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diff --git a/files/zh-cn/web/api/canvasrenderingcontext2d/currenttransform/index.html b/files/zh-cn/web/api/canvasrenderingcontext2d/currenttransform/index.html new file mode 100644 index 0000000000..75302a7302 --- /dev/null +++ b/files/zh-cn/web/api/canvasrenderingcontext2d/currenttransform/index.html @@ -0,0 +1,178 @@ +--- +title: CanvasRenderingContext2D.currentTransform +slug: Web/API/CanvasRenderingContext2D/currentTransform +translation_of: Web/API/CanvasRenderingContext2D/currentTransform +--- +<div>{{APIRef()}} {{SeeCompatTable}}</div> + +<p><code style="font-style: normal;"><strong>CanvasRenderingContext2D</strong></code><strong><code>.currentTransform</code></strong> 属性，表示当前变换的矩阵。可以通过Canvas2D API 返回或者赋值为{{domxref("SVGMatrix")}}对象。</p> + +<h2 id="语法">语法</h2> + +<pre class="syntaxbox"><var>ctx.currentTransform [= value];</var> +</pre> + +<dl> + <dt><code>参考</code></dt> + <dd>{{domxref("SVGMatrix")}} 对象表示当前变换的矩阵。</dd> +</dl> + +<h2 id="示例">示例</h2> + +<h3 id="使用currentTransform_的方式"><code><font face="Open Sans, sans-serif">使用</font>currentTransform</code> 的方式</h3> + +<p>这是一段简单的代码片段，使用<span style="font-family: consolas,monaco,andale mono,monospace;">currentTransform属性设置变换矩阵。</span></p> + +<h4 id="HTML">HTML</h4> + +<pre class="brush: html"><canvas id="canvas"></canvas> +</pre> + +<h4 id="JavaScript">JavaScript</h4> + +<pre class="brush: js">var canvas = document.getElementById("canvas"); +var ctx = canvas.getContext("2d"); + +var matrix = ctx.currentTransform; +matrix.a = 1; +matrix.b = 1; +matrix.c = 0; +matrix.d = 1; +matrix.e = 0; +matrix.f = 0; +ctx.currentTransform = matrix; +ctx.fillRect(0,0,100,100); +</pre> + +<p>修改下面的代码并在线查看canvas的变化（确定使用支持这段代码特征的浏览器，可以查看兼容性列表）:</p> + +<div class="hidden"> +<h6 id="Playable_code">Playable code</h6> + +<pre class="brush: html"><canvas id="canvas" width="400" height="200" class="playable-canvas"></canvas> +<div class="playable-buttons"> + <input id="edit" type="button" value="Edit" /> + <input id="reset" type="button" value="Reset" /> +</div> +<textarea id="code" class="playable-code" style="height:150px"> +var matrix = ctx.currentTransform; +matrix.a = 1; +matrix.b = 1; +matrix.c = 0; +matrix.d = 1; +matrix.e = 0; +matrix.f = 0; +ctx.currentTransform = matrix; +ctx.fillRect(0,0,100,100);</textarea> +</pre> + +<pre class="brush: js">var canvas = document.getElementById("canvas"); +var ctx = canvas.getContext("2d"); +var textarea = document.getElementById("code"); +var reset = document.getElementById("reset"); +var edit = document.getElementById("edit"); +var code = textarea.value; + +function drawCanvas() { + ctx.clearRect(0, 0, canvas.width, canvas.height); + eval(textarea.value); +} + +reset.addEventListener("click", function() { + textarea.value = code; + drawCanvas(); +}); + +edit.addEventListener("click", function() { + textarea.focus(); +}) + +textarea.addEventListener("input", drawCanvas); +window.addEventListener("load", drawCanvas); +</pre> +</div> + +<p>{{ EmbedLiveSample('Playable_code', 700, 420) }}</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-currenttransform", "CanvasRenderingContext2D.currentTransform")}}</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>{{CompatibilityTable}}</p> + +<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>{{CompatVersionUnknown}} [1]</td> + <td>{{CompatNo}}<br> + {{bug(928150)}}</td> + <td>{{CompatNo}}</td> + <td>{{CompatNo}}</td> + <td>{{CompatNo}}</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>{{CompatNo}}</td> + <td>{{CompatNo}}</td> + <td>{{CompatNo}}</td> + <td>{{CompatNo}}</td> + <td>{{CompatNo}}</td> + <td>{{CompatNo}}</td> + </tr> + </tbody> +</table> +</div> + +<h3 id="Chrome-specific注解">Chrome-specific注解</h3> + +<ul> + <li>此特征默认无效。需要启用<code>ExperimentalCanvasFeatures</code> 标志进行测试。</li> +</ul> + +<h2 id="参见">参见</h2> + +<ul> + <li>接口定义， {{domxref("CanvasPattern")}}</li> + <li>{{domxref("SVGMatrix")}}</li> +</ul> |