TopoJSON

Next, we will move on to preparing this data relationship for the Web and its spatiotemporal visualization.

TopoJSON is a variant of JSON, which uses the topological relationships between the geometric features to greatly reduce the size of the vector data and thereby improves the browser's rendering performance and reduces the risk of delay due to data transfers.

An example of GeoJSON

The following code is an example of GeoJSON, showing two of our State House Districts. The format is familiar—based on our previous work with JSON—with sets of coordinates that define a polygonal area grouped together. The repeated sections are marked by ellipses (…).

{ "type": "FeatureCollection", "crs": { "type": "name", "properties": { "name": "urn:ogc:def:crs:OGC:1.3:CRS84" ...

Get QGIS: Becoming a GIS Power User now with the O’Reilly learning platform.

O’Reilly members experience books, live events, courses curated by job role, and more from O’Reilly and nearly 200 top publishers.