Egatari components

日本語

Animated figures (Web Components) for Egatari Studio: bars that grow step by step, flow diagrams that assemble, curves drawn one by one, kanbun read in order, and more. Studio builds them into Egatari lessons (format): one HTML file that plays offline.

The list is in CATALOG.md. Each component lives in components/<name>/:

File	What it is
index.js	the custom element <m-<name>> (it follows Studio's component contract)
README.md	frontmatter (name, version, series, tier (and set), summary, steps, props) and how to use it
demo.html	a 1–2 slide sample deck

Using them

You do not install anything from here. Each Studio release carries a copy of the components it was tested with (vendor/components/<name>/<version>/, pinned in components.lock.json). Studio maintainers bring in a new release with

npm run components:update -- v1.0.0

which downloads the release tarball, checks it against manifest.json and keeps every version it has ever brought in, so that a lesson built with an older version can still be rebuilt exactly.

Releases and versions

• A release is a tag vX.Y.Z with two assets: egatari-components-vX.Y.Z.tar.gz (every component's files and LICENSE) and manifest.json (name, version, the SHA-256 of the tarball, and the SHA-256 of every file, including each index.js). The release notes repeat the tarball's SHA-256. The tarball's hash is byte-exact; the per-file hashes are identity hashes as in spec §6: for text files, CRLF and lone CR become LF and a leading UTF-8 BOM is removed before hashing, so a checkout on any system gives the same hash. Files are stored with LF.
• Yanked releases. A release may be withdrawn (for example after a security fix). It stays available; the newest release's manifest.json lists it under yanked with the replacement version, a reason and a date. From 2.0, a single part's version may be withdrawn the same way: the part's entry lists it under withdrawn (SECURITY.md). Editors offer a rebuild and never substitute silently (spec §6).
• Tags are never moved or reused. A fix is a new version.
• An Egatari file records each registry component as {name, version, sha256}, where sha256 covers index.js only (spec §6). Changing a component's index.js (other than its line endings) changes its hash, so editors can tell which version a lesson needs.
• Version numbers: a change that can alter how an existing lesson looks (layout, timing, steps) is a minor or major version; a major version also breaks the data a lesson writes.

How a release is made: RELEASING.md.

Proposing a component

Open a proposal issue. It asks for an example, the lesson you used it in, a draft of the data, the final state, why inline SVG with Studio's motion primitives is not enough, the rights to everything in it, what must stay readable when static, and where else it would help. The maintainer decides the name at that stage. Details: CONTRIBUTING.md.

Bugs in a component: bug report. Bugs in the editor, the build or a deck go to Egatari Studio.

Tests

npm test

Node 22 or later and Chrome, Edge or Playwright's Chromium. The tests build every demo with a pinned commit of Egatari Studio (tools/studio.json: a full commit sha, now 03eaf06 on Studio's main); the first run fetches exactly that commit into .studio/ and runs npm ci there (the only network access). They run Studio's own checker (kit/check.mjs) on every demo: no errors (warnings are listed). They also scan component code for eval-like code (tools/scan-code.mjs) and test the expression evaluator of m-sweep and m-curves (tools/test-expr.mjs). They check, for each demo: no console errors, a screenshot of each step (mid-motion and final), determinism (the same position draws the same pixels after jumping elsewhere and back), text at least 24 px, no overlapping text or text outside the slide; and that wrong-shaped data shows an inline placeholder instead of throwing. CI runs them on Linux, macOS and Windows.

Security

Components never run a lesson's data as code; m-sweep and m-curves evaluate their formulas with a small arithmetic parser. Grammar, audit and how to report a vulnerability: SECURITY.md.

History

These components were developed inside Egatari Studio (formerly motion-academic-slides) and moved here with their history in October 2026; v1.0.0 is byte-identical to components/ in Studio v0.4.3 (commit 8419183).

License

MIT, the same as Egatari Studio. The demos' texts are the authors' own, public domain (classical Chinese and Japanese texts) or fictional (company names and numbers).

One exception: components/kakijun/index.js contains an OFL-1.1 data block (kana stroke shapes derived from strokesvg (Klee One), between /*@egatari-block strokes*/ and /*@egatari-block-end*/), so that part is MIT AND OFL-1.1; see components/kakijun/OFL.txt and NOTICE.