A description of a polygon on the ellipsoid. The polygon is defined by a polygon hierarchy. Polygon geometry can be rendered with both
Primitive
and GroundPrimitive
.
Name | Type | Description | ||||||||||||||||||||||||||||||||||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
options |
Object |
Object with the following properties:
|
- PolygonGeometry#createGeometry
- PolygonGeometry#fromPositions
Example:
// 1. create a polygon from points
var polygon = new Cesium.PolygonGeometry({
polygonHierarchy : new Cesium.PolygonHierarchy(
Cesium.Cartesian3.fromDegreesArray([
-72.0, 40.0,
-70.0, 35.0,
-75.0, 30.0,
-70.0, 30.0,
-68.0, 40.0
])
)
});
var geometry = Cesium.PolygonGeometry.createGeometry(polygon);
// 2. create a nested polygon with holes
var polygonWithHole = new Cesium.PolygonGeometry({
polygonHierarchy : new Cesium.PolygonHierarchy(
Cesium.Cartesian3.fromDegreesArray([
-109.0, 30.0,
-95.0, 30.0,
-95.0, 40.0,
-109.0, 40.0
]),
[new Cesium.PolygonHierarchy(
Cesium.Cartesian3.fromDegreesArray([
-107.0, 31.0,
-107.0, 39.0,
-97.0, 39.0,
-97.0, 31.0
]),
[new Cesium.PolygonHierarchy(
Cesium.Cartesian3.fromDegreesArray([
-105.0, 33.0,
-99.0, 33.0,
-99.0, 37.0,
-105.0, 37.0
]),
[new Cesium.PolygonHierarchy(
Cesium.Cartesian3.fromDegreesArray([
-103.0, 34.0,
-101.0, 34.0,
-101.0, 36.0,
-103.0, 36.0
])
)]
)]
)]
)
});
var geometry = Cesium.PolygonGeometry.createGeometry(polygonWithHole);
// 3. create extruded polygon
var extrudedPolygon = new Cesium.PolygonGeometry({
polygonHierarchy : new Cesium.PolygonHierarchy(
Cesium.Cartesian3.fromDegreesArray([
-72.0, 40.0,
-70.0, 35.0,
-75.0, 30.0,
-70.0, 30.0,
-68.0, 40.0
])
),
extrudedHeight: 300000
});
var geometry = Cesium.PolygonGeometry.createGeometry(extrudedPolygon);
Demo:
See:
Members
-
The number of elements used to pack the object into an array.
Methods
-
staticCesium.PolygonGeometry.createGeometry(polygonGeometry) → Geometry|undefined
-
Computes the geometric representation of a polygon, including its vertices, indices, and a bounding sphere.
Name Type Description polygonGeometry
PolygonGeometry A description of the polygon. Returns:
The computed vertices and indices. -
staticCesium.PolygonGeometry.fromPositions(options) → PolygonGeometry
-
A description of a polygon from an array of positions. Polygon geometry can be rendered with both
Primitive
andGroundPrimitive
.Name Type Description options
Object Object with the following properties: Name Type Default Description positions
Array.<Cartesian3> An array of positions that defined the corner points of the polygon. height
Number 0.0
optional The height of the polygon. extrudedHeight
Number optional The height of the polygon extrusion. vertexFormat
VertexFormat VertexFormat.DEFAULT
optional The vertex attributes to be computed. stRotation
Number 0.0
optional The rotation of the texture coordinates, in radians. A positive rotation is counter-clockwise. ellipsoid
Ellipsoid Ellipsoid.WGS84
optional The ellipsoid to be used as a reference. granularity
Number CesiumMath.RADIANS_PER_DEGREE
optional The distance, in radians, between each latitude and longitude. Determines the number of positions in the buffer. perPositionHeight
Boolean false
optional Use the height of options.positions for each position instead of using options.height to determine the height. closeTop
Boolean true
optional When false, leaves off the top of an extruded polygon open. closeBottom
Boolean true
optional When false, leaves off the bottom of an extruded polygon open. Returns:
- PolygonGeometry#createGeometry
Example:
// create a polygon from points var polygon = Cesium.PolygonGeometry.fromPositions({ positions : Cesium.Cartesian3.fromDegreesArray([ -72.0, 40.0, -70.0, 35.0, -75.0, 30.0, -70.0, 30.0, -68.0, 40.0 ]) }); var geometry = Cesium.PolygonGeometry.createGeometry(polygon);
See:
-
Stores the provided instance into the provided array.
Name Type Default Description value
PolygonGeometry The value to pack. array
Array.<Number> The array to pack into. startingIndex
Number 0
optional The index into the array at which to start packing the elements. Returns:
The array that was packed into -
Retrieves an instance from a packed array.
Name Type Default Description array
Array.<Number> The packed array. startingIndex
Number 0
optional The starting index of the element to be unpacked. result
PolygonGeometry optional The object into which to store the result.