Project Architecture

Kanji Master is built on a modular architecture that clearly separates data logic (Backend) and presentation (UI). This facilitates maintenance, feature expansion, and testing.

Tech Stack

• Language: Rust (Edition 2024)
• Graphics Engine: eframe (wrapper over egui) — Immediate Mode GUI.
• Database: SQLite (via the rusqlite crate).
• Serialization: serde + serde_json / toml.
• Resource Embedding: rust-embed (for DB, JSON, fonts, and SVG).

Module Structure

back (Backend)

Contains business logic independent of the GUI:

• core.rs — working with SQLite (core.db), Kanji structures.
• config.rs — configuration management (config.toml).
• localization.rs — handling TOML UI localization.
• translation.rs — handling JSON kanji translations and examples.
• recognition.rs — logic for the handwritten kanji recognition system.
• svg_cache.rs — parsing and caching SVG path data for stroke animations.
• romaji_kana.rs — text conversion from Latin script to kana.

ui (Interface)

Responsible for rendering and handling user input:

• interface.rs — the main application loop (impl eframe::App), screen routing (enum Screen), and layout of all panels.
• settings.rs — the settings window and management of user preferences.
• animator.rs — component for rendering SVG kanji stroke order animations.

Database (core.db)

The application uses a relational SQLite database. Main tables:

1. kanji — core information (id, character, JLPT, grade, strokes).
2. read — kanji readings (on’yomi and kun’yomi).
3. examples — example words and phrases containing the kanji.

The data is joined in Rust via a single large JOIN query at startup and then held in memory for fast search and filtering.

Resources and Asset

Using rust-embed, all static files (DB, JSON, fonts, SVG) are embedded into the binary.

• On the first launch (main.rs -> initialize_app_data), resources are extracted to the user’s system configuration folder:

  • Windows: C:\Users\<Username>\AppData\Roaming\KanjiMaster\
  • Linux: /home/<username>/.config/kanjimaster/
  • macOS: /Users/<Username>/Library/Application Support/KanjiMaster/

• This ensures application autonomy and allows the user to easily reset settings or change localization.