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GeometryInstance

new Cesium.GeometryInstance(options)
engine/Source/Core/GeometryInstance.js 51

Geometry instancing allows one Geometry object to be positions in several different locations and colored uniquely. For example, one BoxGeometry can be instanced several times, each with a different modelMatrix to change its position, rotation, and scale.
Name Type Description
options object Object with the following properties:
Name Type Default Description
geometry Geometry | GeometryFactory The geometry to instance.
modelMatrix Matrix4 Matrix4.IDENTITY optional The model matrix that transforms to transform the geometry from model to world coordinates.
id object optional A user-defined object to return when the instance is picked with Scene#pick or get/set per-instance attributes with Primitive#getGeometryInstanceAttributes.
attributes object optional Per-instance attributes like a show or color attribute shown in the example below.
Example:
// Create geometry for a box, and two instances that refer to it.
// One instance positions the box on the bottom and colored aqua.
// The other instance positions the box on the top and color white.
const geometry = Cesium.BoxGeometry.fromDimensions({
  vertexFormat : Cesium.VertexFormat.POSITION_AND_NORMAL,
  dimensions : new Cesium.Cartesian3(1000000.0, 1000000.0, 500000.0)
});
const instanceBottom = new Cesium.GeometryInstance({
  geometry : geometry,
  modelMatrix : Cesium.Matrix4.multiplyByTranslation(Cesium.Transforms.eastNorthUpToFixedFrame(
    Cesium.Cartesian3.fromDegrees(-75.59777, 40.03883)), new Cesium.Cartesian3(0.0, 0.0, 1000000.0), new Cesium.Matrix4()),
  attributes : {
    color : Cesium.ColorGeometryInstanceAttribute.fromColor(Cesium.Color.AQUA)
  },
  id : 'bottom'
});
const instanceTop = new Cesium.GeometryInstance({
  geometry : geometry,
  modelMatrix : Cesium.Matrix4.multiplyByTranslation(Cesium.Transforms.eastNorthUpToFixedFrame(
    Cesium.Cartesian3.fromDegrees(-75.59777, 40.03883)), new Cesium.Cartesian3(0.0, 0.0, 3000000.0), new Cesium.Matrix4()),
  attributes : {
    color : Cesium.ColorGeometryInstanceAttribute.fromColor(Cesium.Color.AQUA)
  },
  id : 'top'
});
See:

Members

attributes : object
engine/Source/Core/GeometryInstance.js 110

Per-instance attributes like ColorGeometryInstanceAttribute or ShowGeometryInstanceAttribute. Geometry attributes varying per vertex; these attributes are constant for the entire instance.
Default Value: undefined

geometry : Geometry
engine/Source/Core/GeometryInstance.js 67

The geometry being instanced.
Default Value: undefined

id : object
engine/Source/Core/GeometryInstance.js 93

User-defined object returned when the instance is picked or used to get/set per-instance attributes.
Default Value: undefined
See:

modelMatrix : Matrix4
engine/Source/Core/GeometryInstance.js 79

The 4x4 transformation matrix that transforms the geometry from model to world coordinates. When this is the identity matrix, the geometry is drawn in world coordinates, i.e., Earth's WGS84 coordinates. Local reference frames can be used by providing a different transformation matrix, like that returned by Transforms.eastNorthUpToFixedFrame.
Default Value: Matrix4.IDENTITY
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