Open-source JTD rendering engine and editor project for Ichitaro documents (.jtd, .jtt, and .jttc).

OpenJTD aims to become an open-source JTD rendering engine and editor. The current phase focuses on rjtd, a Rust toolset that builds the components needed to get there: container inspection, text extraction, document modeling, export, and viewer integration. The longer-term technical milestone is a practical JTD engine that can support faithful layout rendering and editing.

• CFB/OLE container inventory for .jtd, .jtt, and .jttc files, including lenient fallback handling for malformed files.
• Text extraction from observed /DocumentText streams.
• Observed .jttc JustCompressedDocument and -lh5- payload support.
• Embedded SsmgV.01 / TextV.01 fragment recovery for files without a named /DocumentText stream.
• Minimal Document Model output as plain text, Markdown, JSON, and text-oriented PDF.
• Diagnostic parsers for /DocumentTextPositionTables, /LineMark, /PageMark, /PaperMark, and object/control marker research.
• WASM wrapper support used by early viewer integration experiments.

cd rjtd
cargo test --workspace

cargo run -p rjtd-cli -- info path/to/document.jtd
cargo run -p rjtd-cli -- cat path/to/document.jtd
cargo run -p rjtd-cli -- export path/to/document.jtd --format md
cargo run -p rjtd-cli -- export path/to/document.jtd --format json
cargo run -p rjtd-cli -- export path/to/document.jtd --format pdf -o output.pdf

To refresh the local sample PDF artifacts used for visual regression checks, run this from the repository root:

scripts/regenerate-pdf-output.sh

• rjtd/ - Rust toolset and workspace for the current OpenJTD components: core engine, CLI, exporters, WASM wrapper, and test helpers.
• openjtd-spec/ - public specification notes and RFC records.
• docs/ - charter, architecture, roadmap, and research policy.
• openjtd-samples/ - redistributable sample/output artifacts.
• rjtd-testdata/ - test fixtures.
• openjtd.github.io/ - future project site.

• rjtd/README.md describes the rjtd Rust workspace, CLI, exporter, and diagnostic command surface.
• openjtd-spec/README.md indexes the specification work and RFC process.
• docs/CHARTER.md, docs/ARCHITECTURE.md, and docs/ROADMAP.md explain the project direction.

OpenJTD's repository layout and engine boundaries take inspiration from the rhwp project structure, adapted for JTD.

OpenJTD is in the reverse-engineering and component-building stage. It is not yet a complete JTD rendering engine or editor, and the rjtd APIs, data model, and diagnostic commands may still change.

Text extraction works for observed files, but full paragraph semantics, layout fidelity, styles, tables, ruby annotations, images, and native editing behavior are incomplete. PDF and SVG output should be treated as text-oriented fallback output, not native layout reproduction.

English is the default documentation language. Japanese translations use *.ja.md.