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Show HN: 3D Terrain simulation for hiking, skiing etc.
Home for all your GPS Tracks: Visualize, share and manage your GPS tracks. - r-follador/CubeTrek
The actual 3D magic is performed by the awesome Babylon.js library (check it out, if you've never heard of it), the graph is handled by D3.js (very versatile, but a steep learning curve), the 2D map is rendered with MapLibre GL JS (which is very straightforward to use in this particular case). So here's what happens when you upload a FIT or GPX file: the server reads the tracks, downsamples them to a reasonable resolution and calculates some descriptive values (such as the geographical bounding box, distance, time, etc.). This makes the number of displayed coordinates on the user device more manageable, with the downside of noticeably simplified tracks when completely zoomed in.
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