A description of an ellipse on an ellipsoid. Ellipse geometry can be rendered with both
Primitive
and GroundPrimitive
.
参数名称 | 类型 | 描述信息 | ||||||||||||||||||||||||||||||||||||||||||||
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options |
object |
Object with the following properties:
|
Throws:
-
DeveloperError : semiMajorAxis and semiMinorAxis must be greater than zero.
-
DeveloperError : semiMajorAxis must be greater than or equal to the semiMinorAxis.
-
DeveloperError : granularity must be greater than zero.
使用示例:
// Create an ellipse.
const ellipse = new Cesium.EllipseGeometry({
center : Cesium.Cartesian3.fromDegrees(-75.59777, 40.03883),
semiMajorAxis : 500000.0,
semiMinorAxis : 300000.0,
rotation : Cesium.Math.toRadians(60.0)
});
const geometry = Cesium.EllipseGeometry.createGeometry(ellipse);
参考:
成员(属性)
The number of elements used to pack the object into an array.
方法
static Cesium.EllipseGeometry.computeRectangle(options, result) → Rectangle
Computes the bounding rectangle based on the provided options
参数名称 | 类型 | 描述信息 | ||||||||||||||||||||||||||||
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options |
object |
Object with the following properties:
|
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result |
Rectangle | 可选 An object in which to store the result |
返回值:
The result rectangle
static Cesium.EllipseGeometry.createGeometry(ellipseGeometry) → Geometry|undefined
Computes the geometric representation of a ellipse on an ellipsoid, including its vertices, indices, and a bounding sphere.
参数名称 | 类型 | 描述信息 |
---|---|---|
ellipseGeometry |
EllipseGeometry | A description of the ellipse. |
返回值:
The computed vertices and indices.
Stores the provided instance into the provided array.
参数名称 | 类型 | 默认值 | 描述信息 |
---|---|---|---|
value |
EllipseGeometry | The value to pack. | |
array |
Array.<number> | The array to pack into. | |
startingIndex |
number |
0
|
可选 The index into the array at which to start packing the elements. |
返回值:
The array that was packed into
static Cesium.EllipseGeometry.unpack(array, startingIndex, result) → EllipseGeometry
Retrieves an instance from a packed array.
参数名称 | 类型 | 默认值 | 描述信息 |
---|---|---|---|
array |
Array.<number> | The packed array. | |
startingIndex |
number |
0
|
可选 The starting index of the element to be unpacked. |
result |
EllipseGeometry | 可选 The object into which to store the result. |
返回值:
The modified result parameter or a new EllipseGeometry instance if one was not provided.