heatmap-tiles

A service to general a global heatmap of cycling data. 🚴 🚴 🚴

This service generates the data behind the map that is then generate by the Mapbox GL JS heatmap layer. A demo is available here.

How does this work?

This service keeps a tiny heatmap per user and updates those track-by-track. Then it uses those user-heatmaps to update the global heatmap.

1. Take the new unprocessed tracks.
   a. Update the heatmaps of the users of those tracks.
   b. Keep the tile numbers at zoom level 14 that were modified while doing this.
2. Update the global heatmap
   a. Rebuild the zoom level 14 modified tiles by:
   1. Adding up all data of all heatmaps of all users in the tile.
   2. Exclude all pixels where we have less than n users.
      b. Update the higher zoom levels by rebuilding the modified tiles.