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diff --git a/files/zh-cn/web/api/webglrenderingcontext/isenabled/index.html b/files/zh-cn/web/api/webglrenderingcontext/isenabled/index.html new file mode 100644 index 0000000000..9c87ead999 --- /dev/null +++ b/files/zh-cn/web/api/webglrenderingcontext/isenabled/index.html @@ -0,0 +1,193 @@ +--- +title: WebGLRenderingContext.isEnabled() +slug: Web/API/WebGLRenderingContext/isEnabled +translation_of: Web/API/WebGLRenderingContext/isEnabled +--- +<div>{{APIRef("WebGL")}}</div> + +<p><strong><code>WebGLRenderingContext.isEnabled()</code></strong> 是 <a href="/en-US/docs/Web/API/WebGL_API">WebGL API</a> 方法之一,用来检测给定的 WebGL 功能项在当前上下文是否可用。</p> + +<p>默认的,除了 <code>gl.DITHER</code>,所有的功能项都是未启用的。</p> + +<h2 id="句法">句法</h2> + +<pre class="syntaxbox">void <var>gl</var>.isEnabled(<var>cap</var>); +</pre> + +<h3 id="参数">参数</h3> + +<dl> + <dt><code>cap</code></dt> + <dd>{{domxref("GLenum")}} 指定待检测的 WebGL 功能项。可能的值有:</dd> + <dd> + <table class="standard-table"> + <thead> + <tr> + <th scope="col">Constant</th> + <th scope="col">Description</th> + </tr> + </thead> + <tbody> + <tr> + <td><code>gl.BLEND</code></td> + <td>Blending of the computed fragment color values. See {{domxref("WebGLRenderingContext.blendFunc()")}}.</td> + </tr> + <tr> + <td><code>gl.CULL_FACE</code></td> + <td>Culling of polygons. See {{domxref("WebGLRenderingContext.cullFace()")}}.</td> + </tr> + <tr> + <td><code>gl.DEPTH_TEST</code></td> + <td>Depth comparisons and updates to the depth buffer. See {{domxref("WebGLRenderingContext.depthFunc()")}}.</td> + </tr> + <tr> + <td><code>gl.DITHER</code></td> + <td>Dithering of color components before they get written to the color buffer.</td> + </tr> + <tr> + <td><code>gl.POLYGON_OFFSET_FILL</code></td> + <td>Adding an offset to depth values of polygon's fragments. See {{domxref("WebGLRenderingContext.polygonOffset()")}}.</td> + </tr> + <tr> + <td><code>gl.SAMPLE_ALPHA_TO_COVERAGE</code></td> + <td>Computation of a temporary coverage value determined by the alpha value.</td> + </tr> + <tr> + <td><code>gl.SAMPLE_COVERAGE</code></td> + <td>ANDing the fragment's coverage with the temporary coverage value. See {{domxref("WebGLRenderingContext.sampleCoverage()")}}.</td> + </tr> + <tr> + <td><code>gl.SCISSOR_TEST</code></td> + <td>Scissor test that discards fragments that are outside of the scissor rectangle. See {{domxref("WebGLRenderingContext.scissor()")}}.</td> + </tr> + <tr> + <td><code>gl.STENCIL_TEST</code></td> + <td>Stencil testing and updates to the stencil buffer. See {{domxref("WebGLRenderingContext.stencilFunc()")}}.</td> + </tr> + </tbody> + </table> + 当使用 {{domxref("WebGL2RenderingContext", "WebGL 2 context", "", 1)}} 的时候,下列附加的值也是可选用的。 + + <table class="standard-table"> + <thead> + <tr> + <th scope="col">Constant</th> + <th scope="col">Description</th> + </tr> + </thead> + <tbody> + <tr> + <td><code>gl.RASTERIZER_DISCARD</code></td> + <td>Primitives are discarded immediately before the rasterization stage, but after the optional transform feedback stage. <code>gl.clear()</code> commands are ignored.</td> + </tr> + </tbody> + </table> + </dd> +</dl> + +<h3 id="返回值">返回值</h3> + +<p>{{domxref("GLboolean")}} 指示能力项 <em>cap </em>可用 (<code>true</code>),不可用 (<code>false</code>)。</p> + +<h2 id="示例">示例</h2> + +<pre class="brush: js">gl.isEnabled(gl.STENCIL_TEST); +// false +</pre> + +<p>启用或停用给定的能力项,使用 {{domxref("WebGLRenderingContext.enable()")}} 方法和 {{domxref("WebGLRenderingContext.disable()")}} 方法:</p> + +<pre class="brush: js">gl.enable(gl.STENCIL_TEST); +gl.disable(gl.STENCIL_TEST); +</pre> + +<h2 id="规范">规范</h2> + +<table class="standard-table"> + <tbody> + <tr> + <th scope="col">Specification</th> + <th scope="col">Status</th> + <th scope="col">Comment</th> + </tr> + <tr> + <td>{{SpecName('WebGL', "#5.14.3", "isEnabled")}}</td> + <td>{{Spec2('WebGL')}}</td> + <td>Initial definition for WebGL.</td> + </tr> + <tr> + <td>{{SpecName('OpenGL ES 2.0', "glIsEnabled.xml", "glIsEnabled")}}</td> + <td>{{Spec2('OpenGL ES 2.0')}}</td> + <td>Man page of the (similar) OpenGL ES 2.0 API.</td> + </tr> + <tr> + <td>{{SpecName('WebGL2', "#3.7.2", "isEnabled")}}</td> + <td>{{Spec2('WebGL2')}}</td> + <td>Updated definition for WebGL 2.</td> + </tr> + <tr> + <td>{{SpecName('OpenGL ES 3.0', "glIsEnabled.xhtml", "glIsEnabled")}}</td> + <td>{{Spec2('OpenGL ES 3.0')}}</td> + <td>Man page of the (similar) OpenGL ES 3.0 API.</td> + </tr> + </tbody> +</table> + +<h2 id="浏览器兼容性">浏览器兼容性</h2> + +<div>{{CompatibilityTable}}</div> + +<div id="compat-desktop"> +<table class="compat-table"> + <tbody> + <tr> + <th>Feature</th> + <th>Chrome</th> + <th>Firefox (Gecko)</th> + <th>Internet Explorer</th> + <th>Opera</th> + <th>Safari</th> + </tr> + <tr> + <td>Basic support</td> + <td>{{CompatChrome("9")}}</td> + <td>{{CompatGeckoDesktop("2.0")}}</td> + <td>{{CompatIE("11")}}</td> + <td>{{CompatOpera("12")}}</td> + <td>{{CompatSafari("5.1")}}</td> + </tr> + </tbody> +</table> +</div> + +<div id="compat-mobile"> +<table class="compat-table"> + <tbody> + <tr> + <th>Feature</th> + <th>Android</th> + <th>Chrome for Android</th> + <th>Firefox Mobile (Gecko)</th> + <th>IE Mobile</th> + <th>Opera Mobile</th> + <th>Safari Mobile</th> + </tr> + <tr> + <td>Basic support</td> + <td>{{CompatUnknown}}</td> + <td>25</td> + <td>{{CompatVersionUnknown}}</td> + <td>{{CompatUnknown}}</td> + <td>12</td> + <td>8.1</td> + </tr> + </tbody> +</table> +</div> + +<h2 id="另见">另见</h2> + +<ul> + <li>{{domxref("WebGLRenderingContext.enable()")}}</li> + <li>{{domxref("WebGLRenderingContext.disable()")}}</li> +</ul> |