TopoJSON (Topology JavaScript Object Notation) Writer Parameters
Formatting Parameters
Formatting Type
The formatting of the output JSON file.
- Linear: The entire JSON document is output on one line. This option produces the smallest possible JSON files.
- Pretty Print: The JSON document will contain additional whitespace characters, making it much more human-readable.
Indent Size
This parameter controls the indentation style in the JSON document, and is enabled when Formatting Type is Pretty Print. The indentation style can use either tab characters, or a variable number of space characters.

Quantization removes information by reducing the precision of each coordinate. The writer will use the value of this parameter to limit the range of the coordinates.
The default value is 100000, which is relatively accurate for grids of size up to 10000 x 10000. A smaller quantization value can reduce the size of the output file when writing out a large number of coordinates, at the cost of the precision and accuracy of the coordinates. See more information: https://stackoverflow.com/questions/18900022/topojson-quantization-vs-simplification.

By default, the GeoJSON writer will reproject all features to the WGS84/EPSG:4326 coordinate system.
Setting this parameter to No will disable this automatic reprojection, and feature geometries will be written in the coordinate system they had when arriving at the writer.
Features with no coordinate system will be assumed to already be in the WGS84 coordinate system.

Setting this parameter to No (the default) will disable writing the optional Bounding Box object.