<?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE html> <html lang="en"> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> <!-- canvas.qdoc --> <title>Qt Quick Examples - Canvas | Qt Quick 5.9</title> <link rel="stylesheet" type="text/css" href="style/offline-simple.css" /> <script type="text/javascript"> document.getElementsByTagName("link").item(0).setAttribute("href", "style/offline.css"); // loading style sheet breaks anchors that were jumped to before // so force jumping to anchor again setTimeout(function() { var anchor = location.hash; // need to jump to different anchor first (e.g. none) location.hash = "#"; setTimeout(function() { location.hash = anchor; }, 0); }, 0); </script> </head> <body> <div class="header" id="qtdocheader"> <div class="main"> <div class="main-rounded"> <div class="navigationbar"> <table><tr> <td >Qt 5.9</td><td ><a href="qtquick-index.html">Qt Quick</a></td><td >Qt Quick Examples - Canvas</td></tr></table><table class="buildversion"><tr> <td id="buildversion" width="100%" align="right">Qt 5.9.4 Reference Documentation</td> </tr></table> </div> </div> <div class="content"> <div class="line"> <div class="content mainContent"> <div class="sidebar"> <div class="toc"> <h3><a name="toc">Contents</a></h3> <ul> <li class="level1"><a href="#running-the-example">Running the Example</a></li> <li class="level1"><a href="#red-heart">Red Heart</a></li> <li class="level1"><a href="#talk-bubble">Talk Bubble</a></li> <li class="level1"><a href="#squircle">Squircle</a></li> <li class="level1"><a href="#rounded-rectangle">Rounded Rectangle</a></li> <li class="level1"><a href="#smile-face">Smile Face</a></li> <li class="level1"><a href="#clip">Clip</a></li> <li class="level1"><a href="#tiger">Tiger</a></li> </ul> </div> <div class="sidebar-content" id="sidebar-content"></div></div> <h1 class="title">Qt Quick Examples - Canvas</h1> <span class="subtitle"></span> <!-- $$$canvas-description --> <div class="descr"> <a name="details"></a> <p class="centerAlign"><img src="images/qml-canvas-example.png" alt="" /></p><p><i>Canvas</i> is a collection of small QML examples relating to the <a href="qml-qtquick-canvas.html">Canvas</a> type. Each example is a small QML file emphasizing a particular type or feature.</p> <a name="running-the-example"></a> <h2 id="running-the-example">Running the Example</h2> <p>To run the example from Qt Creator, open the <b>Welcome</b> mode and select the example from <b>Examples</b>. For more information, visit Building and Running an Example.</p> <a name="red-heart"></a> <h2 id="red-heart">Red Heart</h2> <p><i>Red heart</i> uses the bezier curve API to stroke and fill a red heart.</p> <pre class="qml"> <span class="name">ctx</span>.<span class="name">beginPath</span>(); <span class="name">ctx</span>.<span class="name">moveTo</span>(<span class="number">75</span>,<span class="number">40</span>); <span class="name">ctx</span>.<span class="name">bezierCurveTo</span>(<span class="number">75</span>,<span class="number">37</span>,<span class="number">70</span>,<span class="number">25</span>,<span class="number">50</span>,<span class="number">25</span>); <span class="name">ctx</span>.<span class="name">bezierCurveTo</span>(<span class="number">20</span>,<span class="number">25</span>,<span class="number">20</span>,<span class="number">62.5</span>,<span class="number">20</span>,<span class="number">62.5</span>); <span class="name">ctx</span>.<span class="name">bezierCurveTo</span>(<span class="number">20</span>,<span class="number">80</span>,<span class="number">40</span>,<span class="number">102</span>,<span class="number">75</span>,<span class="number">120</span>); <span class="name">ctx</span>.<span class="name">bezierCurveTo</span>(<span class="number">110</span>,<span class="number">102</span>,<span class="number">130</span>,<span class="number">80</span>,<span class="number">130</span>,<span class="number">62.5</span>); <span class="name">ctx</span>.