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GeometryInstanceAttribute

new Cesium.GeometryInstanceAttribute(options)
engine/Source/Core/GeometryInstanceAttribute.js 42

Values and type information for per-instance geometry attributes.
Name Type Description
options object Object with the following properties:
Name Type Default Description
componentDatatype ComponentDatatype The datatype of each component in the attribute, e.g., individual elements in values.
componentsPerAttribute number A number between 1 and 4 that defines the number of components in an attributes.
normalize boolean false optional When true and componentDatatype is an integer format, indicate that the components should be mapped to the range [0, 1] (unsigned) or [-1, 1] (signed) when they are accessed as floating-point for rendering.
value Array.<number> The value for the attribute.
Throws:
  • DeveloperError : options.componentsPerAttribute must be between 1 and 4.
Example:
const instance = new Cesium.GeometryInstance({
  geometry : Cesium.BoxGeometry.fromDimensions({
    dimensions : new Cesium.Cartesian3(1000000.0, 1000000.0, 500000.0)
  }),
  modelMatrix : Cesium.Matrix4.multiplyByTranslation(Cesium.Transforms.eastNorthUpToFixedFrame(
    Cesium.Cartesian3.fromDegrees(0.0, 0.0)), new Cesium.Cartesian3(0.0, 0.0, 1000000.0), new Cesium.Matrix4()),
  id : 'box',
  attributes : {
    color : new Cesium.GeometryInstanceAttribute({
      componentDatatype : Cesium.ComponentDatatype.UNSIGNED_BYTE,
      componentsPerAttribute : 4,
      normalize : true,
      value : [255, 255, 0, 255]
    })
  }
});
See:

Members

componentDatatype : ComponentDatatype
engine/Source/Core/GeometryInstanceAttribute.js 73

The datatype of each component in the attribute, e.g., individual elements in GeometryInstanceAttribute#value.
Default Value: undefined

componentsPerAttribute : number
engine/Source/Core/GeometryInstanceAttribute.js 92

A number between 1 and 4 that defines the number of components in an attributes. For example, a position attribute with x, y, and z components would have 3 as shown in the code example.
Default Value: undefined
Example:
show : new Cesium.GeometryInstanceAttribute({
  componentDatatype : Cesium.ComponentDatatype.UNSIGNED_BYTE,
  componentsPerAttribute : 1,
  normalize : true,
  value : [1.0]
})

normalize : boolean
engine/Source/Core/GeometryInstanceAttribute.js 117

When true and componentDatatype is an integer format, indicate that the components should be mapped to the range [0, 1] (unsigned) or [-1, 1] (signed) when they are accessed as floating-point for rendering.

This is commonly used when storing colors using ComponentDatatype.UNSIGNED_BYTE.

Default Value: false
Example:
attribute.componentDatatype = Cesium.ComponentDatatype.UNSIGNED_BYTE;
attribute.componentsPerAttribute = 4;
attribute.normalize = true;
attribute.value = [
  Cesium.Color.floatToByte(color.red),
  Cesium.Color.floatToByte(color.green),
  Cesium.Color.floatToByte(color.blue),
  Cesium.Color.floatToByte(color.alpha)
];

value : Array.<number>
engine/Source/Core/GeometryInstanceAttribute.js 136

The values for the attributes stored in a typed array. In the code example, every three elements in values defines one attributes since componentsPerAttribute is 3.
Default Value: undefined
Example:
show : new Cesium.GeometryInstanceAttribute({
  componentDatatype : Cesium.ComponentDatatype.UNSIGNED_BYTE,
  componentsPerAttribute : 1,
  normalize : true,
  value : [1.0]
})
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