Gist d5f899183ce045f9ab18fea10c8496bf

Portland parks

The visualization displays the geographic boundaries of parks throughout Portland, Oregon, using a TopoJSON file that encodes each park as a polygon or multipolygon. It renders these shapes on a map-like canvas, showing the distribution and relative sizes of green spaces across the city. The implementation uses D3’s `d3.geoPath` to project and draw the topology, with the data sourced from a gist by Caged. The scene relies on D3’s geographic projection and path generation to convert the TopoJSON arcs into visible, filled polygons.

69% match

Gist 652595e55960a8e04a29

This example visualizes the spatial relationships between metropolitan statistical areas and their constituent counties, townships, and other administrative geometries. The code first builds a combined geometry table using SQL, merging overlapping regions across multiple spatial layers while excluding special cases like Boston. It then renders these shapes using D3.js, likely leveraging `d3.geoPath` for projection and canvas or SVG drawing. The query explicitly handles hierarchical and overlapping geographies, prioritizing township-level detail where available and falling back to county unions for other areas. The final visualization shows how different government boundaries interlock within U.S. metropolitan regions, with the SQL preprocessing ensuring no duplicated or missing polygons.

Gist ea51c362645dc8fb9bdbba440558b37a

Atlas of the United States, using a TopoJSON shapefile rendered with `d3.geoPath` and a custom Albers projection. The map is overlaid with a graticule generated by `d3.geoGraticule`, and states are colored by a choropleth scale. The visualization is drawn on an SVG canvas, and the code uses `d3.json` to load the TopoJSON data and `topojson.feature` to convert it into GeoJSON. A tooltip appears on hover, displaying the state name and value.

CCliffordAnderson

Portland blockgroup TopoJSON

This example visualizes the boundaries of Portland block groups using a TopoJSON file. The map is rendered with D3, which reads the topology and converts it into SVG paths on the fly. The block groups are drawn as distinct polygon features, with each region represented by arcs from the TopoJSON topology. The geographic boundaries are likely derived from Census data, and the visualization highlights the spatial layout of Portland’s neighborhoods at the block-group level. The author, Caged, encoded the TopoJSON structure to share this map, making it easy to reuse for choropleth or interactive map projects. The display emphasizes boundary shapes rather than quantitative values, offering a clean basemap for further analysis.

Gist f18adc0d5e8f2f124288

This visualization combines a GeoJSON geometry collection with a thematic map overlay, using a base point at coordinates (152.5169, -29.8064) and multiple detailed polygon outlines. The polygons appear to trace irregular regions or clusters, likely representing geographic areas or boundaries, while the point marks a specific location. The rendering emphasizes spatial relationships and distributions through geometric shapes, suggesting a geospatial analysis or mapping of regional data.

DDylanFM

Gist 11520211

This example visualizes the geographic boundaries of US states and counties using a TopoJSON file that encodes land, county, and state outlines. Built with D3, it renders the map from the `us.json` TopoJSON data, which contains geometry collections for counties and states. The visualization likely uses D3's projection and path generators to draw the geographic shapes, displaying the boundaries with distinct styling for counties and states. The minimal code structure suggests a basic interactive or static map, with the data provided in a structured TopoJSON format.

67% match

Junction Finding

This example visualizes the topology of the contiguous United States by drawing the mesh of internal boundaries and marking junction points where three or more arcs meet. It uses the TopoJSON library to compute the mesh from the `us.json` topology file, with `d3.geo.path` rendering the SVG paths. Circles are placed at junctions by counting arc endpoints, and the transformation scales coordinates to map space using the topology's transform metadata.

Mmbostock

67% match