# robb0wen/tornis

Tornis helps you watch and respond to changes in your browser's viewport 🌲

Repository: https://github.com/robb0wen/tornis
Canonical: https://ross.abutalabs.com/products/tornis
Homepage: https://tornis.robbowen.digital
Language: JavaScript
License: MIT
License Family: permissive
Last push: 2023-01-06T01:50:48+00:00

## Health v2 (maintenance only)
Score: 32/100 (v2, computed 2026-09-03T02:20:16.233290+00:00)
- activity 0, release rhythm 35, longevity 100
- inputs: {"age_days": 2666, "days_push": 1336, "days_rel": null, "gap_med": null, "n_releases_24m": 0}
- flags: no_releases
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 1591, forks 35 (observed 2026-08-28T04:05:08.626220+00:00)

## What it is
Tornis is a minimal JavaScript library that watches and tracks the state of the browser's viewport, including mouse position, scroll position and velocity, viewport size, and device orientation. It uses a throttled, requestAnimationFrame-based store so subscribed functions only run when values change and the browser is ready to render.

## Use cases
- track scroll position and velocity in the browser
- react to mouse cursor movement and velocity
- create parallax and scroll-driven effects
- monitor viewport size changes on resize
- track device orientation and pixel ratio
- optimize scroll/resize handlers for render performance

## When to choose
- you need combined viewport state (scroll, mouse, size) in one store
- you want performant, throttled viewport tracking instead of raw event handlers
- you're building scroll- or cursor-driven visual effects in vanilla JS

## When to avoid
- you need a full parallax library with built-in effects
- you're working in a framework with its own reactive state system
- you need server-side or non-browser viewport tracking

## Facets
- artifact type: library
- maturity: maintenance
- function: state-management, developer-tools
- domain: frontend, web-development, browser-extensions
- platform: browser
- tags: viewport-tracking, scroll-velocity, mouse-position, requestanimationframe, performance-optimization, javascript

## Member repositories
- robb0wen/tornis (main) score 32

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:05:08.626220+00:00.
- Health v2: computed from the inputs above; adoption is never an input.
- Inferred fields (summary, facets, guidance): AI-extracted, prompt v1, taxonomy v1, on 2026-08-30T03:54:45.639314+00:00, confidence not recorded.
  - readme: https://github.com/robb0wen/tornis (fetched 2026-08-28T04:05:08.626220+00:00, sha 548288c5d5b9)
  - homepage: https://tornis.robbowen.digital (fetched 2026-08-29T11:25:36.068187+00:00, sha adfd566ff667)
- Data as of 2026-08-30T08:39:29.467469+00:00.