Rule One: Judgement on File Format

Judge whether the file is a compilable JSON file. If it is, the data structure will be verified. If not, you need to select and upload the file again with a prompt indicating that the GeoJSON file cannot be compiled.

Rule Two: Completeness of Geometric Types' Attributes

Detect whether there are fields which can provide the attributes of geometric types like building, road, grass, water, and calder:bbox in each Feature.

Rule Three: Compliance of Geometry Attribute in a Feature

Geometric types like building, road, grass, water, and calder:bbox in a Feature need to correspond with their Geometry attributes accordingly. For example, the Geometry of building is Polygon, not Line.

Rule Four: Compliance of Coordinate Data Structure for a Feature

Detect whether the coordinate data structure of each Feature complies with the specification. For example, the coordinate value needs to be Coordinates (array type).

Rule Five: Consistency of the Start and End Coordinate Values for Polygon

If building, road, grass, water, and calder are polygons, you need to detect whether their start and end coordinate values are consistent first. Then you can determine whether the generated 3D model is closed.

Named Building

(main building)

name: string,

building: true,

height:number

Building key:

building/house/department

Value of type in geometry:

Polygon/MultiPolygon

If there are both building attribute and name attribute, the 3D model of the building will appear in the 3D City component. The facade color of the building will shine, representing the building lights.

Unnamed Building

(other building)

building: true,

height:number

Building key:

building/house/department

Value of type in geometry:

Polygon/MultiPolygon

If there is no building attribute, the 3D model of the building will not appear in the 3D City component.

If there is only the building attribute and no name attribute, the name of the building cannot be recognized in the 3D City component. The color of this building is dimmer than that of named buildings (if it is included in other buildings).

Named Road

(main road)

name: string,

road: true

Road key:

road/highway/lane/street

Value of type in geometry:

LineString/MultiLineString

If there are both road attribute and name attribute, the road will be displayed in the 3D City component with a flowing light effect to represent pedestrians and traffics.

Unnamed Road

(other road)

road: true

Road key:

road/highway/lane/street

Value of type in geometry:

LineString/MultiLineString

If there is no road attribute, the road will not be displayed in the 3D City component.

If there is only the road attribute and no name attribute, the name of the road cannot be recognized in the 3D City component. It is classified as other roads and its color is also dimmer.

Grassland

grass: true

Grass key:

grass/green/vegetation/park/leisure

Value of type in geometry:

Polygon/MultiPolygon

Water system

water: true

Water system key:

water/river/lake/natural

Value of type in geometry:

Polygon/MultiPolygon

bbox:calder

null

Value of type in geometry:

Polygon/MultiPolygon/LineString/MultiLineString

Special attributes:

Sometimes, you need to modify building scope manually to achieve certain effect.

You can create an empty scene through this method and use it with custom templates.

Add a Polygon, consider it as the first Feature, and add special attributes.

"calder:bbox": true

In this case, the scene scope (bbox) is based on the Polygon.

Example:

{
  "type": "FeatureCollection",
  "features": [
    {
      "type": "Feature",
      "properties": {
        "calder:bbox": true
      },
      "geometry": {
        "type": "Polygon",
        "coordinates": [
          [[109,34],[109.1,34],[109.1,34.1],[109,34.1],[109,34]]
        ]
      }
    }
  ]
}