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---
title: WebGLRenderingContext.enable()
slug: Web/API/WebGLRenderingContext/enable
translation_of: Web/API/WebGLRenderingContext/enable
---
<div>{{APIRef("WebGL")}}</div>
<p>Метод <strong><code>WebGLRenderingContext.enable()</code></strong> из <a href="/en-US/docs/Web/API/WebGL_API">WebGL API</a> активирует определённые возможности WebGL для текущего контекста.</p>
<h2 id="Синтаксис">Синтаксис</h2>
<pre class="syntaxbox">void <var>gl</var>.enable(<var>cap</var>);
</pre>
<h3 id="Параметры">Параметры</h3>
<dl>
<dt><code>cap</code></dt>
<dd>A {{domxref("GLenum")}} specifying which WebGL capability to enable. Possible values:</dd>
<dd>
<table class="standard-table">
<thead>
<tr>
<th scope="col">Константа</th>
<th scope="col">Описание</th>
</tr>
</thead>
<tbody>
<tr>
<td><code>gl.BLEND</code></td>
<td>Активирует с<span class="short_text" id="result_box" lang="ru"><span>мешение значений цветов вычисленного фрагмента</span></span>. Смотри {{domxref("WebGLRenderingContext.blendFunc()")}}.</td>
</tr>
<tr>
<td><code>gl.CULL_FACE</code></td>
<td>Активирует отбраковку полигонов. Смотри {{domxref("WebGLRenderingContext.cullFace()")}}.</td>
</tr>
<tr>
<td><code>gl.DEPTH_TEST</code></td>
<td>Активирует сравнения глубин и обновления для буфера глубины. Смотри {{domxref("WebGLRenderingContext.depthFunc()")}}.</td>
</tr>
<tr>
<td><code>gl.DITHER</code></td>
<td>Activates dithering of color components before they get written to the color buffer.</td>
</tr>
<tr>
<td><code>gl.POLYGON_OFFSET_FILL</code></td>
<td>Activates 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>Activates the computation of a temporary coverage value determined by the alpha value.</td>
</tr>
<tr>
<td><code>gl.SAMPLE_COVERAGE</code></td>
<td>Activates 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>Activates the 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>Activates stencil testing and updates to the stencil buffer. See {{domxref("WebGLRenderingContext.stencilFunc()")}}.</td>
</tr>
</tbody>
</table>
When using a {{domxref("WebGL2RenderingContext", "WebGL 2 context", "", 1)}}, the following values are available additionally:
<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="Return_value">Return value</h3>
<p>None.</p>
<h2 id="Examples">Examples</h2>
<pre class="brush: js">gl.enable(gl.DITHER);
</pre>
<p>To check if a capability is enabled, use the {{domxref("WebGLRenderingContext.isEnabled()")}} method:</p>
<pre class="brush: js">gl.isEnabled(gl.DITHER);
// true
</pre>
<h2 id="Specifications">Specifications</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", "enable")}}</td>
<td>{{Spec2('WebGL')}}</td>
<td>Initial definition for WebGL.</td>
</tr>
<tr>
<td>{{SpecName('OpenGL ES 2.0', "glEnable.xml", "glEnable")}}</td>
<td>{{Spec2('OpenGL ES 2.0')}}</td>
<td>Man page of the OpenGL ES 2.0 API.</td>
</tr>
<tr>
<td>{{SpecName('OpenGL ES 3.0', "glEnable.xhtml", "glEnable")}}</td>
<td>{{Spec2('OpenGL ES 3.0')}}</td>
<td>Man page of the OpenGL ES 3.0 API.</td>
</tr>
</tbody>
</table>
<h2 id="Browser_compatibility">Browser compatibility</h2>
<p>{{Compat}}</p>
<h2 id="See_also">See also</h2>
<ul>
<li>{{domxref("WebGLRenderingContext.disable()")}}</li>
<li>{{domxref("WebGLRenderingContext.isEnabled()")}}</li>
</ul>
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