Cheap Tricks for Interaction
This example shows a world map with countries filled in light green, rendered using a natural Earth projection in SVG. It demonstrates simple pan-and-zoom interaction by attaching a `d3.zoom` handler to the SVG, which applies the current zoom transform to a group element containing all country paths. The map loads country boundaries from TopoJSON in the world-atlas package and joins them with names from a TSV file, adding a `<title>` tooltip per country. The code uses `d3.geoPath`, `d3.geoNaturalEarth1`, and `d3.zoom` from D3 v5.