TextGraph for Markdown Preview

Report all TextGraph issues on GitHub → Use this shared tracker for extension bugs, rendering problems, feature requests, and documentation issues.

Render textgraph fenced code blocks as diagrams in VS Code’s built-in Markdown preview. Diagrams update automatically as you edit, including unsaved changes. Multiple diagrams, ordinary Markdown, and inline errors work together.

# A small workflow

```textgraph
Start -> Review -> Done
```

Open a Markdown file, then run Markdown: Open Preview to the Side (Ctrl+K V, or Cmd+K V on macOS). The first diagram takes a few seconds to initialize.

Requirements

• VS Code 1.101.0 or newer, desktop or a Node-based remote Extension Host. VS Code 1.101 introduced Node 22 in both desktop and remote hosts. A browser-only host such as vscode.dev without a remote host is unsupported.
• A trusted workspace to render. Restricted Mode displays escaped source with a trust notice and does not start the renderer.

Independent of the DrawMotive drawing editor. Uses public @drawmotive/textgraph@0.2.0, bundled with its runtime and fonts. Rendering is local; no service, API key, separate npm installation, or private C#/WASM build is needed.

Errors and limits

SDK syntax diagnostics appear beside the source. Editing triggers a new render. SDK 0.2.0 renders inline groups including A -> {} and A -> {{x}}. Each render has a 15-second deadline and the Worker is terminated on timeout. Other diagrams continue in a fresh Worker. A timeout is an operational error, not a syntax diagnosis.

Each diagram is limited to 64 KiB of source and a maximum width of 2048 pixels. Complex diagrams may hit the deadline. Bundled SDK fonts determine available glyphs; custom font packs are not yet configurable.

Security and lifecycle

The preview receives PNG data URIs and escaped diagnostic text. No preview JavaScript, browser Worker, external server, or CSP relaxation is needed. Workspace source is SDK input; never executable JavaScript.

Changed or removed diagrams cancel obsolete work. Closing a document releases its cache. The Worker shuts down after ten idle seconds; inactive caches expire after five minutes because the Markdown extension has no public preview-close event. Deactivation terminates outstanding work.

Install a VSIX

Run Extensions: Install from VSIX… and select textgraph-markdown-0.2.0.vsix, or:

code --install-extension textgraph-markdown-0.2.0.vsix

Development

From this repository’s independent vscode npm package:

npm ci --workspaces=false
npm test
npm run package
npm run test:host

The host test downloads VS Code 1.101.0, installs the actual VSIX into isolated profiles, and tests built-in Markdown Preview through the real Extension Host and webview. Linux CI uses xvfb-run -a npm run test:host; a desktop display also works. Set VSCODE_VERSION=stable for the current stable host. No C# project is built.

See the project repository and the SDK.