Canvas——绘制圆角矩形之详解

Posted 2023-02-11 zealifree005

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　　Canvas并没有提供绘制圆角矩形的方法,但是通过观察,我们可以发现,其实我们可以将圆角矩形分为四段,可以通过使用arcTo来实现。

　　我们假设起点为x,y.绘制的矩形宽高为w,h.圆角的半径为r;所以将起点设置在(x+r,y)处，然后acrTo(x+w,y,x+w,y+h,r),对于终点,其实只要y值大于绿色点的都是可以的(这部分在绘制曲线部分已经详述)。此处我们将终点设为(x+w,y+h);这就是第一段曲线。第一段曲线绘制完毕之后，画笔落在了下图绿色点的位置。

　　现在再看下第二段曲线:

　　因此我们直接使用arcTo(x+w,y+h,x,y+h,r)绘制出第二个圆角,第二个曲线绘制完毕后,画笔落在了绿色点位置。

　　我们可以使用同样的方法来绘制第三个圆角。

　　acrTo(x,y+h,x,y,r)

　　第四个圆角arcTo(x,y,x+w,y):

　　这样,一个圆角矩形就完成了。为了方便使用,我们可以将绘制圆角矩形的方法封装在一个函数,或者加入到CanvasRenderingContext2D的原型中。

　　x,y是矩形的起点;w,h是矩形的宽高;r是圆角矩形的半径.

<code class="hljs javascript has-numbering" style="display: block; padding: 0px; color: inherit; box-sizing: border-box; font-family: 'Source Code Pro', monospace;font-size:undefined; white-space: pre; border-radius: 0px; word-wrap: normal; background: transparent;">CanvasRenderingContext2D.prototype.roundRect = <span class="hljs-function" style="box-sizing: border-box;"><span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">function</span> <span class="hljs-params" style="color: rgb(102, 0, 102); box-sizing: border-box;">(x, y, w, h, r)</span> </span>
    <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (w < <span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">2</span> * r) r = w / <span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">2</span>;
    <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (h < <span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">2</span> * r) r = h / <span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">2</span>;
    <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">this</span>.beginPath();
    <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">this</span>.moveTo(x+r, y);
    <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">this</span>.arcTo(x+w, y, x+w, y+h, r);
    <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">this</span>.arcTo(x+w, y+h, x, y+h, r);
    <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">this</span>.arcTo(x, y+h, x, y, r);
    <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">this</span>.arcTo(x, y, x+w, y, r);
    <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">this</span>.closePath();
    <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">return</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">this</span>;
</code><ul class="pre-numbering" style="box-sizing: border-box; position: absolute; width: 50px; top: 0px; left: 0px; margin: 0px; padding: 6px 0px 40px; border-right-width: 1px; border-right-style: solid; border-right-color: rgb(221, 221, 221); list-style: none; text-align: right; background-color: rgb(238, 238, 238);"><li style="box-sizing: border-box; padding: 0px 5px;">1</li><li style="box-sizing: border-box; padding: 0px 5px;">2</li><li style="box-sizing: border-box; padding: 0px 5px;">3</li><li style="box-sizing: border-box; padding: 0px 5px;">4</li><li style="box-sizing: border-box; padding: 0px 5px;">5</li><li style="box-sizing: border-box; padding: 0px 5px;">6</li><li style="box-sizing: border-box; padding: 0px 5px;">7</li><li style="box-sizing: border-box; padding: 0px 5px;">8</li><li style="box-sizing: border-box; padding: 0px 5px;">9</li><li style="box-sizing: border-box; padding: 0px 5px;">10</li><li style="box-sizing: border-box; padding: 0px 5px;">11</li><li style="box-sizing: border-box; padding: 0px 5px;">12</li></ul><ul class="pre-numbering" style="box-sizing: border-box; position: absolute; width: 50px; top: 0px; left: 0px; margin: 0px; padding: 6px 0px 40px; border-right-width: 1px; border-right-style: solid; border-right-color: rgb(221, 221, 221); list-style: none; text-align: right; background-color: rgb(238, 238, 238);"><li style="box-sizing: border-box; padding: 0px 5px;">1</li><li style="box-sizing: border-box; padding: 0px 5px;">2</li><li style="box-sizing: border-box; padding: 0px 5px;">3</li><li style="box-sizing: border-box; padding: 0px 5px;">4</li><li style="box-sizing: border-box; padding: 0px 5px;">5</li><li style="box-sizing: border-box; padding: 0px 5px;">6</li><li style="box-sizing: border-box; padding: 0px 5px;">7</li><li style="box-sizing: border-box; padding: 0px 5px;">8</li><li style="box-sizing: border-box; padding: 0px 5px;">9</li><li style="box-sizing: border-box; padding: 0px 5px;">10</li><li style="box-sizing: border-box; padding: 0px 5px;">11</li><li style="box-sizing: border-box; padding: 0px 5px;">12</li></ul>

