Circular Distance Map

I’ve been playing around with map visualisations a fair bit again recently, both using JS libraries like D3.js for interactive ones, and the R Project for non-interactive static ones. I’ve also been using LLM/AI agents a bit for help - especially with R, which I have no previous experience with (and LLMs being pretty good at ‘gathering’ information from various manpages and examples in their training data). I had previously implemented a basic interactive globe visualisation with Three.js showing Great Circle Routes between a limited set of airports, and I was keen to try something along the same lines of showing Great Circle Routes on a globe (with the distance of each plotted visually next to each route this time), but with better map fidelity, in particular with vector drawing of shapefiles rather than with raster textures as I’d previously done) while also allowing some styling. I also experimented with highlighting the distance from a location with distance rings, which is also…