Web/API/OES standard derivatives

The OES_standard_derivatives extension is part of the WebGL API and adds the GLSL derivative functions dFdx, dFdy, and fwidth.

WebGL extensions are available using the WebGLRenderingContext.getExtension() method. For more information, see also Using Extensions in the WebGL tutorial.

Availability: This extension is only available to WebGL1 contexts. In WebGL2, the functionality of this extension is available on the WebGL2 context by default. In WebGL 2, the constant is available as gl.FRAGMENT_SHADER_DERIVATIVE_HINT and it requires GLSL #version 300 es.

Constants

This extension exposes one new constant, which can be used in the hint() and getParameter() methods.

ext.FRAGMENT_SHADER_DERIVATIVE_HINT_OES: A Glenum indicating the accuracy of the derivative calculation for the GLSL built-in functions: dFdx, dFdy, and fwidth.

GLSL built-in functions

The following new functions can be used in GLSL shader code, if this extension is enabled:

genType dFdx(genType)
genType dFdy(genType)
genType fwidth(genType)

Examples

Enabling the extensions:

gl.getExtension('OES_standard_derivatives');
gl.getExtension('EXT_shader_texture_lod');

Shader code that avoids artifacts when wrapping texture coordinates:

<script type="x-shader/x-fragment">
#extension GL_EXT_shader_texture_lod : enable
#extension GL_OES_standard_derivatives : enable

uniform sampler2D myTexture;
varying vec2 texcoord;

void main(){
  gl_FragColor = texture2DGradEXT(myTexture, mod(texcoord, vec2(0.1, 0.5)), 
                                  dFdx(texcoord), dFdy(texcoord));
}
</script>

Specifications

Specification	Status	Comment
OES_standard_derivativesThe definition of 'OES_standard_derivatives' in that specification.	Recommendation	Initial definition.

Browser compatibility

The compatibility table in this page is generated from structured data. If you'd like to contribute to the data, please check out https://github.com/mdn/browser-compat-data and send us a pull request.

Update compatibility data on GitHub

	Desktop						Mobile
	Chrome	Edge	Firefox	Internet Explorer	Opera	Safari	Android webview	Chrome for Android	Firefox for Android	Opera for Android	Safari on iOS	Samsung Internet
`OES_standard_derivatives`	Chrome Full support Yes	Edge Full support ≤18	Firefox Full support 10	IE ?	Opera Full support Yes	Safari ?	WebView Android Full support Yes	Chrome Android Full support Yes	Firefox Android ?	Opera Android Full support Yes	Safari iOS ?	Samsung Internet Android Full support Yes

Legend

Full support: Full support
Compatibility unknown: Compatibility unknown