这里使用了return this,这样我们就可以像使用jQuery一样,使用链式语法。

完整代码如下:

<code class="hljs avrasm has-numbering" style="display: block; padding: 0px; color: inherit; box-sizing: border-box; font-family: 'Source Code Pro', monospace;font-size:undefined; white-space: pre; border-radius: 0px; word-wrap: normal; background: transparent;"><body>
    <canvas id = <span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">"palette"</span> width=<span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">"400px"</span> height=<span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">"400px"</span>>
        您的浏览器不支持Canvas标签，请升级或更换浏览器
    </canvas>
</body>
</html>
<script>
    var palette = document<span class="hljs-preprocessor" style="color: rgb(68, 68, 68); box-sizing: border-box;">.querySelector</span>(<span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">"#palette"</span>)<span class="hljs-preprocessor" style="color: rgb(68, 68, 68); box-sizing: border-box;">.getContext</span>(<span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">"2d"</span>)<span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">;</span>
    palette<span class="hljs-preprocessor" style="color: rgb(68, 68, 68); box-sizing: border-box;">.moveTo</span>(<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">0</span>,<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">0</span>)<span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">;</span>
    palette<span class="hljs-preprocessor" style="color: rgb(68, 68, 68); box-sizing: border-box;">.lineTo</span>(<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">0</span>,<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">300</span>)<span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">;</span>
    palette<span class="hljs-preprocessor" style="color: rgb(68, 68, 68); box-sizing: border-box;">.moveTo</span>(<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">50.5</span>,<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">0</span>)<span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">;</span>
    palette<span class="hljs-preprocessor" style="color: rgb(68, 68, 68); box-sizing: border-box;">.lineTo</span>(<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">50.5</span>,<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">300</span>)<span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">;</span>
    palette<span class="hljs-preprocessor" style="color: rgb(68, 68, 68); box-sizing: border-box;">.moveTo</span>(<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">100.5</span>,<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">0</span>)<span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">;</span>
    palette<span class="hljs-preprocessor" style="color: rgb(68, 68, 68); box-sizing: border-box;">.lineTo</span>(<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">100.5</span>,<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">300</span>)<span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">;</span>
    palette<span class="hljs-preprocessor" style="color: rgb(68, 68, 68); box-sizing: border-box;">.moveTo</span>(<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">150.5</span>,<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">0</span>)<span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">;</span>
    palette<span class="hljs-preprocessor" style="color: rgb(68, 68, 68); box-sizing: border-box;">.lineTo</span>(<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">150.5</span>,<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">300</span>)<span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">;</span>
    palette<span class="hljs-preprocessor" style="color: rgb(68, 68, 68); box-sizing: border-box;">.moveTo</span>(<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">200.5</span>,<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">0</span>)<span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">;</span>
    palette<span class="hljs-preprocessor" style="color: rgb(68, 68, 68); box-sizing: border-box;">.lineTo</span>(<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">200.5</span>,<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">300</span>)<span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">;</span>
    palette<span class="hljs-preprocessor" style="color: rgb(68, 68, 68); box-sizing: border-box;">.moveTo</span>(<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">250.5</span>,<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">0</span>)<span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">;</span>
    palette<span class="hljs-preprocessor" style="color: rgb(68, 68, 68); box-sizing: border-box;">.lineTo</span>(<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">250.5</span>,<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">300</span>)<span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">;</span>
    palette<span class="hljs-preprocessor" style="color: rgb(68, 68, 68); box-sizing: border-box;">.moveTo</span>(<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">300.5</span>,<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">0</span>)<span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">;</span>
