<?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE html> <html lang="en"> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> <!-- qsgnode.cpp --> <title>QSGOpacityNode Class | 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 ><a href="qtquick-module.html">C++ Classes</a></td><td >QSGOpacityNode</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="#public-functions">Public Functions</a></li> <li class="level1"><a href="#details">Detailed Description</a></li> </ul> </div> <div class="sidebar-content" id="sidebar-content"></div></div> <h1 class="title">QSGOpacityNode Class</h1> <!-- $$$QSGOpacityNode-brief --> <p>The <a href="qsgopacitynode.html">QSGOpacityNode</a> class is used to change opacity of nodes. <a href="#details">More...</a></p> <!-- @@@QSGOpacityNode --> <div class="table"><table class="alignedsummary"> <tr><td class="memItemLeft rightAlign topAlign"> Header:</td><td class="memItemRight bottomAlign"> <span class="preprocessor">#include <QSGOpacityNode></span> </td></tr><tr><td class="memItemLeft rightAlign topAlign"> qmake:</td><td class="memItemRight bottomAlign"> QT += quick</td></tr><tr><td class="memItemLeft rightAlign topAlign"> Inherits:</td><td class="memItemRight bottomAlign"> <a href="qsgnode.html">QSGNode</a></td></tr></table></div><ul> <li><a href="qsgopacitynode-members.html">List of all members, including inherited members</a></li> </ul> <a name="public-functions"></a> <h2 id="public-functions">Public Functions</h2> <div class="table"><table class="alignedsummary"> <tr><td class="memItemLeft rightAlign topAlign"> </td><td class="memItemRight bottomAlign"><b><a href="qsgopacitynode.html#QSGOpacityNode">QSGOpacityNode</a></b>()</td></tr> <tr><td class="memItemLeft rightAlign topAlign"> </td><td class="memItemRight bottomAlign"><b><a href="qsgopacitynode.html#dtor.QSGOpacityNode">~QSGOpacityNode</a></b>()</td></tr> <tr><td class="memItemLeft rightAlign topAlign"> qreal </td><td class="memItemRight bottomAlign"><b><a href="qsgopacitynode.html#opacity">opacity</a></b>() const</td></tr> <tr><td class="memItemLeft rightAlign topAlign"> void </td><td class="memItemRight bottomAlign"><b><a href="qsgopacitynode.html#setOpacity">setOpacity</a></b>(qreal <i>opacity</i>)</td></tr> </table></div> <ul> <li class="fn">20 public functions inherited from <a href="qsgnode.html#public-functions">QSGNode</a></li> </ul> <a name="details"></a> <!-- $$$QSGOpacityNode-description --> <div class="descr"> <h2 id="details">Detailed Description</h2> <p>The <a href="qsgopacitynode.html">QSGOpacityNode</a> class is used to change opacity of nodes.</p> <p>Opacity applies to its subtree and can be nested. Multiple opacity nodes will be accumulated by multiplying their opacity. The accumulation happens as part of the rendering.</p> <p>When nested opacity gets below a certain threshold, the subtree might be marked as blocked, causing <a href="qsgnode.html#isSubtreeBlocked">isSubtreeBlocked</a>() to return true. This is done for performance reasons.</p> <p><b>Note: </b>All classes with QSG prefix should be used solely on the scene graph's rendering thread. See <a href="qtquick-visualcanvas-scenegraph.html#scene-graph-and-rendering">Scene Graph and Rendering</a> for more information.</p></div> <!-- @@@QSGOpacityNode --> <div class="func"> <h2>Member Function Documentation</h2> <!-- $$$QSGOpacityNode[overload1]$$$QSGOpacityNode --> <h3 class="fn" id="QSGOpacityNode"><a name="QSGOpacityNode"></a>QSGOpacityNode::<span class="name">QSGOpacityNode</span>()</h3> <p>Constructs an opacity node with a default opacity of 1.</p> <p>Opacity accumulates downwards in the scene graph so a node with two <a href="qsgopacitynode.html">QSGOpacityNode</a> instances above it, both with opacity of 0.5, will have effective opacity of 0.25.</p> <p>The default opacity of nodes is 1.</p> <!-- @@@QSGOpacityNode --> <!-- $$$~QSGOpacityNode[overload1]$$$~QSGOpacityNode --> <h3 class="fn" id="dtor.QSGOpacityNode"><a name="dtor.QSGOpacityNode"></a>QSGOpacityNode::<span class="name">~QSGOpacityNode</span>()</h3> <p>Deletes the opacity node.</p> <!-- @@@~QSGOpacityNode --> <!-- $$$opacity[overload1]$$$opacity --> <h3 class="fn" id="opacity"><a name="opacity"></a><span class="type">qreal</span> QSGOpacityNode::<span class="name">opacity</span>() const</h3> <p>Returns this opacity node's opacity.</p> <p><b>See also </b><a href="qsgopacitynode.html#setOpacity">setOpacity</a>().</p> <!-- @@@opacity --> <!-- $$$setOpacity[overload1]$$$setOpacityqreal --> <h3 class="fn" id="setOpacity"><a name="setOpacity"></a><span class="type">void</span> QSGOpacityNode::<span class="name">setOpacity</span>(<span class="type">qreal</span> <i>opacity</i>)</h3> <p>Sets the opacity of this node to <i>opacity</i>.</p> <p>Before rendering the graph, the renderer will do an update pass over the subtree to propagate the opacity to its children.</p> <p>The value will be bounded to the range 0 to 1.</p> <p><b>See also </b><a href="qsgopacitynode.html#opacity">opacity</a>().</p> <!-- @@@setOpacity --> </div> </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>