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<!-- OpacityMask.qml -->
  <title>OpacityMask QML Type | Qt Graphical Effects 5.11</title>
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<td ><a href="../qtdoc/index.html">Qt 5.11</a></td><td ><a href="qtgraphicaleffects-index.html">Qt Graphical Effects</a></td><td ><a href="graphicaleffects.html">QML Types</a></td><td >OpacityMask QML Type</td></tr></table><table class="buildversion"><tr>
<td id="buildversion" width="100%" align="right">Qt 5.11.2 Reference Documentation</td>
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<h3><a name="toc">Contents</a></h3>
<ul>
<li class="level1"><a href="#properties">Properties</a></li>
<li class="level1"><a href="#details">Detailed Description</a></li>
<li class="level2"><a href="#example">Example</a></li>
</ul>
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<div class="sidebar-content" id="sidebar-content"></div></div>
<h1 class="title">OpacityMask QML Type</h1>
<span class="subtitle"></span>
<!-- $$$OpacityMask-brief -->
<p>Masks the source item with another item. <a href="#details">More...</a></p>
<!-- @@@OpacityMask -->
<div class="table"><table class="alignedsummary">
<tr><td class="memItemLeft rightAlign topAlign"> Import Statement:</td><td class="memItemRight bottomAlign"> import QtGraphicalEffects 1.0</td></tr><tr><td class="memItemLeft rightAlign topAlign"> Since:</td><td class="memItemRight bottomAlign">  QtGraphicalEffects 1.0</td></tr><tr><td class="memItemLeft rightAlign topAlign"> Inherits:</td><td class="memItemRight bottomAlign"> <p><a href="../qtquick/qml-qtquick-item.html">Item</a></p>
</td></tr></table></div><ul>
<li><a href="qml-qtgraphicaleffects-opacitymask-members.html">List of all members, including inherited members</a></li>
</ul>
<a name="properties"></a>
<h2 id="properties">Properties</h2>
<ul>
<li class="fn"><b><b><a href="qml-qtgraphicaleffects-opacitymask.html#cached-prop">cached</a></b></b> : bool</li>
<li class="fn"><b><b><a href="qml-qtgraphicaleffects-opacitymask.html#invert-prop">invert</a></b></b> : bool</li>
<li class="fn"><b><b><a href="qml-qtgraphicaleffects-opacitymask.html#maskSource-prop">maskSource</a></b></b> : variant</li>
<li class="fn"><b><b><a href="qml-qtgraphicaleffects-opacitymask.html#source-prop">source</a></b></b> : variant</li>
</ul>
<!-- $$$OpacityMask-description -->
<a name="details"></a>
<h2 id="details">Detailed Description</h2>
<div class="table"><table class="generic">
 <thead><tr class="qt-style"><th >Source</th><th >MaskSource</th><th >Effect applied</th></tr></thead>
<tr valign="top" class="odd"><td ><p class="centerAlign"><img src="images/Original_bug.png" alt="" /></p></td><td ><p class="centerAlign"><img src="images/OpacityMask_mask.png" alt="" /></p></td><td ><p class="centerAlign"><img src="images/OpacityMask_bug.png" alt="" /></p></td></tr>
</table></div>
<p><b>Note: </b>This effect is available when running with OpenGL.</p><a name="example"></a>
<h2 id="example">Example</h2>
<p>The following example shows how to apply the effect.</p>
<pre class="qml">

  import QtQuick 2.0
  import QtGraphicalEffects 1.0

  <span class="type"><a href="../qtquick/qml-qtquick-item.html">Item</a></span> {
      <span class="name">width</span>: <span class="number">300</span>
      <span class="name">height</span>: <span class="number">300</span>

      <span class="type"><a href="../qtquick/qml-qtquick-image.html">Image</a></span> {
          <span class="name">id</span>: <span class="name">bug</span>
          <span class="name">source</span>: <span class="string">&quot;images/bug.jpg&quot;</span>
          <span class="name">sourceSize</span>: <span class="name">Qt</span>.<span class="name">size</span>(<span class="name">parent</span>.<span class="name">width</span>, <span class="name">parent</span>.<span class="name">height</span>)
          <span class="name">smooth</span>: <span class="number">true</span>
          <span class="name">visible</span>: <span class="number">false</span>
      }

