TATE — Vertical Writing Mode for Obsidian

An Obsidian plugin that brings authentic vertical writing (縦書き) to your notes. Renders and edits Japanese text in the traditional top-to-bottom, right-to-left layout — with smooth editing even on files with over a million characters.

日本語版 README はこちら

Features

Ruby, Tate-chu-yoko, Emphasis Marks, and Headings via Aozora Notation

The plugin supports the annotation syntax used by Aozora Bunko, a digital library of Japanese literature.

Notation	Renders as
｜東京《とうきょう》 or 東京《とうきょう》 (consecutive kanji)	Ruby (furigana)
２０２５［＃「２０２５」は縦中横］	Tate-chu-yoko (digits/latin rotated upright)
春［＃「春」に傍点］	Emphasis dots (sesame marks)
序章［＃「序章」は大見出し］	Large heading (bold, 1.3×)
第一節［＃「第一節」は中見出し］	Mid heading (bold, 1.2×)
はじめに［＃「はじめに」は小見出し］	Small heading (bold, 1.1×)

Applying via Command Palette

Select text, open the command palette (Ctrl+P / Cmd+P), and run one of:

• Add ruby to selection (ruby)
• Make selection tate-chu-yoko (tate-chu-yoko: tcy)
• Add emphasis marks to selection (bouten)
• 選択テキストを大見出しに設定
• 選択テキストを中見出しに設定
• 選択テキストを小見出しに設定

All annotations are applied to the selected text range.

Inline Editing

Moving the cursor into a ruby, tate-chu-yoko, emphasis mark, or heading element expands it into raw Aozora text in place — the same behavior as Obsidian's Markdown editor. Moving the cursor out collapses it back to the rendered form. Pressing Enter while an element is expanded also collapses it immediately.

Live Conversion

Typing an Aozora annotation in full and closing it with 》 (ruby) or ］ (tcy, bouten, headings) converts the notation to its rendered form on the spot, without using the command palette.

Auto-indent and Typography Helpers

Four independent settings refine how text is entered in the vertical view. All of them write actual full-width space characters (U+3000) into the file — not just visual CSS indentation.

Setting	What it does
Convert half-width space to full-width	Replaces a typed half-width space (Space key) with a full-width space 　. Applies everywhere except paste.
Auto-indent on input	Inserts one full-width space at the start of a line when a character is typed there (covers both direct input and Japanese IME).
Match preceding paragraph indent	When Enter is pressed to start a new paragraph, automatically inserts the same number of leading full-width spaces as the preceding paragraph. Works independently of the setting above.
Remove bracket indent	When a full-width opening bracket (「『（ etc.) is typed after leading spaces, removes one leading space — following traditional Japanese typography where brackets are not indented.

All four are on by default.

Line-break Rules (Kinsoku)

Controls which characters are forbidden at the start or end of a line (punctuation, brackets, etc.) via the CSS line-break property.

Rule	Description
Normal	Standard kinsoku rules (default)
Strict	Strictest — small kana (っ, ゅ, etc.) are also kept from line starts
Loose	Newspaper style — relaxed rules that favor tighter wrapping
Anywhere	No restrictions — break anywhere

Incremental Search and Replace

Open the search panel from the command palette:

• 検索 (search) — opens the panel with the search field focused.
• 置換 (replace) — opens the panel with the replace field expanded and focused.

As you type in the search field, all matches are highlighted instantly and the nearest hit at or after your cursor position is focused. Use the ▶/▼ toggle button at the left of the panel to show or hide the replace field.

Search field focused

Action	Key / Button
Next hit	Enter or ↓ button
Previous hit	Shift+Enter or ↑ button
Close panel	Esc or × button

Replace field focused

Action	Key / Button
Replace current hit and move to next	Enter or 置換 button
Replace all hits at once	全置換 button
Close panel	Esc

Tab moves focus from the search field to the replace field (and back).

When a match partially overlaps a ruby, tate-chu-yoko, emphasis mark, or heading annotation, the annotation is stripped and only the unmatched portion of the base text is preserved as plain text.

