Points on a Map
This map visualization displays the global distribution of cities, with points sized according to population using a square root scale to encode area proportionally. The geographic context is rendered using D3’s `geoNaturalEarth1` projection, with landmasses, graticules, and country interiors drawn via `geoPath`. City data, loaded from a CSV via `d3.csv`, is plotted as semi-transparent circles, and population values are scaled using `d3.scaleSqrt` to ensure visual accuracy. The visualization is built with React, leveraging the `useWorldAtlas` and `useCities` hooks to asynchronously fetch and process TopoJSON and CSV data.