# Glossary

## Link GeoJSON Back to Top

Terraformer uses the GeoJSON specification as a guide on how to format all representation of geographical data.

### Link Coordinate Back to Top

A coordinate is the building block for the rest of the GeoJSON specification. It is represented by an array of `x`, `y` integers. The ordering of `x` and `y` are important, this means that when representing latitude and longitiude the order is `[longitude, latitude]`.

    [-122.680, 45.528]

GeoJSON Coordinate

### Link Coordinates Back to Top

An array of Coordinate objects that are used to define a line or polygon.

    [
      [-122.680, 45.58],
      [-123.230, 45.62],
      [-122.80, 45.22]
    ]

GeoJSON Coordinate

### Link Bbox Back to Top

A GeoJSON bounding box is usually a 4-item array representing the rectangle that will contain the GeoJSON object.

    [-122.70, 45.51, -122.64, 45.53]

GeoJSON BBox

### Link Geometry Back to Top

“GeoJSON Geometry” refers to any of the single geometry objects from the geoJSON specification like Point, MultiPoint, LineString, MultiLineString, Polygon, or MultiPolygon.

GeoJSON Geometry

### Link Point Back to Top

An object representing a single point.

    {
      "type": "Point",
      "coordinates": [-105.01621, 39.57422]
    }

GeoJSON Point

### Link MultiPoint Back to Top

An object representing multiple points as a single coordinate array.

    {
      "type": "MultiPoint",
      "coordinates": [ [-105.01, 39.57], [-80.66, 35.05] ]
    }

GeoJSON MultiPoint

### Link LineString Back to Top

A series of coordinates that form a line.

    {
      "type": "LineString",
      "coordinates": [
        [-101.5, 39.662],
        [-101.75, 39.2415],
        [-101.64, 39.2415],
      ]
    }

GeoJSON LineString

### Link MultiLineString Back to Top

An object that represents multiple linestrings in a single object.

    {
      "type": "MultiLineString",
      "coordinates": [
        [
          [-101.5, 39.662],
          [-101.75, 39.2415],
          [-101.23, 39.2415],
          [-101.749, 39.7984],
          [-101.5, 39.011]
        ],[
          [-99.23, 38.6605],
          [-99.56, 38.727],
          [-99.25, 38.018]
        ],[
          [-98.499, 38.913],
          [-98.499, 38.913],
          [-98.38, 38.15],
          [-97.5, 38.629]
        ]
      ]
    }

GeoJSON MultiLineString

### Link Polygon Back to Top

An array of coordinates defining a polygon.

    {
      "type": "Polygon",
      "coordinates": [
        [ [41.83, 71.01], [56.95, 33.75], [21.79, 36.56], [41.83, 71.01] ]
      ]
    }

GeoJSON Polygon

### Link MultiPolygon Back to Top

An object that represents multiple polygons in a single object.

    {
      "type": "MultiPolygon",
      "coordinates": [
        [
          [ [102.0, 2.0], [103.0, 2.0], [103.0, 3.0], [102.0, 3.0], [102.0, 2.0] ]
        ],
        [
          [ [100.0, 0.0], [101.0, 0.0], [101.0, 1.0], [100.0, 1.0], [100.0, 0.0] ]
        ]
      ]
    }

GeoJSON MultiPolygon

### Link Feature Back to Top

GeoJSON Features combine a Geometry object with a unique identifier and set of metadata.

    {
      "type": "Feature",
      "id": "stadium",
      "geometry": {
        "type": "Point",
        "coordinates": [-104.99404, 39.75621]
      },
      "properties": {
        "name": "Coors Field",
        "amenity": "Baseball Stadium",
        "popupContent": "This is where the Rockies play!"
      }
    }

Feature

### Link FeatureCollection Back to Top

Contains multiple Features objects in a single object.

    {
      "type": "FeatureCollection",
      "features": [
        {
          "type": "Feature",
          "geometry": {
            "type": "Point",
            "coordinates": [-80.83775386582222, 35.24980190252168]
          },
          "properties": {
            "name": "DOUBLE OAKS CENTER",
            "address": "1326 WOODWARD AV"
          }
        },
        {
          "type": "Feature",
          "geometry": {
            "type": "Point",
            "coordinates": [-80.83827000459532, 35.25674709224663]
          },
          "properties": {
            "name": "DOUBLE OAKS NEIGHBORHOOD PARK",
            "address": "2605  DOUBLE OAKS RD"
          }
        }
      ]
    }

FeatureCollection

### Link GeometryCollection Back to Top

Contains multiple Geometry objects in a single object.

    {
      "type": "GeometryCollection",
      "geometries": [{
        "type": "Polygon",
        "coordinates": [
          [ [41.83, 71.01], [56.95, 33.75], [21.79, 36.56], [41.83, 71.01] ]
        ]
        },{
          "type": "MultiPoint",
          "coordinates": [ [100, 0], [45, -122] ]
        }
      ]
    }

GeometryCollection

## Link Terraformer Primitives Back to Top

Terraformer Primitives wrap their GeoJSON counterparts to provide extra functionality.

### Link Point Primitive Back to Top

An object respresenting a GeoJSON Point

Point

### Link MultiPoint Primitive Back to Top

An object respresenting a GeoJSON MultiPoint

MultiPoint

### Link LineString Primitive Back to Top

An object respresenting a GeoJSON LineString

LineString

### Link MultiLineString Primitive Back to Top

An object respresenting a GeoJSON MultiLineString

MultiLineString

### Link Polygon Primitive Back to Top

An object respresenting a GeoJSON Polygon

Polygon

### Link MultiPolygon Primitive Back to Top

An object respresenting a GeoJSON MultiPolygon

MultiPolygon

### Link Feature Primitive Back to Top

An object respresenting a GeoJSON Feature

Feature

### Link FeatureCollection Primitive Back to Top

An object respresenting a GeoJSON FeatureCollection

FeatureCollection

### Link GeometryCollection Primitive Back to Top

An object respresenting a GeoJSON GeometryCollection

GeometryCollection

### Link Circle Primitive Back to Top

An object representing a GeoJSON Feature which contains a polygonal representation of a circle.

Circle

## Link Misc Back to Top

### Link Envelope Back to Top

Envelopes are a common structure for indexes like Terraformer.RTree.

    {
      x: 1,
      y: 1,
      w: 15
      h: 15
    }

### Link Convex Hull Back to Top

Convex

    {
      x: 1,
      y: 1,
      w: 15
      h: 15
    }