[PYTHON] [Blender] How to make Blender scripts multilingual

There was a bit of talk on Twitter about how Blender scripts can be multilingual, as the Blender documentation is confusing. As a result of various investigations, I managed to support multiple languages, so I will introduce it with a sample.

sample

Here are some samples that support multiple languages. This time, I simply tried to support the following two languages.

• English
• Japanese

translation.py

import bpy

bl_info = {
    "name" : "Translation Test",
    "author" : "Nutti",
    "version" : (0, 1),
    "blender" : (2, 7, 0),
    "location" : "UV > Translation Test",
    "description" : "Translation Test",
    "warning" : "",
    "wiki_url" : "",
    "tracker_url" : "",
    "category" : "UV"
}

#Translation dictionary
translation_dict = {
    "en_US" :
        {("*", "Test: ") : "Test: %d"},
    "ja_JP" :
        {("*", "Test: ") : "Tesuto: %d"}
}


class TranslationTest(bpy.types.Operator):
    bl_idname = "uv.translation_test"
    bl_label = "Translation Test"
    bl_description = "Translation Test"
    bl_options = {'REGISTER', 'UNDO'}
    
    def execute(self, context):
        num = 50
        #Display translation results in notification bar
        self.report({'INFO'}, bpy.app.translations.pgettext("Test: ") % (num))
        return {'FINISHED'}


def menu_func(self, context):
    self.layout.separator()
    self.layout.operator(TranslationTest.bl_idname)


def register():
    bpy.utils.register_module(__name__)
    bpy.types.VIEW3D_MT_uv_map.append(menu_func)
    bpy.app.translations.register(__name__, translation_dict)   #Dictionary registration


def unregister():
    bpy.app.translations.unregister(__name__)   #Delete dictionary
    bpy.utils.unregister_module(__name__)
    bpy.types.VIEW3D_MT_uv_map.remove(menu_func)


if __name__ == "__main__":
    register()

How to use

Follow the steps below to install. Blender Wiki

1. Japaneseize Blender
2. Execute "Translation Test" from the menu displayed by pressing the'U'key in Edit mode.
3. Confirm that the notification bar shows "Test: 50"
4. Translate Blender into English
5. Execute "Translation Test" from the menu displayed by pressing the'U'key in Edit mode.
6. Confirm that "Test: 50" is displayed in the notification bar.

How to change Blender language

The following will help you to change the language of Blender. blender.jp

Sample explanation

For the basic part, see [\ Blender ] How to make a Blender plugin. This time, I will concentrate on the multilingual part.

Definition of translation dictionary

Define a dictionary for translation. The format of the dictionary is as follows.

{locale: {(context, key): translated_str, ...}, ...}

Each parameter is shown below.

In this sample, the dictionary is defined as follows.

translation_dict = {
    "en_US" :
        {("*", "Test: ") : "Test: %d"},
    "ja_JP" :
        {("*", "Test: ") : "Tesuto: %d"}
}

Tips: How to get the locale

Some people may not know what to specify, even though it is a locale. In such a case, try the following from the Python Console provided in Blender. You can find out the current locale of Blender.

>>> bpy.app.translations.locale
'en_US'

Registration of translation dictionary

To register a dictionary for translation, execute the following in the register function.

bpy.app.translations.register(__name__, translation_dict)

Perform translation

To get the translated string from the specified key, use bpy.app.translations.pgettext as follows.

bpy.app.translations.pgettext("Test: ") 

If you want to use ** string format **, use bpy.app.translations.pgettext_iface.

bpy.app.translations.pgettext("Test: ") % (num)

Delete translation dictionary

The registered translation dictionary must be released when the add-on is stopped. To unregister a dictionary, execute the following in the unregister function.

bpy.app.translations.unregister(__name__)

in conclusion

I showed you how to make Blender scripts multilingual. By making the script compatible with multiple languages, there is a high possibility that the script will be used for the supported languages. Blender is still widely used in English-speaking countries, so if you are writing scripts for Japanese, why not take this opportunity to support English as well? ** By supporting English, you may be able to get feedback and get acquainted with people from overseas **.

Reference information

• Blender 2.69.1 - API documentation-
• Project that actually performs Blender translation