{"version":"1.0","type":"rich","title":"Visualizing Population Centers","description":"This visualization displays world population density through colored contour layers on a Natural Earth projection map. City population data from the Simplemaps World Cities Database is weighted to compute density contours using `d3.contourDensity`. Colors interpolate between `interpolateCubehelixDefault` and `interpolateReds` based on density values, rendered via `d3.geoPath` with land clipping. The map supports zooming through `d3.zoom` and includes city labels for populations above seven million.","provider_name":"VizHub AI Studio","provider_url":"https://vizhub.com","html":"<iframe src=\"https://vizhub.com/viz/f8ff684d310c40c9a7776980626d83d6?mode=embed\" width=\"960\" height=\"500\" scrolling=\"no\" frameborder=\"0\"></iframe>","width":960,"height":500,"cache_age":3600}