WebGL, like its sister APIs (OpenGL and OpenGL ES), supports extensions. A complete list of extensions is available in the khronos webgl extension registry.
Canonical extension names, vendor prefixes and preferences
Extensions may be supported by browser vendors before being officially ratified (but only when they are in draft stage). In that case, their name can be prefixed by the vendor prefix (
WEBKIT_, etc.) or the extension is only available once a browser preference has been toggled.
If you wish to work with the bleeding edge of extensions, and want to keep working on upon ratification (assuming, of course, that the extension doesn't change in incompatible ways), that you query the canonical extension name as well as the vendor extension name. For instance:
var ext = ( gl.getExtension('OES_vertex_array_object') || gl.getExtension('MOZ_OES_vertex_array_object') || gl.getExtension('WEBKIT_OES_vertex_array_object') );
Note that, vendor prefix have been discouraged more and more and thus most browser implement experimental extensions behind a feature flag rather than vendor prefix.
The feature flags are:
chrome://flags/#enable-webgl-draft-extensionsin Chromium based browsers (Chrome, Opera).
WebGL extensions are prefixed with "ANGLE", "OES", "EXT" or "WEBGL". These prefixes reflect origin and intent:
- ANGLE_: Extensions that are written by the ANGLE library authors.
- OES_: Extensions that mirror functionality from OpenGL ES or OpenGL API extensions approved by the respective architecture review boards.
- EXT_: Extensions that mirror other OpenGL ES or OpenGL API extensions.
- WEBGL_: Extensions that are WebGL-specific and intended to be compatible with multiple web browsers. It should also be used for extensions which originated with the OpenGL ES or OpenGL APIs, but whose behavior has been significantly altered.
Querying available extensions
The WebGL context supports querying what extensions are available.
var available_extensions = gl.getSupportedExtensions();
WebGLRenderingContext.getSupportedExtensions() method returns an array of strings, one for each supported extension.
The current extensions are:
Enabling an extension
Before an extension can be used it has to be enabled using
WebGLRenderingContext.getExtension(). For example:
var float_texture_ext = gl.getExtension('OES_texture_float');
The return value is
null if the extension is not supported, or an extension object otherwise.
If an extension defines specific symbols or functions that are not available in the core specification of WebGL, they will be available on the extension object returned by the call to