GeoJSON feature geometries

June 24, 2020 ยท View on GitHub

Each regulation must be associated with a geographic feature, which must be a line segment (LineString). The geographic coordinates for the points that comprise this feature are contained within the Feature of a Feature Class. The coordinates should be based on the matched SharedStreets output, not the input data. This ensures that the resulting feature geometries have been snapped to the street and can be displayed on a map consistently.

For a primer on GeoJSON terminology and structure, see this post. For a more in depth description the geojson website and the full RFC are good resources.

Each geographic coordinate should have no more than 7 decimal places of precision. This is sufficient to describe a location with ~1.1 cm accuracy. Further precision is unnecessary; less is sufficient.

Field nameImportanceTypeDescriptionExample
typeRequiredstringFeature
geometry.typeRequiredstringDescribes the type of geometry being describedSee here for full list of possible values
geometry.coordinatesRequiredarrayThe coordinates of the geometry being described
geometry.propertiesRequiredjson objectA json object whose members represent the properties of the geojson geometry. They may include but are not limited to; Images, Location, Regulations

Here's an example of the geometry of a GeoJSON feature. Note that the coordinates are for the signpost's location after it was snapped to the street and extrapolated into a street segment:

{
  "type": "Feature",
  "geometry": {
    "type": "LineString",
    "coordinates": [
      [-112.1258855,33.4513431],
      [-112.1253007,33.4513208]
    ],
    "properties": {
    }
  }
}

Examples

The links below show real world curb regulations translated into CurbLR.

LinkDescription
Examples of simple regulationsSimple regulatory scenarios typically involving one or two basic restrictions
Examples of complex regulationsComplex regulatory scenarios typically involving several restrictions
Sample of downtown Portland's parking regulationsContains data for about 3 miles of parking regulations, surveyed in November 2019. This can also be viewed at demo.curblr.org