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diff --git a/files/pt-br/web/api/htmlcanvaselement/index.html b/files/pt-br/web/api/htmlcanvaselement/index.html new file mode 100644 index 0000000000..c2121aab9a --- /dev/null +++ b/files/pt-br/web/api/htmlcanvaselement/index.html @@ -0,0 +1,264 @@ +--- +title: HTMLCanvasElement +slug: Web/API/HTMLCanvasElement +tags: + - API + - Canvas + - HTML DOM + - Interface + - NeedsTranslation + - Reference + - TopicStub +translation_of: Web/API/HTMLCanvasElement +--- +<div> +<div>{{APIRef("Canvas API")}}</div> +</div> + +<p>The <strong><code>HTMLCanvasElement</code></strong> interface provides properties and methods for manipulating the layout and presentation of canvas elements. The <code>HTMLCanvasElement</code> interface also inherits the properties and methods of the {{domxref("HTMLElement")}} interface.</p> + +<p>{{InheritanceDiagram(600, 120)}}</p> + +<h2 id="Properties">Properties</h2> + +<p><em>Inherits properties from its parent, </em><em>{{domxref("HTMLElement")}}.</em></p> + +<dl> + <dt>{{domxref("HTMLCanvasElement.height")}}</dt> + <dd>Is a positive <code>integer</code> reflecting the {{htmlattrxref("height", "canvas")}} HTML attribute of the {{HTMLElement("canvas")}} element interpreted in CSS pixels. When the attribute is not specified, or if it is set to an invalid value, like a negative, the default value of <code>150</code> is used.</dd> + <dt>{{domxref("HTMLCanvasElement.mozOpaque")}} {{non-standard_inline}}</dt> + <dd>Is a {{jsxref("Boolean")}} reflecting the {{htmlattrxref("moz-opaque", "canvas")}} HTML attribute of the {{HTMLElement("canvas")}} element. It lets the canvas know whether or not translucency will be a factor. If the canvas knows there's no translucency, painting performance can be optimized.</dd> + <dt>{{domxref("HTMLCanvasElement.width")}}</dt> + <dd>Is a positive <code>integer</code> reflecting the {{htmlattrxref("width", "canvas")}} HTML attribute of the {{HTMLElement("canvas")}} element interpreted in CSS pixels. When the attribute is not specified, or if it is set to an invalid value, like a negative, the default value of <code>300</code> is used.</dd> + <dt>{{domxref("HTMLCanvasElement.mozPrintCallback")}}{{non-standard_inline}}</dt> + <dd>Is a <code>function</code> that is Initially null, Web content can set this to a JavaScript function that will be called if the page is printed. This function can then redraw the canvas at a higher resolution that is suitable for the printer being used. <a href="https://blog.mozilla.org/labs/2012/09/a-new-way-to-control-printing-output/">See this blog post.</a></dd> +</dl> + +<h2 id="Methods">Methods</h2> + +<p><em>Inherits methods from its parent, </em><em>{{domxref("HTMLElement")}}.</em></p> + +<dl> + <dt>{{domxref("HTMLCanvasElement.captureStream()")}} {{experimental_inline}}</dt> + <dd>Returns a {{domxref("CanvasCaptureMediaStream")}} that is a real-time video capture of the surface of the canvas.</dd> + <dt>{{domxref("HTMLCanvasElement.getContext()")}}</dt> + <dd>Returns a drawing context on the canvas, or null if the context ID is not supported. A drawing context lets you draw on the canvas. Calling getContext with <code>"2d"</code> returns a {{domxref("CanvasRenderingContext2D")}} object, whereas calling it with <code>"experimental-webgl"</code> (or <code>"webgl"</code>) returns a {{domxref("WebGLRenderingContext")}} object. This context is only available on browsers that implement <a href="/en-US/docs/Web/WebGL">WebGL</a>.