OES_standard_derivatives

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常量
GLSL built-in functions
范例
规范
浏览器兼容性
另请参阅
相关话题

OES_standard_derivatives 扩展属于 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 使用扩展在 WebGL 教程 .

可用性： 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: 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	注释
OES_standard_derivatives The definition of 'OES_standard_derivatives' in that specification.	推荐	初始定义。

浏览器兼容性

更新 GitHub 上的兼容性数据

	桌面						移动
	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

在此页

常量

GLSL built-in functions

范例

规范

浏览器兼容性

图例

另请参阅

元数据

相关话题