OES_standard_derivatives

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

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

常量

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

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

范例

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>
					

规范

规范 状态 Comment
OES_standard_derivatives
The definition of 'OES_standard_derivatives' in that specification.
Recommendation 初始定义。

浏览器兼容性

更新 GitHub 上的兼容性数据
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 Yes Edge ≤18 Firefox 10 IE ? Opera Yes Safari ? WebView Android Yes Chrome Android Yes Firefox Android ? Opera Android Yes Safari iOS ? Samsung Internet Android Yes

图例

完整支持
完整支持
兼容性未知
兼容性未知

另请参阅