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GeometryAttribute

GeometryAttribute

new

Values and type information for geometry attributes. A Geometry generally contains one or more attributes. All attributes together form the geometry's vertices.

Parameters:
Name Type Argument Default Description
options.componentDatatype ComponentDatatype <optional>
 undefined The datatype of each component in the attribute, e.g., individual elements in values.
options.componentsPerAttribute Number <optional>
 undefined A number between 1 and 4 that defines the number of components in an attributes.
options.normalize Boolean <optional>
 false 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.
options.values Array <optional>
 undefined The values for the attributes stored in a typed array.
Throws:
Example
var geometry = new Geometry({
  attributes : {
    position : new GeometryAttribute({
      componentDatatype : ComponentDatatype.FLOAT,
      componentsPerAttribute : 3,
      values : [
        0.0, 0.0, 0.0,
        7500000.0, 0.0, 0.0,
        0.0, 7500000.0, 0.0
      ]
    })
  },
  primitiveType : PrimitiveType.LINE_LOOP
});
See:
Source:

Members

:ComponentDatatype

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

:Number

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.
Example
attribute.componentDatatype : 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
]);
Default Value:
  • undefined

:Boolean

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}.

Example
attribute.componentDatatype : ComponentDatatype.UNSIGNED_BYTE,
attribute.componentsPerAttribute : 4,
attribute.normalize = true;
attribute.values = new Uint8Array([
  Color.floatToByte(color.red)
  Color.floatToByte(color.green)
  Color.floatToByte(color.blue)
  Color.floatToByte(color.alpha)
]);
Default Value:
  • false

:Array

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.
Example
attribute.componentDatatype : 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
]);
Default Value:
  • undefined