Day 37. Populated places by size and rank 🌐
How visualize global settlement patterns without political boundaries dictating story?
Circle size = population, brightness = rank. Removes borders. Settlement structure visible on own terms.
D3.js canvas rendering handles thousands of points. City selection uses quadtree spatial index.
Data: Natural Earth. Quadtree inspired by Alain Roan (Observable).
https://maptheclouds.com/playground/30-day-map-challenge/points/