Adaptive resampling recursively subdivides input polygons, applying the Douglas–Peucker perpendicular distance check to determine whether additional samples are needed. The animation cycles through eight stages, starting with a red equator as a polyline of five coordinates and progressively refining it through resampling. Each stage shows the projected resampled points, with black circles and lines highlighting newly inserted samples and their original positions. The example uses d3.geo.equirectangular, d3.geo.interpolate, and d3.geo.path, rendering with SVG and transitions, and demonstrates the adaptive subdivision of a geographic line on a graticule sphere.