WebGL OES_vertex_array_object Khronos Ratified Extension Specification




WebGL working group (public_webgl 'at' khronos.org)


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Last modified date: July 15, 2014
Revision: 11


WebGL extension #5


Written against the WebGL API 1.0 specification.

Promoted to core and no longer available as an extension in WebGL API 2.0 specification.


This extension exposes the OES_vertex_array_object functionality to WebGL.

There are no WebGL-specific behavioral changes.

Consult the above extension for documentation, issues and new functions and enumerants.


[Exposed=(Window,Worker), LegacyNoInterfaceObject]
interface WebGLVertexArrayObjectOES : WebGLObject {

[Exposed=(Window,Worker), LegacyNoInterfaceObject]
interface OES_vertex_array_object {
    const GLenum VERTEX_ARRAY_BINDING_OES = 0x85B5;

    WebGLVertexArrayObjectOES? createVertexArrayOES();
    undefined deleteVertexArrayOES(WebGLVertexArrayObjectOES? arrayObject);
    [WebGLHandlesContextLoss] GLboolean isVertexArrayOES(WebGLVertexArrayObjectOES? arrayObject);
    undefined bindVertexArrayOES(WebGLVertexArrayObjectOES? arrayObject);

New Functions

WebGLVertexArrayObjectOES? createVertexArrayOES()
undefined deleteVertexArrayOES(WebGLVertexArrayObjectOES? arrayObject)
GLboolean isVertexArrayOES(WebGLVertexArrayObjectOES? arrayObject)
Returns false if the vertex array object's invalidated flag is set.
undefined bindVertexArrayOES(WebGLVertexArrayObjectOES? arrayObject)


The OES_vertex_array_object spec does not make it clear what happens to buffers that are deleted when they are referenced by vertex array objects. It is inferred that all buffers are reference counted.

Before OES_vertex_array_object there was no way to use a deleted buffer in a single context as the spec states it would be unbound from all bind points. After OES_vertex_array_object it is now possible to use deleted buffers.

Furthermore, the OpenGL ES 2.0 spec specifies that using a deleted buffer has undefined results including possibly corrupt rendering and generating GL errors. Undefined behavior is unacceptable for WebGL.

Revision History

Revision 1, 2011/01/27

Revision 2, 2011/11/12

Revision 3, 2011/12/06

Revision 4, 2011/12/07

Revision 5, 2012/01/03

Revision 6, 2012/09/24

Revision 7, 2012/10/16

Revision 8, 2013/05/08

Revision 9, 2013/05/14

Revision 10, 2013/05/15

Revision 11, 2014/07/15