Closing the panel restores the cursor to the last navigated hit, or to the position it was at when the panel was opened if no navigation occurred.

Heading Outline Panel

The outline panel lists all heading annotations in the current file in a dedicated sidebar and lets you jump to any heading with a single click.

Opening the panel

• Run アウトラインパネルを開く from the command palette (only available while the vertical writing view is open).
• Or click the tally-3 icon (☰) in the vertical writing view's toolbar.

Navigation

Click any entry to move the cursor to that heading and bring the vertical writing view to the front.

• Large headings are shown at the leftmost indent level (bold).
• Mid headings are indented one level.
• Small headings are indented two levels.

Live updates

The outline refreshes automatically whenever the file content changes. It clears when the vertical writing view is closed.

Other Features

• Bidirectional real-time sync: Edits and Undo/Redo operations stay in sync with the Obsidian Markdown view in real time.
• Character count in the status bar: The character count (excluding Aozora notation) is displayed in the Obsidian status bar.
• Smooth editing on large files: Input and Undo/Redo remain responsive even on large files. (On very large files there may be a brief lag before editing becomes available after the file finishes loading.)
• Cursor position persistence: The cursor position is saved when a file is closed and automatically restored the next time it is opened.

Installation (from source)

1. Clone the repository and build:

git clone https://github.com/nekoe/obsidian-tate
cd obsidian-tate
npm install
npm run build

2. Copy the build output to your Obsidian plugins folder:

cp main.js manifest.json styles.css {YOUR_VAULT_PATH}/.obsidian/plugins/tate/

3. Enable the plugin in Obsidian under Settings → Community Plugins.

Usage

• Run 縦書きビューを開く from the command palette (Ctrl+P / Cmd+P).
• The view opens as a tab and automatically loads the active file.
• Edits are kept in sync with the underlying Obsidian file in both directions.

Known Limitations

• Cursor jump near ruby elements on macOS older than 26: On macOS versions earlier than 26, pressing the left or right arrow key while the cursor is in a paragraph containing ruby elements may cause the cursor to jump unexpectedly.
• IME input after emphasis marks: When the cursor is placed immediately after an emphasis mark (bouten) and text is entered via IME, the composition text temporarily appears with sesame marks applied. The marks disappear once the IME input is confirmed.
• Deletion at ruby/tate-chu-yoko boundaries: Pressing Delete or Backspace with the cursor placed at the very start or end of a ruby or tate-chu-yoko element does not delete the adjacent character. To delete, either select the text first, or expand the element inline and delete from within.
• Consecutive Aozora notation input: Typing one Aozora notation immediately after another may cause the second notation to be inserted incorrectly or cursor movement to behave unexpectedly.
• Typing into a line-initial Aozora element: When an Aozora notation element appears at the very start of a line, placing the cursor at the line beginning triggers its inline expansion automatically. Any characters typed while expanded are inserted inside the element, but once it collapses they are treated as plain text.

Settings

Configure under Settings → TATE:

Setting	Description	Default
Font family	Font used in the vertical view (CSS font-family syntax)	Hiragino Mincho ProN
Font size	Font size in the vertical view (px)	22
Convert half-width space to full-width	Replace typed space with full-width space	On
Auto-indent on input	Insert one 　 at line start when a character is typed	On
Match preceding paragraph indent	On Enter, copy the indent of the paragraph above	On
Remove bracket indent	Remove one leading 　 when a full-width bracket is typed after spaces	On
Line-break rule	Kinsoku rule set for line start/end restrictions	Normal
Suppress ruby inline expansion	Do not expand ruby when cursor enters it (Experimental)	Off
Suppress tcy inline expansion	Do not expand tate-chu-yoko when cursor enters it (Experimental)	Off
Suppress bouten inline expansion	Do not expand emphasis marks when cursor enters them (Experimental)	Off
Suppress heading inline expansion	Do not expand headings when cursor enters them (Experimental)	Off