Constants for WebGL index datatypes. These corresponds to the
type
parameter of drawElements.
Members
8-bit unsigned byte corresponding to
UNSIGNED_BYTE
and the type
of an element in Uint8Array
.
32-bit unsigned int corresponding to
UNSIGNED_INT
and the type
of an element in Uint32Array
.
16-bit unsigned short corresponding to
UNSIGNED_SHORT
and the type
of an element in Uint16Array
.
Methods
staticCesium.IndexDatatype.createTypedArray(numberOfVertices, indicesLengthOrArray) → Uint16Array|Uint32Array
Creates a typed array that will store indices, using either
or Uint32Array
depending on the number of vertices.
Name | Type | Description |
---|---|---|
numberOfVertices |
Number | Number of vertices that the indices will reference. |
indicesLengthOrArray |
Number | Array | Passed through to the typed array constructor. |
Returns:
A
Uint16Array
or Uint32Array
constructed with indicesLengthOrArray
.
Example:
this.indices = Cesium.IndexDatatype.createTypedArray(positions.length / 3, numberOfIndices);
staticCesium.IndexDatatype.createTypedArrayFromArrayBuffer(numberOfVertices, sourceArray, byteOffset, length) → Uint16Array|Uint32Array
Creates a typed array from a source array buffer. The resulting typed array will store indices, using either
or Uint32Array
depending on the number of vertices.
Name | Type | Description |
---|---|---|
numberOfVertices |
Number | Number of vertices that the indices will reference. |
sourceArray |
ArrayBuffer | Passed through to the typed array constructor. |
byteOffset |
Number | Passed through to the typed array constructor. |
length |
Number | Passed through to the typed array constructor. |
Returns:
A
Uint16Array
or Uint32Array
constructed with sourceArray
, byteOffset
, and length
.
staticCesium.IndexDatatype.fromSizeInBytes(sizeInBytes) → IndexDatatype
Gets the datatype with a given size in bytes.
Name | Type | Description |
---|---|---|
sizeInBytes |
Number | The size of a single index in bytes. |
Returns:
The index datatype with the given size.
Returns the size, in bytes, of the corresponding datatype.
Name | Type | Description |
---|---|---|
indexDatatype |
IndexDatatype | The index datatype to get the size of. |
Returns:
The size in bytes.
Example:
// Returns 2
var size = Cesium.IndexDatatype.getSizeInBytes(Cesium.IndexDatatype.UNSIGNED_SHORT);
Validates that the provided index datatype is a valid
IndexDatatype
.
Name | Type | Description |
---|---|---|
indexDatatype |
IndexDatatype | The index datatype to validate. |
Returns:
true
if the provided index datatype is a valid value; otherwise, false
.
Example:
if (!Cesium.IndexDatatype.validate(indexDatatype)) {
throw new Cesium.DeveloperError('indexDatatype must be a valid value.');
}