<span class="name">bezierCurveTo</span>(<span class="number">130</span>,<span class="number">62.5</span>,<span class="number">130</span>,<span class="number">25</span>,<span class="number">100</span>,<span class="number">25</span>); <span class="name">ctx</span>.<span class="name">bezierCurveTo</span>(<span class="number">85</span>,<span class="number">25</span>,<span class="number">75</span>,<span class="number">37</span>,<span class="number">75</span>,<span class="number">40</span>); <span class="name">ctx</span>.<span class="name">closePath</span>(); </pre> <a name="talk-bubble"></a> <h2 id="talk-bubble">Talk Bubble</h2> <p><i>Talk bubble</i> uses the quadraticCurveTo() API to stroke and fill a customized talk bubble:</p> <pre class="qml"> <span class="name">ctx</span>.<span class="name">beginPath</span>(); <span class="name">ctx</span>.<span class="name">moveTo</span>(<span class="number">75</span>,<span class="number">25</span>); <span class="name">ctx</span>.<span class="name">quadraticCurveTo</span>(<span class="number">25</span>,<span class="number">25</span>,<span class="number">25</span>,<span class="number">62.5</span>); <span class="name">ctx</span>.<span class="name">quadraticCurveTo</span>(<span class="number">25</span>,<span class="number">100</span>,<span class="number">50</span>,<span class="number">100</span>); <span class="name">ctx</span>.<span class="name">quadraticCurveTo</span>(<span class="number">50</span>,<span class="number">120</span>,<span class="number">30</span>,<span class="number">125</span>); <span class="name">ctx</span>.<span class="name">quadraticCurveTo</span>(<span class="number">60</span>,<span class="number">120</span>,<span class="number">65</span>,<span class="number">100</span>); <span class="name">ctx</span>.<span class="name">quadraticCurveTo</span>(<span class="number">125</span>,<span class="number">100</span>,<span class="number">125</span>,<span class="number">62.5</span>); <span class="name">ctx</span>.<span class="name">quadraticCurveTo</span>(<span class="number">125</span>,<span class="number">25</span>,<span class="number">75</span>,<span class="number">25</span>); <span class="name">ctx</span>.<span class="name">closePath</span>(); </pre> <p>This example also demonstrates the fillText() API:</p> <pre class="qml"> <span class="name">ctx</span>.<span class="name">fillStyle</span> <span class="operator">=</span> <span class="string">"white"</span>; <span class="name">ctx</span>.<span class="name">font</span> <span class="operator">=</span> <span class="string">"bold 17px sans-serif"</span>; <span class="name">ctx</span>.<span class="name">fillText</span>(<span class="string">"Qt Quick"</span>, <span class="number">40</span>, <span class="number">70</span>); </pre> <a name="squircle"></a> <h2 id="squircle">Squircle</h2> <p><i>Squircle</i> uses a collection of simple moveTo() and lineTo() path APIs to draw a smooth squircle.</p> <a name="rounded-rectangle"></a> <h2 id="rounded-rectangle">Rounded Rectangle</h2> <p><i>Rounded rectangle</i> uses a collection of lineTo() and arcTo() path APIs to draw a rounded rectangle.</p> <a name="smile-face"></a> <h2 id="smile-face">Smile Face</h2> <p><i>Smile face</i> uses several paths to draw and fill a smiling face.</p> <a name="clip"></a> <h2 id="clip">Clip</h2> <p><i>Clip</i> uses the clip API to clip a given image.</p> <pre class="qml"> <span class="name">ctx</span>.<span class="name">clip</span>(); <span class="name">ctx</span>.<span class="name">drawImage</span>(<span class="name">canvas</span>.<span class="name">imagefile</span>, <span class="number">0</span>, <span class="number">0</span>); </pre> <a name="tiger"></a> <h2 id="tiger">Tiger</h2> <p><i>Tiger</i> uses the SVG path API to draw a tiger with a collection of SVG path strings.