</dd> + <dt>{{domxref("HTMLCanvasElement.toDataURL()")}}</dt> + <dd>Returns a data-URL containing a representation of the image in the format specified by the <code>type</code> parameter (defaults to <code>png</code>). The returned image is in a resolution of 96dpi.</dd> + <dt>{{domxref("HTMLCanvasElement.toBlob()")}}</dt> + <dd>Creates a {{domxref("Blob")}} object representing the image contained in the canvas; this file may be cached on the disk or stored in memory at the discretion of the user agent.</dd> + <dt>{{domxref("HTMLCanvasElement.transferControlToOffscreen()")}} {{experimental_inline}}</dt> + <dd>Transfers control to an {{domxref("OffscreenCanvas")}} object, either on the main thread or on a worker.</dd> + <dt>{{domxref("HTMLCanvasElement.mozGetAsFile()")}} {{non-standard_inline}} {{deprecated_inline}}</dt> + <dd>Returns a {{domxref("File")}} object representing the image contained in the canvas; this file is a memory-based file, with the specified <code>name</code>. If <code>type</code> is not specified, the image type is <code>image/png</code>.</dd> +</dl> + +<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('Media Capture DOM Elements', '#html-media-element-media-capture-extensions', 'HTMLCanvasElement')}}</td> + <td>{{Spec2('Media Capture DOM Elements')}}</td> + <td>Adds the method <code>captureStream()</code>.</td> + </tr> + <tr> + <td>{{SpecName('HTML WHATWG', "#the-canvas-element", "HTMLCanvasElement")}}</td> + <td>{{Spec2('HTML WHATWG')}}</td> + <td>The method <code>getContext()</code> now returns a {{domxref("RenderingContext")}} rather than an opaque <code>object</code>.<br> + The methods <code>probablySupportsContext()</code>, <code>setContext()</code> and <code>transferControlToProxy()</code>have been added.</td> + </tr> + <tr> + <td>{{SpecName('HTML5.1', "scripting-1.html#the-canvas-element", "HTMLCanvasElement")}}</td> + <td>{{Spec2('HTML5.1')}}</td> + <td> </td> + </tr> + <tr> + <td>{{SpecName('HTML5 W3C', "scripting-1.html#the-canvas-element", "HTMLCanvasElement")}}</td> + <td>{{Spec2('HTML5 W3C')}}</td> + <td>Initial definition.</td> + </tr> + </tbody> +</table> + +<h2 id="Browser_compatibility">Browser compatibility</h2> + +<div>{{CompatibilityTable}}</div> + +<div id="compat-desktop"> +<table class="compat-table"> + <tbody> + <tr> + <th>Feature</th> + <th>Chrome</th> + <th>Edge</th> + <th>Firefox (Gecko)</th> + <th>Internet Explorer</th> + <th>Opera</th> + <th>Safari</th> + </tr> + <tr> + <td>Basic support (<code>2D</code> context)</td> + <td>4.0</td> + <td>{{CompatVersionUnknown}}</td> + <td>{{CompatGeckoDesktop('1.9.2')}}</td> + <td>9.0</td> + <td>9.0 [1]</td> + <td>3.1</td> + </tr> + <tr> + <td><code>toBlob()</code></td> + <td>50</td> + <td>{{CompatNo}}</td> + <td>{{CompatGeckoDesktop('19')}} [2]</td> + <td>{{CompatUnknown}}</td> + <td>{{CompatUnknown}}</td> + <td>{{CompatNo}} (bug <a