# Focus Room Big Sign

> Make text as big as the screen allows: a sign as SVG, PNG and printable PDF. Fits your text — a word, a sentence or a few lines — into a full-screen sign: the largest font size at which it still fits with a margin, measured with the real Noto font metrics (Latin, Cyrillic, Greek, Arabic, Devanagari and common Chinese, Japanese and Korean characters). You get an SVG with the letters as outlines, a PNG for a TV, tablet or video call, an A4 landscape PDF to print and a link that opens the sign full screen in Focus Room, where it can also scroll as a marquee.

Part of usefulweb.app (https://usefulweb.app/). Part of [Focus Room](https://focusroom.usefulweb.app/) (ownerApp: focusroom). Results are deterministic calculations from the inputs and the listed assumptions; the API returns exactly what the web page shows.

## Use it
- Human interface: https://focusroombigsign.usefulweb.app/ (interactive tool at https://focusroombigsign.usefulweb.app/tool)
- JSON API: POST https://focusroombigsign.usefulweb.app/api/v1/calculate with a JSON object of inputs (schema: https://focusroombigsign.usefulweb.app/api/v1/tool)
- OpenAPI: https://focusroombigsign.usefulweb.app/openapi.json
- MCP (Streamable HTTP): https://focusroombigsign.usefulweb.app/mcp - tool `focusroom_big_sign`

## Inputs
- text (textarea): Text - Line breaks are kept; long lines are wrapped at spaces. At most 280 characters.
- theme (select): Colours
- size (select): Picture size
- marquee (boolean): Scroll as a marquee in the app - Only the app link scrolls; the files show the fitted sign.

## Method
- The text is shaped with the Noto fonts (Lumina’s OpenType shaper: Arabic joining, Devanagari reordering, kerning) and measured exactly. A binary search finds the largest font size at which the greedy word wrap fits inside the picture minus a 6 % margin, with a line height of 1.18 em and at most 8 lines; your own line breaks are kept.
- The SVG contains the glyph outlines as paths (quadratic TrueType curves), so it looks the same on any device. The PNG is drawn by Printshop’s scanline rasteriser (non-zero winding, four sub-scanlines) and the PDF is a vector file with the font embedded as a subset — both from the same display list.
- Each colour pair has a contrast ratio of at least 7:1.