Calculate sun exposure on a transit trip and find out which side of the bus or train to sit on to avoid the sun.
Live demo: https://evnb.github.io/sunlight-exposure-skeleton
- Enter an origin and destination to get a side-of-vehicle recommendation (left, right, either, or nighttime)
- Preview map showing the route and sun direction at each point along the trip
- Shareable URLs — origin and destination coordinates are saved to the URL automatically
The user enters origin and destination, as well as departure and arrival times for the trip. Sun azimuth is calculated using SunCalc at the origin, destination, and sometimes intermediate points along the route. (Intermediate points are equidistant based on slerp.) The sun azimuth is compared against the route bearing at each point to determine which side of the vehicle the sun will be coming from. The side that appears most often across the route wins.
Geocoding and reverse geocoding are provided by Nominatim (OpenStreetMap data). Maps are rendered with MapLibre GL.
- Svelte 5 + SvelteKit 2 (static adapter)
- Tailwind CSS 4
- Skeleton Labs v4 — sahara dark theme
- Lucide Svelte for icons
npm install
npm run dev
npm run build # production build
npm run preview # preview production build
npm run check # type-checkResources I discovered along the way while working on this project
- SunCalc Library by Volodymyr Agafonkin
- CosineKitty's Astronomy Engine, a library by Don Cross
- suncalc.org tool by Torsten Hoffmann
- suncalc.net tool by Volodymyr Agafonkin
- Nominatim, an Free* and Open Source geocoding service by Sarah Hoffmann
- Photon, a Free* geocoding service by Komoot
- Pelias, an Open Source hostable geocoder
- List of Free Geocoding Services on the Open Street Map Wiki
- Leaflet, an open source JS library for interactive maps
- Open Free Map
- MapLibre, a collection of Open Source mapping libraries
- Iconify.Design, viewer for Open Source icon sets (including emojis)
- Streamline emojis, cute stylized (nonexhausetive) emoji set CC BY 4.0
- Lucide, free beautiful and consistent icons
- Awesome Lists, resource lists about many topics