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CZML Content

kring edited this page May 2, 2012 · 28 revisions

This page describes the possible content of a CZML document or stream. Please read CZML Structure for an explanation of how a CZML document is put together.

NOTE: This is a work in progress and reflects our plans NOT our current capabilities.

Position

Specifies the position of the object in the world. The position has no direct visual representation, but it is used to locate billboards, labels, and other primitives attached to the object.

Property Name: position

Interpolatable: yes

Sub-properties:

Name Scope JSON Description
referenceFrame Interval string The reference frame in which cartesian positions are specified. Possible values are FIXED and INERTIAL. This property is ignored when specifying position with any type other than cartesian. If this property is not specified, the default reference frame is FIXED.
epoch Packet string The epoch (time 0.0), specified as an ISO 8601 date and time string, for times specified in epoch seconds. This property is required if a sample time or other property is specified in epoch seconds. It is ignored if this property is not defined by samples for this interval.
nextTime Packet string or number The time of the next sample within this interval, specified as either an ISO 8601 date and time string or as seconds since epoch. This property is used to determine if there is a gap between samples specified in different packets.
previousTime Packet string or number The time of the previous sample within this interval, specified as either an ISO 8601 date and time string or as seconds since epoch. This property is used to determine if there is a gap between samples specified in different packets.
cartesian Interval array The position specified as a Cartesian [X, Y, Z] position in the meters relative to the referenceFrame. If the array has three elements, the position is constant. If it has four or more elements, they are time-tagged samples arranged as [Time, X, Y, Z, Time, X, Y, Z, Time, X, Y, Z, ...], where Time is an ISO 8601 date and time string or seconds since epoch.
cartographicRadians Interval array The position specified as a WGS 84 Cartographic [Longitude, Latitude, Height] where longitude and latitude are in radians and height is in meters. If the array has three elements, the position is constant. If it has four or more elements, they are time-tagged samples arranged as [Time, Longitude, Latitude, Height, Time, Longitude, Latitude, Height, ...], where Time is an ISO 8601 date and time string or seconds since epoch.
cartographicDegrees Interval array The position specified as a WGS 84 Cartographic [Longitude, Latitude, Height] where longitude and latitude are in degrees and height is in meters. If the array has three elements, the position is constant. If it has four or more elements, they are time-tagged samples arranged as [Time, Longitude, Latitude, Height, Time, Longitude, Latitude, Height, ...], where Time is an ISO 8601 date and time string or seconds since epoch.
interpolationAlgorithm Interval string The algorithm to use for interpolation. Possible values are LAGRANGE, HERMITE, or GEODESIC. The default is LAGRANGE. If the position is not sampled over this interval, this property is ignored.
interpolationDegree Interval number The degree of the polynomial to use for interpolation. The default value is 1 meaning linear interpolation. The value of this property is ignored for GEODESIC interpolation.

Examples:

{
  "id": "MyObject",
  "position": { "cartographicDegrees": [-75.0, 40.0, 0.0] }
}
{
  "id": "InternationalSpaceStation",
  "position": {
    "referenceFrame": "INERTIAL",
    "epoch": "2012-05-02T12:00:00Z",
    "cartesian": [
      0.0, -6668447.2211117, 1201886.45913705, 146789.427467256,
      60.0, -6711432.84684144, 919677.673492462, -214047.552431458,
      90.0, -6721319.92231553, 776899.784034099, -394198.837519575,
      150.0, -6717826.447064, 488820.628328182, -752924.980158179,
      180.0, -6704450.41462847, 343851.784836767, -931084.800346031,
      240.0, -6654518.44949696, 52891.726433174, -1283967.69137678,
    ],
    "nextTime", 300.0,
    "interpolationAlgorithm", "LAGRANGE",
    "interpolationDegree", 5
  }
}

Orientation

Billboard

Point

Label

Polyline

Path

Polygon

Cone

Pyramid

Imagery

Layers