    palette<span class="hljs-preprocessor" style="color: rgb(68, 68, 68); box-sizing: border-box;">.lineTo</span>(<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">300.5</span>,<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">300</span>)<span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">;</span>
    palette<span class="hljs-preprocessor" style="color: rgb(68, 68, 68); box-sizing: border-box;">.moveTo</span>(<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">0</span>,<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">0</span>)<span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">;</span>
    palette<span class="hljs-preprocessor" style="color: rgb(68, 68, 68); box-sizing: border-box;">.lineTo</span>(<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">300</span>,<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">0</span>)<span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">;</span>
    palette<span class="hljs-preprocessor" style="color: rgb(68, 68, 68); box-sizing: border-box;">.moveTo</span>(<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">0</span>,<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">50.5</span>)<span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">;</span>
    palette<span class="hljs-preprocessor" style="color: rgb(68, 68, 68); box-sizing: border-box;">.lineTo</span>(<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">300</span>,<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">50.5</span>)<span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">;</span>
    palette<span class="hljs-preprocessor" style="color: rgb(68, 68, 68); box-sizing: border-box;">.moveTo</span>(<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">0</span>,<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">100.5</span>)<span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">;</span>
    palette<span class="hljs-preprocessor" style="color: rgb(68, 68, 68); box-sizing: border-box;">.lineTo</span>(<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">300</span>,<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">100.5</span>)<span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">;</span>
    palette<span class="hljs-preprocessor" style="color: rgb(68, 68, 68); box-sizing: border-box;">.moveTo</span>(<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">0</span>,<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">150.5</span>)<span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">;</span>
    palette<span class="hljs-preprocessor" style="color: rgb(68, 68, 68); box-sizing: border-box;">.lineTo</span>(<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">300</span>,<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">150.5</span>)<span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">;</span>
    palette<span class="hljs-preprocessor" style="color: rgb(68, 68, 68); box-sizing: border-box;">.moveTo</span>(<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">0</span>,<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">200.5</span>)<span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">;</span>
    palette<span class="hljs-preprocessor" style="color: rgb(68, 68, 68); box-sizing: border-box;">.lineTo</span>(<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">300</span>,<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">200.5</span>)<span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">;</span>
    palette<span class="hljs-preprocessor" style="color: rgb(68, 68, 68); box-sizing: border-box;">.moveTo</span>(<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">0</span>,<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">250.5</span>)<span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">;</span>
    palette<span class="hljs-preprocessor" style="color: rgb(68, 68, 68); box-sizing: border-box;">.lineTo</span>(<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">300</span>,<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">250.5</span>)<span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">;</span>
    palette<span class="hljs-preprocessor" style="color: rgb(68, 68, 68); box-sizing: border-box;">.moveTo</span>(<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">0</span>,<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">300.5</span>)<span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">;</span>
    palette<span class="hljs-preprocessor" style="color: rgb(68, 68, 68); box-sizing: border-box;">.lineTo</span>(<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">300</span>,<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">300.5</span>)<span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">;</span>
    palette<span class="hljs-preprocessor" style="color: rgb(68, 68, 68); box-sizing: border-box;">.stroke</span>()<span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">;</span>