</p> <pre class="qml"> <span class="keyword">for</span> (<span class="keyword">var</span> <span class="name">i</span> = <span class="number">0</span>; <span class="name">i</span> <span class="operator"><</span> <span class="name">Tiger</span>.<span class="name">tiger</span>.<span class="name">length</span>; i++) { <span class="keyword">if</span> (<span class="name">Tiger</span>.<span class="name">tiger</span>[<span class="name">i</span>].<span class="name">width</span> <span class="operator">!=</span> <span class="name">undefined</span>) <span class="name">ctx</span>.<span class="name">lineWidth</span> <span class="operator">=</span> <span class="name">Tiger</span>.<span class="name">tiger</span>[<span class="name">i</span>].<span class="name">width</span>; <span class="keyword">if</span> (<span class="name">Tiger</span>.<span class="name">tiger</span>[<span class="name">i</span>].<span class="name">path</span> <span class="operator">!=</span> <span class="name">undefined</span>) <span class="name">ctx</span>.<span class="name">path</span> <span class="operator">=</span> <span class="name">Tiger</span>.<span class="name">tiger</span>[<span class="name">i</span>].<span class="name">path</span>; <span class="keyword">if</span> (<span class="name">Tiger</span>.<span class="name">tiger</span>[<span class="name">i</span>].<span class="name">fill</span> <span class="operator">!=</span> <span class="name">undefined</span>) { <span class="name">ctx</span>.<span class="name">fillStyle</span> <span class="operator">=</span> <span class="name">Tiger</span>.<span class="name">tiger</span>[<span class="name">i</span>].<span class="name">fill</span>; <span class="name">ctx</span>.<span class="name">fill</span>(); } <span class="keyword">if</span> (<span class="name">Tiger</span>.<span class="name">tiger</span>[<span class="name">i</span>].<span class="name">stroke</span> <span class="operator">!=</span> <span class="name">undefined</span>) { <span class="name">ctx</span>.<span class="name">strokeStyle</span> <span class="operator">=</span> <span class="name">Tiger</span>.<span class="name">tiger</span>[<span class="name">i</span>].<span class="name">stroke</span>; <span class="name">ctx</span>.<span class="name">stroke</span>(); } } </pre> <p>Files:</p> <ul> <li><a href="qtquick-canvas-canvas-qml.html">canvas/canvas.qml</a></li> <li><a href="qtquick-canvas-beziercurve-beziercurve-qml.html">canvas/bezierCurve/bezierCurve.qml</a></li> <li><a href="qtquick-canvas-clip-clip-qml.html">canvas/clip/clip.qml</a></li> <li><a href="qtquick-canvas-quadraticcurveto-quadraticcurveto-qml.html">canvas/quadraticCurveTo/quadraticCurveTo.qml</a></li> <li><a href="qtquick-canvas-roundedrect-roundedrect-qml.html">canvas/roundedrect/roundedrect.qml</a></li> <li><a href="qtquick-canvas-smile-smile-qml.html">canvas/smile/smile.qml</a></li> <li><a href="qtquick-canvas-squircle-squircle-qml.html">canvas/squircle/squircle.qml</a></li> <li><a href="qtquick-canvas-tiger-tiger-js.html">canvas/tiger/tiger.js</a></li> <li><a href="qtquick-canvas-tiger-tiger-qml.html">canvas/tiger/tiger.qml</a></li> <li><a href="qtquick-canvas-main-cpp.html">canvas/main.cpp</a></li> <li><a href="qtquick-canvas-canvas-pro.html">canvas/canvas.pro</a></li> <li><a href="qtquick-canvas-canvas-qrc.html">canvas/canvas.qrc</a></li> </ul> </div> <!-- @@@canvas --> </div> </div> </div> </div> </div> <div class="footer"> <p> <acronym title="Copyright">©</acronym> 2017 The Qt Company Ltd. Documentation contributions included herein are the copyrights of their respective owners.<br> The documentation provided herein is licensed under the terms of the <a href="http://www.gnu.org/licenses/fdl.html">GNU Free Documentation License version 1.3</a> as published by the Free Software Foundation.<br> Qt and respective logos are trademarks of The Qt Company Ltd. in Finland and/or other countries worldwide. All other trademarks are property of their respective owners. </p> </div> </body> </html>