to restart it manually, or the display will not look correct.

Changing the language will change the language of the HUD, as well as the inventory immidiately. It can also be done during a mission.

Note: Not all FMs are yet multi-lingual, and for these certain inventory items, the objectives, or readables might appear in English.
See the list of already internationalized FMs and their status.

For Mappers

As a mapper, you want to reach an audience as wide as possible with your FM. One way is to provide alternative language versions of your map. There are two ways that can be achieved:

1. You can ignore the issue, and hope that somebody else modifies your FM and provides a translation. The past shows that the changes that someone does this are slim, tho. Only a handful of FMs were every translated, most of them only into one other languages. That is because modifying and translating an FM are quite a lot of work, and translators would rather just translate things than to muck around with your PK4 file.
2. You can (from v1.07 on) build in support for translation from the beginning, and make the work for translators easier.

The second point can achieved in two ways:

1. You build the FM with hard-coded strings like 'Silver Key', and then use I18N.pl to transform the FM into a package that can have external dictionaries. That might be easier to work with in DR (as DR itself has no support for dictionaries yet), but the script might not be 100% correct and you need to manually help it out.
2. You build your FM with string templates like "#str_12345" instead of hard-coded names, and supply an external dictionary with these strings.

FM specific dictionaries

Please see the main article about about translating FMs for details.

Inventory Item Names with multiple lines

If you have an inventor item name which is very long, you can insert \n to split it up into two (but not more!) lines:

"#str_20000" "This is a very very\nlong item name."

You should try in the game to see how it looks, so that both lines are roughly the same length.

For Developers

CVAR tdm_lang

The D3 CVAR sys_lang is restricted to a few hard-coded values, and is thus not usable. We have added a new CVAR tdm_lang, which contains the current language as English lower-case string, e.g. "english", "german", "portuguese" etc. This variable is controlled by the GUI via a call back into the SDK code, which switches the language underneath, and also reloads the GUI.

If you change the CVAR manually (via the console f.i.), you need to restart TDM so it works!

Code

The main translation object is of the class CI18N (which is short for "Class Internationalization") and lives in Darkmod/I18N.cpp and Darkmod/I18N.h.

Charset

The D3 code that handles the GUI bitmap font can only load a specific range of bytes as characters. To get the most out of the available entries, an special charset (based on ISO 8859-1 with modifications) is used. The details can be found on this page.

New Strings

If you need to add a new string, follow these steps:

• search for a fitting, free ID in strings/all.lang.
• Add your string there. If possible, add any translation you can, or ask the translators to translate it for you.
• re-generate the language files with perl devel/gen_lang.pl

Note that if the translations for the new strings (or any other string) are missing, the script will substitute the English variant - so you should always have at least the English variant.

The other translations are optional, but if they are added later, you need to re-run perl devel/gen_lang.pl! See also the next point:

Always edit all.lang with a UTF-8 editor and keep it in UTF-8.

Never edit the other language files manually, they will be regenerated and your edits will be lost.

Missing Translations

The following will generate files called "missing_language.txt" in the darkmod directory:

perl devel/gen_lang.pl --missing

Note that the script can no differentiate between a string that was not translated, and a string that is the same even after translation. An example is "Normal" in English, and German. This will be listed as missing string in missing_german.txt.

To avoid that, add the following comment:

"#str_03005"    "Normal"                        // stays the same

to each language variant where the string is unchanged after translation.

Since it can be a bother to ask translators for a new string translation every other day, the current solution is to gather strings for a while, then regenerate the missing_xyz.txt files, and then ask the translators for a translation.

See also the List of TDM translators.

Relocating String IDs

Note: Relocation of string IDs can only be done either before release, or when it is clear that this string is not used by any FM, otherwise you break FMs!

perl devel/rename_string.pl FIRSTOLDID FRISTNEWID COUNT

Example:

perl devel/rename_string.pl 2236 2298 2

GUI

To work around the choiceDef bug, two new main menu commands have been added, called "initChoice" and "stepChoice". These two take 3 arguments each:

1. the CVAR name
2. the labels for each choice (should be in the form '#str_01234" to make it translatable)
3. the values for each choice (usually a hard-coded list like '0;1')

In addition to these, a few GUI #defines where added that make it easier to add a new choice def. Here is how it looked before:

choiceDef PostProcessing
{
    rect            SETTINGS_X_OFFSET, 54, 80, 14
    choices         "#str_07300" // disabled, enabled
    values          "1;0"
    cvar            "r_postprocess"
    choiceType      0
    font            SETTINGS_FONT
    textscale       SETTINGS_FONT_SCALE_CHOICE
    textalign       1
    textaligny      0
    forecolor       SETTINGS_FONT_COLOUR

    onAction
    {
        set "cmd" "play sound/meta/menu/mnu_select" ;
        resetTime "UpdateBloomSliderVisibility" 0;
    }
}

And here is how it has to look now:

windowDef PostProcessing
{
    rect            SETTINGS_X_OFFSET, 54, 80, 14
    text            "gui::r_postprocess_text"
    CHOICE_INIT     "initChoice 'r_postprocess' '#str_07300' '1;0'" }
    CHOICE_STEP     "stepChoice 'r_postprocess' '#str_07300' '1;0'"; resetTime "UpdateBloomSliderVisibility" 0; }
}

Notes:

• use windowDef, not choiceDef, or the GUI will crash upon load.
• the text variable has to be in the format "gui::cvarname_text" (e.g. the CVAR with "_text" appended)
• The lines for "CHOICE_INIT" and "CHOICE_STEP" must end with a "}".
• The secondary action in CHOICE_STEP (resetTime in the example above) is optional.

Known bugs

Sadly, there are quite a lot of limitations in the D3 SDK that prevent a few things from fully working. Once D3 goes open source, these things will be fixed, in the meantime we hope that you can live with the quirks:

• Doom3 does not support the character 0xFF in fonts rendered, but this character is used f.i. in Russian. To work around this, the character 0xFF is moved to 0xB& during loading of dictionaries. The russion font then simply contains a character 0xB6 with the proper image in place.
• choiceDefs do not properly display choices with high-bit characters. There exist two new menu commands and a few #defines to work around this, see the GUI section above.

See Also

• I18N - Main article

Translation resources

• The charset TDM fonts use
• I18N.pl - a script to transform a FM into a mission and I18N data
• Bug Tracker entry #2779
• Text Decals for Signs etc.
• Fonts in TDM
• Font Conversion & Repair - with links to ExportFontToDoom3, Q3Font, Refont, and Font Patcher

Overview of translations

• I18N Status - Which FMs are translated into which language (not entirely up to date)
• Translating FMs
• List of translators
• Translator's Guide

Translation discussions

• Internationalization (Language) usage in TDM - Coverage of the topic by Tels.
• Translating the GUI
• The Dark Mod translation
• About localizing
• Translating missions: Mission author consensus request
• Discussion on state and accessibility of localizations back in 2013