href="https://bugs.webkit.org/show_bug.cgi?id=71270">71270</a>)</td> + </tr> + <tr> + <td><code>probablySupportsContext()</code>,<br> + <code>setContext()</code>,<br> + <code>transferControlToProxy()</code> {{obsolete_inline}}</td> + <td>{{CompatNo}}</td> + <td>{{CompatUnknown}}</td> + <td>{{CompatNo}}</td> + <td>{{CompatNo}}</td> + <td>{{CompatNo}}</td> + <td>{{CompatNo}}</td> + </tr> + <tr> + <td><code>mozGetAsFile()</code> {{non-standard_inline}} {{deprecated_inline}}</td> + <td>{{CompatNo}}</td> + <td>{{CompatNo}}</td> + <td>{{CompatGeckoDesktop('2')}}</td> + <td>{{CompatNo}}</td> + <td>{{CompatNo}}</td> + <td>{{CompatNo}}</td> + </tr> + <tr> + <td><code>captureStream()</code> {{experimental_inline}}</td> + <td>{{CompatNo}}</td> + <td>{{CompatNo}}</td> + <td>{{CompatGeckoDesktop('41')}}</td> + <td>{{CompatNo}}</td> + <td>{{CompatNo}}</td> + <td>{{CompatNo}}</td> + </tr> + <tr> + <td><code>transferControlToOffscreen()</code> {{experimental_inline}}</td> + <td>{{CompatNo}}</td> + <td>{{CompatNo}}</td> + <td>{{CompatGeckoDesktop(44)}} [3]</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>Edge</th> + <th>Firefox Mobile (Gecko)</th> + <th>IE Mobile</th> + <th>Opera Mobile</th> + <th>Safari Mobile</th> + </tr> + <tr> + <td>Basic support (<code>2D</code> context)</td> + <td>2.1</td> + <td>{{CompatVersionUnknown}}</td> + <td>{{CompatVersionUnknown}}</td> + <td>{{CompatVersionUnknown}}</td> + <td>{{CompatUnknown}}</td> + <td>10.0 [1]</td> + <td>3.2</td> + </tr> + <tr> + <td><code>webgl</code> context</td> + <td>{{CompatUnknown}}</td> + <td>{{CompatUnknown}}</td> + <td>{{CompatUnknown}}</td> + <td>{{CompatVersionUnknown}} as <code>experimental-webgl</code></td> + <td>{{CompatUnknown}}</td> + <td>{{CompatUnknown}}</td> + <td>{{CompatUnknown}}</td> + </tr> + <tr> + <td><code>toBlob()</code></td> + <td>{{CompatNo}} (bug <a href="http://crbug.com/67587">67587</a>)</td> + <td>50</td> + <td>{{CompatNo}}</td> + <td>{{CompatGeckoMobile('18')}} [2]</td> + <td>{{CompatUnknown}}</td> + <td>{{CompatUnknown}}</td> + <td>{{CompatNo}} (bug <a href="https://bugs.webkit.org/show_bug.cgi?id=71270">71270</a>)</td> + </tr> + <tr> + <td><code>probablySupportsContext()</code>,<br> + <code>setContext()</code>,<br> + <code>transferControlToProxy() </code>{{obsolete_inline}}</td> + <td>{{CompatNo}}</td> + <td>{{CompatNo}}</td> + <td>{{CompatNo}}</td> + <td>{{CompatNo}}</td> + <td>{{CompatNo}}</td> + <td>{{CompatNo}}</td> + <td>{{CompatNo}}</td> + </tr> + <tr> + <td><code>mozGetAsFile()</code> {{non-standard_inline}} {{deprecated_inline}}</td> + <td>{{CompatNo}}</td> + <td>{{CompatNo}}</td> + <td>{{CompatNo}}</td> + <td>{{CompatGeckoMobile('2')}}</td> + <td>{{CompatNo}}</td> + <td>{{CompatNo}}</td> + <td>{{CompatNo}}</td> + </tr> + <tr> + <td><code>captureStream() </code>{{experimental_inline}}</td> + <td>{{CompatNo}}</td> + <td>{{CompatNo}}</td> + <td>{{CompatNo}}</td> + <td>{{CompatGeckoMobile('41')}}</td> + <td>{{CompatNo}}</td> + <td>{{CompatNo}}</td> + <td>{{CompatNo}}</td> + </tr> + <tr> + <td><code>transferControlToOffscreen()</code> {{experimental_inline}}</td> + <td>{{CompatNo}}</td> + <td>{{CompatNo}}</td> + <td>{{CompatNo}}</td> + <td>{{CompatGeckoMobile(44)}} [3]</td> + <td>{{CompatNo}}</td> + <td>{{CompatNo}}</td> + <td>{{CompatNo}}</td> + </tr> + </tbody> +</table> +</div> + +<p>[1] Opera Mini 5.0 and later has partial support.</p> + +<p>[2] Support for the third parameter, has been added in Gecko 25 only: when used with the <code>"image/jpeg"</code> type, this argument specifies the image quality.</p> + +<p>[3] This feature is behind a feature preference setting. In about:config, set <code>gfx.offscreencanvas.enabled</code> to <code>true</code>.</p> + +<h2 id="See_also">See also</h2> + +<ul> + <li>HTML element implementing this interface: {{HTMLElement("canvas")}}.</li> +</ul> |