# GeometryInstanceAttribute

#### new Cesium.GeometryInstanceAttribute(options)
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:

    var 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:

- ColorGeometryInstanceAttribute
- ShowGeometryInstanceAttribute
- DistanceDisplayConditionGeometryInstanceAttribute

### Members

#### componentDatatype : ComponentDatatype
Core/GeometryInstanceAttribute.js 68

The datatype of each component in the attribute, e.g., individual elements in `GeometryInstanceAttribute#value`.

Default Value: `undefined`

#### componentsPerAttribute : Number
Core/GeometryInstanceAttribute.js 87

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
Core/GeometryInstanceAttribute.js 112

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>
Core/GeometryInstanceAttribute.js 131

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]
    })