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GeometryAttribute

new Cesium.GeometryAttribute(options)
engine/Source/Core/GeometryAttribute.js 40

Values and type information for geometry attributes. A Geometry generally contains one or more attributes. All attributes together form the geometry's vertices.
Name Type Description
options object optional Object with the following properties:
Name Type Default Description
componentDatatype ComponentDatatype optional The datatype of each component in the attribute, e.g., individual elements in values.
componentsPerAttribute number optional 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.
values Array.<number> | Int8Array | Uint8Array | Int16Array | Uint16Array | Int32Array | Uint32Array | Float32Array | Float64Array optional The values for the attributes stored in a typed array.
Throws:
  • DeveloperError : options.componentsPerAttribute must be between 1 and 4.
Example:
const geometry = new Cesium.Geometry({
  attributes : {
    position : new Cesium.GeometryAttribute({
      componentDatatype : Cesium.ComponentDatatype.FLOAT,
      componentsPerAttribute : 3,
      values : new Float32Array([
        0.0, 0.0, 0.0,
        7500000.0, 0.0, 0.0,
        0.0, 7500000.0, 0.0
      ])
    })
  },
  primitiveType : Cesium.PrimitiveType.LINE_LOOP
});
See:

Members

componentDatatype : ComponentDatatype
engine/Source/Core/GeometryAttribute.js 71

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

componentsPerAttribute : number
engine/Source/Core/GeometryAttribute.js 91

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:
attribute.componentDatatype = Cesium.ComponentDatatype.FLOAT;
attribute.componentsPerAttribute = 3;
attribute.values = new Float32Array([
  0.0, 0.0, 0.0,
  7500000.0, 0.0, 0.0,
  0.0, 7500000.0, 0.0
]);

normalize : boolean
engine/Source/Core/GeometryAttribute.js 116

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.values = new Uint8Array([
  Cesium.Color.floatToByte(color.red),
  Cesium.Color.floatToByte(color.green),
  Cesium.Color.floatToByte(color.blue),
  Cesium.Color.floatToByte(color.alpha)
]);

values : Array.<number>|Int8Array|Uint8Array|Int16Array|Uint16Array|Int32Array|Uint32Array|Float32Array|Float64Array
engine/Source/Core/GeometryAttribute.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:
attribute.componentDatatype = Cesium.ComponentDatatype.FLOAT;
attribute.componentsPerAttribute = 3;
attribute.values = new Float32Array([
  0.0, 0.0, 0.0,
  7500000.0, 0.0, 0.0,
  0.0, 7500000.0, 0.0
]);
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