Creating Custom Alphabets

If your language is not already supported in Dasher, you can add support by creating an alphabet file and providing training text. This guide will walk you through the process.

Overview

Dasher uses two main components to support a language:

1. Alphabet file (alphabet.xml) - Defines the characters and their order
2. Training text - A sample of natural writing (300K or more) to teach Dasher character probabilities

Step 1: Create the Alphabet File

The alphabet file is an XML file that defines all characters in your language and their display order in Dasher.

<?xml version="1.0" encoding="UTF-8"?>
<alphabet name="MyLanguage">
  <!-- Define character groups -->
  <group label="Lowercase">
    <char d="a" />
    <char d="b" />
    <!-- more characters... -->
  </group>
<group label=“Uppercase”>
<char d=“A” />
<char d=“B” />
<!— more characters… —>
</group>
<group label=“Numbers”>
<char d=“0” />
<char d=“1” />
<!— more characters… —>
</group>
<group label=“Punctuation”>
<char d=” ” /> <!— space —>
<char d=”.” />
<char d=”,” />
<!— more punctuation… —>
</group>
</alphabet>

Character Attributes

Characters can have various attributes:

• d - The character itself (display)
• t - Text output (if different from display)
• colour - Color for the character box
• label - Display label for character groups

Combining Characters

For languages with combining characters (like Thai), use special handling:

Step 2: Prepare Training Text

Training text helps Dasher learn the probability distribution of characters in your language.

Requirements

• Size: At least 300KB of text (more is better)
• Content: Natural writing in your target language
• Format: Plain text file, UTF-8 encoded
• Quality: Representative of typical usage

Sources for Training Text

Creating Your Own Training Text

For best results, create training text that matches your personal writing style. Collect emails, documents, or other text you’ve written in the target language.

Step 3: Install the Files

Step 4: Test and Refine

Testing Your Alphabet

1. Start Dasher and select your new alphabet
2. Try writing some sample text
3. Check that all characters appear correctly
4. Verify character order makes sense for your language

Troubleshooting

Advanced Topics

Context-Dependent Characters

Some languages have characters that change form based on context. Dasher can handle this through special XML attributes and context rules.

Multiple Input Methods

For languages with multiple input methods (like different keyboard layouts), you can create multiple alphabet files with different context attributes.

Sharing Your Alphabet

If you create an alphabet for a language not yet supported, please consider contributing it to the Dasher project!

Resources and References