      <span class="type"><a href="../qtquick/qml-qtquick-image.html">Image</a></span> {
          <span class="name">id</span>: <span class="name">mask</span>
          <span class="name">source</span>: <span class="string">&quot;images/butterfly.png&quot;</span>
          <span class="name">sourceSize</span>: <span class="name">Qt</span>.<span class="name">size</span>(<span class="name">parent</span>.<span class="name">width</span>, <span class="name">parent</span>.<span class="name">height</span>)
          <span class="name">smooth</span>: <span class="number">true</span>
          <span class="name">visible</span>: <span class="number">false</span>
      }

      <span class="type"><a href="qml-qtgraphicaleffects-opacitymask.html">OpacityMask</a></span> {
          <span class="name">anchors</span>.fill: <span class="name">bug</span>
          <span class="name">source</span>: <span class="name">bug</span>
          <span class="name">maskSource</span>: <span class="name">mask</span>
      }
  }

</pre>
<!-- @@@OpacityMask -->
<h2>Property Documentation</h2>
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<div class="table"><table class="qmlname">
<tr valign="top" class="odd" id="cached-prop">
<td class="tblQmlPropNode"><p>
<a name="cached-prop"></a><span class="name">cached</span> : <span class="type"><a href="../qtqml/qml-bool.html">bool</a></span></p></td></tr>
</table></div>
</div><div class="qmldoc"><p>This property allows the effect output pixels to be cached in order to improve the rendering performance.</p>
<p>Every time the source or effect properties are changed, the pixels in the cache must be updated. Memory consumption is increased, because an extra buffer of memory is required for storing the effect output.</p>
<p>It is recommended to disable the cache when the source or the effect properties are animated.</p>
<p>By default, the property is set to <code>false</code>.</p>
<p><b>Note: </b>It is not supported to let the effect include itself, for instance by setting <a href="qml-qtgraphicaleffects-opacitymask.html#maskSource-prop">maskSource</a> to the effect's parent.</p></div></div><!-- @@@cached -->
<br/>
<!-- $$$invert -->
<div class="qmlitem"><div class="qmlproto">
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<tr valign="top" class="odd" id="invert-prop">
<td class="tblQmlPropNode"><p>
<a name="invert-prop"></a><span class="name">invert</span> : <span class="type"><a href="../qtqml/qml-bool.html">bool</a></span></p></td></tr>
</table></div>
</div><div class="qmldoc"><p>This property controls how the alpha values of the sourceMask will behave.</p>
<p>If this property is <code>false</code>, the resulting opacity is the source alpha multiplied with the mask alpha, <code>As * Am</code>.</p>
<p>If this property is <code>true</code>, the resulting opacity is the source alpha multiplied with the inverse of the mask alpha, <code>As * (1 - Am)</code>.</p>
<p>The default is <code>false</code>.</p>
<p>This property was introduced in  Qt 5.7.</p>
</div></div><!-- @@@invert -->
<br/>
<!-- $$$maskSource -->
<div class="qmlitem"><div class="qmlproto">
<div class="table"><table class="qmlname">
<tr valign="top" class="odd" id="maskSource-prop">
<td class="tblQmlPropNode"><p>
<a name="maskSource-prop"></a><span class="name">maskSource</span> : <span class="type"><a href="../qtqml/qml-variant.html">variant</a></span></p></td></tr>
</table></div>
</div><div class="qmldoc"><p>This property defines the item that is going to be used as the mask. The mask item gets rendered into an intermediate pixel buffer and the alpha values from the result are used to determine the source item's pixels visibility in the display.</p>
<div class="table"><table class="generic">
 <thead><tr class="qt-style"><th >Original</th><th >Mask</th><th >Effect applied</th></tr></thead>
<tr valign="top" class="odd"><td ><p class="centerAlign"><img src="images/Original_bug.png" alt="" /></p></td><td ><p class="centerAlign"><img src="images/OpacityMask_mask.png" alt="" /></p></td><td ><p class="centerAlign"><img src="images/OpacityMask_bug.png" alt="" /></p></td></tr>
</table></div>
</div></div><!-- @@@maskSource -->
<br/>
<!-- $$$source -->
<div class="qmlitem"><div class="qmlproto">
<div class="table"><table class="qmlname">
<tr valign="top" class="odd" id="source-prop">
<td class="tblQmlPropNode"><p>
<a name="source-prop"></a><span class="name">source</span> : <span class="type"><a href="../qtqml/qml-variant.html">variant</a></span></p></td></tr>
</table></div>
</div><div class="qmldoc"><p>This property defines the source item that is going to be masked.</p>
<p><b>Note: </b>It is not supported to let the effect include itself, for instance by setting source to the effect's parent.</p></div></div><!-- @@@source -->
<br/>
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