--- title: CanvasRenderingContext2D.imageSmoothingEnabled slug: Web/API/CanvasRenderingContext2D/imageSmoothingEnabled tags: - Canvas - CanvasRenderingContext2D translation_of: Web/API/CanvasRenderingContext2D/imageSmoothingEnabled --- <div>{{APIRef}}</div> <p><code><strong>CanvasRenderingContext2D</strong></code><strong><code>.imageSmoothingEnabled</code></strong> 是 Canvas 2D API 用来设置图片是否平滑的属性,true表示图片平滑(默认值),false表示图片不平滑。当我们获取 <code>imageSmoothingEnabled</code> 属性值时, 它会返回最新设置的值。</p> <p> 以缩放画布为例,这个属性对像素为主的游戏很有用。默认的改变大小的算法会造成图片模糊并且破坏图片原有的像素。 如果那样的话,设置属性值为false。 参见 CSS {{cssxref("image-rendering")}} 属性。</p> <div class="blockIndicator note"> <p><strong>注意:</strong>您可以使用{{domxref("CanvasRenderingContext2D.imageSmoothingQuality", "imageSmoothingQuality")}}属性来调整平滑质量。</p> </div> <h2 id="语法">语法</h2> <pre class="syntaxbox"><var><em>ctx</em>.imageSmoothingEnabled = value;</var></pre> <h3 id="选项">选项</h3> <dl> <dt><code>value</code></dt> <dd>一个{{jsxref("Boolean")}} 类型的值,表示图片是否平滑。</dd> </dl> <h2 id="示例">示例</h2> <h3 id="Using_the_globalAlpha_property" name="Using_the_globalAlpha_property">使用 <code>imageSmoothingEnabled</code> 属性</h3> <p>本示例比较了三个图像。 第一个图像以其自然大小绘制,第二个图像缩放为3倍并启用了图像平滑,而第三个图像缩放为3倍但禁用了图像平滑。</p> <h4 id="HTML">HTML</h4> <pre class="brush: html"><canvas id="canvas" width="460" height="210"></canvas></pre> <h4 id="JavaScript">JavaScript</h4> <pre class="brush: js">const canvas = document.getElementById('canvas'); const ctx = canvas.getContext('2d'); ctx.font = '16px sans-serif'; ctx.textAlign = 'center'; const img = new Image(); img.src = 'https://interactive-examples.mdn.mozilla.net/media/examples/star.png'; img.onload = function() { const w = img.width, h = img.height; ctx.fillText('Source', w * .5, 20); ctx.drawImage(img, 0, 24, w, h); ctx.fillText('Smoothing = TRUE', w * 2.5, 20); <code> ctx.imageSmoothingEnabled = true;</code> ctx.drawImage(img, w, 24, w * 3, h * 3); ctx.fillText('Smoothing = FALSE', w * 5.5, 20); <code> ctx.imageSmoothingEnabled = false;</code> ctx.drawImage(img, w * 4, 24, w * 3, h * 3); }; </pre> <div class="hidden"> <h2 id="Disabling_image_smoothing">Disabling_image_smoothing</h2> <h3 id="HTML_2">HTML</h3> <pre class="brush: html"><canvas id="canvas" width="460" height="210"></canvas></pre> <h3 id="JavaScript_2">JavaScript</h3> <pre class="brush: js">const canvas = document.getElementById('canvas'); const ctx = canvas.getContext('2d'); ctx.font = '16px sans-serif'; ctx.textAlign = 'center'; const img = new Image(); img.src = 'https://interactive-examples.mdn.mozilla.net/media/examples/star.png'; img.onload = function() { const w = img.width, h = img.height; ctx.fillText('Source', w * .5, 20); ctx.drawImage(img, 0, 24, w, h); ctx.fillText('Smoothing = TRUE', w * 2.5, 20); <code> ctx.imageSmoothingEnabled = true;</code> ctx.drawImage(img, w, 24, w * 3, h * 3); ctx.fillText('Smoothing = FALSE', w * 5.5, 20); <code> ctx.imageSmoothingEnabled = false;</code> ctx.drawImage(img, w * 4, 24, w * 3, h * 3); }; </pre> </div> <h4 id="结果">结果</h4> <p>{{ EmbedLiveSample('Disabling_image_smoothing', 700, 240) }}</p> <h2 id="规范描述">规范描述</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('HTML WHATWG', "scripting.html#dom-context-2d-imagesmoothingenabled", "CanvasRenderingContext2D.imageSmoothingEnabled")}}</td> <td>{{Spec2('HTML WHATWG')}}</td> <td></td> </tr> </tbody> </table> <h2 id="浏览器兼容性">浏览器兼容性</h2> <p>{{Compat("api.CanvasRenderingContext2D.imageSmoothingEnabled")}}</p> <div id="compat-mobile"></div> <h2 id="参见">参见</h2> <ul> <li>接口定义, {{domxref("CanvasRenderingContext2D")}}</li> <li>{{cssxref("image-rendering")}}</li> </ul>