GLBufferAttribute

An alternative version of a buffer attribute with more control over the VBO.

The renderer does not construct a VBO for this kind of attribute. Instead, it uses whatever VBO is passed in constructor and can later be altered via the buffer property.

The most common use case for this class is when some kind of GPGPU calculation interferes or even produces the VBOs in question.

Notice that this class can only be used with WebGLRenderer.

Constructor

new GLBufferAttribute( buffer : WebGLBuffer, type : number, itemSize : number, elementSize : number, count : number, normalized : boolean )

Constructs a new GL buffer attribute.

buffer

The native WebGL buffer.
type

The native data type (e.g. gl.FLOAT).
itemSize

The item size.
elementSize

The corresponding size (in bytes) for the given type parameter.
count

The expected number of vertices in VBO.
normalized

Whether the data are normalized or not.

Default is false.

Properties

.buffer : WebGLBuffer

The native WebGL buffer.

.count : number

The expected number of vertices in VBO.

.elementSize : number

The corresponding size (in bytes) for the given type parameter.

.isGLBufferAttribute : boolean (readonly)

This flag can be used for type testing.

Default is true.

.itemSize : number

The item size, see BufferAttribute#itemSize.

.name : string

The name of the buffer attribute.

.needsUpdate : number

Flag to indicate that this attribute has changed and should be re-sent to the GPU. Set this to true when you modify the value of the array.

Default is false.

.normalized : boolean

Applies to integer data only. Indicates how the underlying data in the buffer maps to the values in the GLSL code. For instance, if buffer contains data of gl.UNSIGNED_SHORT, and normalized is true, the values 0 - +65535 in the buffer data will be mapped to 0.0f - +1.0f in the GLSL attribute. If normalized is false, the values will be converted to floats unmodified, i.e. 65535 becomes 65535.0f.

.type : number

The native data type.

.version : number

A version number, incremented every time the needsUpdate is set to true.

Methods

.setBuffer( buffer : WebGLBuffer ) : BufferAttribute

Sets the given native WebGL buffer.

buffer

The buffer to set.
Returns: A reference to this instance.

.setCount( count : number ) : BufferAttribute

Sets the count (the expected number of vertices in VBO).

count

The count.
Returns: A reference to this instance.

.setItemSize( itemSize : number ) : BufferAttribute

Sets the item size.

itemSize

The item size.
Returns: A reference to this instance.

.setType( type : number, elementSize : number ) : BufferAttribute

Sets the given native data type and element size.

type

The native data type (e.g. gl.FLOAT).
elementSize

The corresponding size (in bytes) for the given type parameter.
Returns: A reference to this instance.

Source

src/core/GLBufferAttribute.js