Danila Poyarkov d91e6a36d9 Fix code formatting across all docs

- Wrap all enum values in backticks (FRAME, SOLID, ROUND, etc.)
- Fix single-backtick code blocks → triple backticks in node-types, scene-graph
- Replace ASCII diagrams with mermaid in file-format
- Delete stale mcp-tools.md and eval-command.md from all locales
- Update dead links: /reference/mcp-tools → /programmable/mcp-server,
  /eval-command → /programmable/cli/scripting

2026-03-08 13:53:33 +03:00

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File Format

.fig File Structure

A .fig file is a ZIP archive containing a Kiwi-encoded binary message:

block-beta
  columns 1
  A["Magic header: <code>fig-kiwi</code> (8 bytes)"]
  B["Version (4 bytes, uint32 LE)"]
  C["Schema length (4 bytes, uint32 LE)"]
  D["Compressed Kiwi schema"]
  E["Message length (4 bytes, uint32 LE)"]
  F["Compressed Kiwi message — NodeChange[]"]
  G["Blob data — images, vector networks, fonts"]

Import Pipeline

flowchart LR
  A[".fig file"] --> B["Parse header"]
  B --> C["Decompress Zstd"]
  C --> D["Decode Kiwi schema"]
  D --> E["Decode message"]
  E --> F["NodeChange[]"]
  F --> G["Build SceneGraph"]
  G --> H["Resolve blob refs"]
  H --> I["Render"]

Export Pipeline

flowchart LR
  A["SceneGraph"] --> B["NodeChange[]"]
  B --> C["Kiwi encode"]
  C --> D["Compress"]
  D --> E["Build ZIP"]
  E --> F[".fig file"]

Export uses ⌘S (Save) and ⇧⌘S (Save As) with native OS dialogs on the desktop app. The exported file includes a thumbnail.png required by Figma for file preview.

Compression uses Zstd via Tauri Rust command on desktop, with deflate fallback in the browser.

Kiwi Binary Codec

The codec handles Figma's 194-definition Kiwi schema with NodeChange as the central type (~390 fields). Key components:

Module	Purpose
`kiwi-schema`	Kiwi parser (from evanw/kiwi), patched for ESM and sparse field IDs
`codec.ts`	Encode/decode messages using the Kiwi schema
`protocol.ts`	Wire format parsing and message type detection
`schema.ts`	194 message/enum/struct definitions

Sparse Field IDs

Figma's schema uses non-contiguous field IDs (e.g. 1, 2, 5, 10 with gaps). The kiwi-schema parser handles this correctly.

Compression

.fig files use Zstd compression for both the schema and message payloads. Decompression uses the fzstd library. For export, Zstd compression is offloaded to a Tauri Rust command on the desktop app (better performance, correct frame headers). In the browser, deflate via fflate is used as a fallback.

Supported Formats

Format	Import	Export
`.fig` (Figma)	✅	✅
`.svg`	Planned	Planned
`.png`	Planned	Planned
`.pdf`	—	Planned

Clipboard Format

Copy/paste uses the same Kiwi binary encoding:

flowchart LR
  subgraph Copy
    A["Selected nodes"] --> B["Encode NodeChange[]"]
    B --> C["Compress"]
    C --> D["Clipboard<br/><code>application/x-figma-design</code>"]
  end
  subgraph Paste
    D --> E["Decompress"]
    E --> F["Decode Kiwi"]
    F --> G["Create nodes"]
  end

This enables bidirectional clipboard between OpenPencil and Figma.

2.8 KiB Raw Blame History