    CanvasRenderingContext2D<span class="hljs-preprocessor" style="color: rgb(68, 68, 68); box-sizing: border-box;">.prototype</span><span class="hljs-preprocessor" style="color: rgb(68, 68, 68); box-sizing: border-box;">.roundRect</span> = function (<span class="hljs-built_in" style="color: rgb(102, 0, 102); box-sizing: border-box;">x</span>, <span class="hljs-built_in" style="color: rgb(102, 0, 102); box-sizing: border-box;">y</span>, w, h, r) 
        if (w < <span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">2</span> * r) r = w / <span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">2</span><span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">;</span>
        if (h < <span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">2</span> * r) r = h / <span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">2</span><span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">;</span>
        this<span class="hljs-preprocessor" style="color: rgb(68, 68, 68); box-sizing: border-box;">.beginPath</span>()<span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">;</span>
        this<span class="hljs-preprocessor" style="color: rgb(68, 68, 68); box-sizing: border-box;">.moveTo</span>(<span class="hljs-built_in" style="color: rgb(102, 0, 102); box-sizing: border-box;">x</span>+r, <span class="hljs-built_in" style="color: rgb(102, 0, 102); box-sizing: border-box;">y</span>)<span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">;</span>
        this<span class="hljs-preprocessor" style="color: rgb(68, 68, 68); box-sizing: border-box;">.arcTo</span>(<span class="hljs-built_in" style="color: rgb(102, 0, 102); box-sizing: border-box;">x</span>+w, <span class="hljs-built_in" style="color: rgb(102, 0, 102); box-sizing: border-box;">y</span>, <span class="hljs-built_in" style="color: rgb(102, 0, 102); box-sizing: border-box;">x</span>+w, <span class="hljs-built_in" style="color: rgb(102, 0, 102); box-sizing: border-box;">y</span>+h, r)<span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">;</span>
        this<span class="hljs-preprocessor" style="color: rgb(68, 68, 68); box-sizing: border-box;">.arcTo</span>(<span class="hljs-built_in" style="color: rgb(102, 0, 102); box-sizing: border-box;">x</span>+w, <span class="hljs-built_in" style="color: rgb(102, 0, 102); box-sizing: border-box;">y</span>+h, <span class="hljs-built_in" style="color: rgb(102, 0, 102); box-sizing: border-box;">x</span>, <span class="hljs-built_in" style="color: rgb(102, 0, 102); box-sizing: border-box;">y</span>+h, r)<span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">;</span>
        this<span class="hljs-preprocessor" style="color: rgb(68, 68, 68); box-sizing: border-box;">.arcTo</span>(<span class="hljs-built_in" style="color: rgb(102, 0, 102); box-sizing: border-box;">x</span>, <span class="hljs-built_in" style="color: rgb(102, 0, 102); box-sizing: border-box;">y</span>+h, <span class="hljs-built_in" style="color: rgb(102, 0, 102); box-sizing: border-box;">x</span>, <span class="hljs-built_in" style="color: rgb(102, 0, 102); box-sizing: border-box;">y</span>, r)<span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">;</span>
        this<span class="hljs-preprocessor" style="color: rgb(68, 68, 68); box-sizing: border-box;">.arcTo</span>(<span class="hljs-built_in" style="color: rgb(102, 0, 102); box-sizing: border-box;">x</span>, <span class="hljs-built_in" style="color: rgb(102, 0, 102); box-sizing: border-box;">y</span>, <span class="hljs-built_in" style="color: rgb(102, 0, 102); box-sizing: border-box;">x</span>+w, <span class="hljs-built_in" style="color: rgb(102, 0, 102); box-sizing: border-box;">y</span>, r)<span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">;</span>
        this<span class="hljs-preprocessor" style="color: rgb(68, 68, 68); box-sizing: border-box;">.closePath</span>()<span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">;</span>
        return this<span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">;</span>
    
    palette<span class="hljs-preprocessor" style="color: rgb(68, 68, 68); box-sizing: border-box;">.lineWidth</span> = <span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">5</span><span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">;</span>
    palette<span class="hljs-preprocessor" style="color: rgb(68, 68, 68); box-sizing: border-box;">.strokeStyle</span> = <span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">"#F00"</span><span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">;</span>
    palette<span class="hljs-preprocessor" style="color: rgb(68, 68, 68); box-sizing: border-box;">.roundRect</span>(<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">50</span>,<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">50</span>,<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">200</span>,<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">150</span>,<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">30</span>)<span class="hljs-preprocessor" style="color: rgb(68, 68, 68); box-sizing: border-box;">.stroke</span>()<span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">;</span>
</script></code>

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