Spanish municipalities choropleth test with Canvas and preprojected TopoJSON

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Spanish municipalities choropleth test with Canvas and preprojected TopoJSON

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Last edited Feb 1, 2017

Created on Feb 1, 2017

A choropleth map of Spanish municipalities colors each region by population density using a threshold color scale. The visualization renders on a Canvas via `d3.geoPath`, reading preprojected TopoJSON geometry and joining it to CSV population data by municipality ID. A national border is stroked afterward for context. The map uses a forked `d3-geo-projection` pipeline to streamline drawing performance.

AI-generated description

Example using a preprojected topojson based on es-atlas by Martín González. For now using a d3-geo-projection forked version by Roger Veciana.

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