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<td >Qt 5.12</td><td ><a href="qt3d-index.html">Qt 3D</a></td><td ><a href="qt3d-cpp.html">C++ Classes</a></td><td >QBufferDataGenerator</td></tr></table><table class="buildversion"><tr>
<td id="buildversion" width="100%" align="right"><a href="qt3d-index.html">Qt 5.12.2 Reference Documentation</a></td>
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<h3><a name="toc">Contents</a></h3>
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<li class="level1"><a href="#public-functions">Public Functions</a></li>
<li class="level1"><a href="#details">Detailed Description</a></li>
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<h1 class="title">QBufferDataGenerator Class</h1>
<span class="small-subtitle">(<a href="qt3drender-qbufferdatagenerator.html">Qt3DRender::QBufferDataGenerator</a>)<br/></span>
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<p>Provides a mechanism to generate buffer data from a job. <a href="#details">More...</a></p>
<!-- @@@QBufferDataGenerator -->
<div class="table"><table class="alignedsummary">
<tr><td class="memItemLeft rightAlign topAlign"> Header:</td><td class="memItemRight bottomAlign"> <span class="preprocessor">#include <QBufferDataGenerator></span>
</td></tr><tr><td class="memItemLeft rightAlign topAlign"> qmake:</td><td class="memItemRight bottomAlign"> QT += 3drender</td></tr><tr><td class="memItemLeft rightAlign topAlign"> Inherits:</td><td class="memItemRight bottomAlign"> <a href="qt3drender-qabstractfunctor.html">Qt3DRender::QAbstractFunctor</a></td></tr></table></div><ul>
<li><a href="qt3drender-qbufferdatagenerator-members.html">List of all members, including inherited members</a></li>
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<a name="public-functions"></a>
<h2 id="public-functions">Public Functions</h2>
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<tr><td class="memItemLeft rightAlign topAlign"> virtual </td><td class="memItemRight bottomAlign"><b><a href="qt3drender-qbufferdatagenerator.html#dtor.QBufferDataGenerator">~QBufferDataGenerator</a></b>()</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> virtual QByteArray </td><td class="memItemRight bottomAlign"><b><a href="qt3drender-qbufferdatagenerator.html#operator-28-29">operator()</a></b>() = 0</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> virtual bool </td><td class="memItemRight bottomAlign"><b><a href="qt3drender-qbufferdatagenerator.html#operator-eq-eq">operator==</a></b>(const Qt3DRender::QBufferDataGenerator &<i>other</i>) const = 0</td></tr>
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<li class="fn">2 public functions inherited from <a href="qt3drender-qabstractfunctor.html#public-functions">Qt3DRender::QAbstractFunctor</a></li>
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<a name="details"></a>
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<h2 id="details">Detailed Description</h2>
<p>Provides a mechanism to generate buffer data from a job.</p>
<p>The <a href="qt3drender-qbufferdatagenerator.html">Qt3DRender::QBufferDataGenerator</a> should be subclassed to provide a way to fill the data of a <a href="qt3drender-qbuffer.html">Qt3DRender::QBuffer</a>. Such functors are executed at runtime in a Qt 3D job (likely in parallel with many other jobs). When providing a functor you must implement the <a href="qt3drender-qbufferdatagenerator.html#operator-28-29">operator</a>() which will be called to generate the actual data. You must make sure that you have stored copies of anything you might need for it to execute properly. You should also implement the operator==. It will be used to compare with other functors and based on that allow the renderer to decide if a new functor should be executed or not.</p>
<p><b>Note: </b>functors are useful when you can build data from a few set of attributes (e.g: building a sphere from a radius property). If you already have access to the buffer data, using Qt3DRender::QBuffer::setData() is likely more efficient.</p><pre class="cpp">
<span class="type">QByteArray</span> createSphereMeshVertexData(<span class="type">float</span> radius<span class="operator">,</span> <span class="type">int</span> rings<span class="operator">,</span> <span class="type">int</span> slices)
{
<span class="operator">.</span><span class="operator">.</span><span class="operator">.</span>
}
<span class="keyword">class</span> SphereVertexDataFunctor : <span class="keyword">public</span> <span class="type"><a href="qt3drender-qbufferdatagenerator.html">QBufferDataGenerator</a></span>
{
<span class="keyword">public</span>:
SphereVertexDataFunctor(<span class="type">int</span> rings<span class="operator">,</span> <span class="type">int</span> slices<span class="operator">,</span> <span class="type">float</span> radius)
: m_rings(rings)
<span class="operator">,</span> m_slices(slices)
<span class="operator">,</span> m_radius(radius)
{}
<span class="type">QByteArray</span> <span class="keyword">operator</span> ()() override
{
<span class="keyword">return</span> createSphereMeshVertexData(m_radius<span class="operator">,</span> m_rings<span class="operator">,</span> m_slices);
}
bool <span class="keyword">operator</span> <span class="operator">=</span><span class="operator">=</span>(<span class="keyword">const</span> <span class="type"><a href="qt3drender-qbufferdatagenerator.html">QBufferDataGenerator</a></span> <span class="operator">&</span>other) <span class="keyword">const</span> override
{
<span class="keyword">const</span> SphereVertexDataFunctor <span class="operator">*</span>otherFunctor <span class="operator">=</span> functor_cast<span class="operator"><</span>SphereVertexDataFunctor<span class="operator">></span>(<span class="operator">&</span>other);
<span class="keyword">if</span> (otherFunctor <span class="operator">!</span><span class="operator">=</span> nullptr)
<span class="keyword">return</span> (otherFunctor<span class="operator">-</span><span class="operator">></span>m_rings <span class="operator">=</span><span class="operator">=</span> m_rings <span class="operator">&</span><span class="operator">&</span>
otherFunctor<span class="operator">-</span><span class="operator">></span>m_slices <span class="operator">=</span><span class="operator">=</span> m_slices <span class="operator">&</span><span class="operator">&</span>
otherFunctor<span class="operator">-</span><span class="operator">></span>m_radius <span class="operator">=</span><span class="operator">=</span> m_radius);
<span class="keyword">return</span> <span class="keyword">false</span>;
}
QT3D_FUNCTOR(SphereVertexDataFunctor)
<span class="keyword">private</span>:
<span class="type">int</span> m_rings;
<span class="type">int</span> m_slices;
<span class="type">float</span> m_radius;
};
</pre>
<p>The <a href="qt3drender-qabstractfunctor.html#QT3D_FUNCTOR">QT3D_FUNCTOR</a> macro should be added when subclassing. This allows you to use <a href="qt3drender-qabstractfunctor.html#functor_cast">functor_cast</a> in your comparison operator to make sure that the other functor is of the same type as the one your are trying to compare against.</p>
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<h2>Member Function Documentation</h2>
<!-- $$$~QBufferDataGenerator[overload1]$$$~QBufferDataGenerator -->
<h3 class="fn" id="dtor.QBufferDataGenerator"><a name="dtor.QBufferDataGenerator"></a><code>[virtual] </code>QBufferDataGenerator::<span class="name">~QBufferDataGenerator</span>()</h3>
<p>Destroys the instance of QBufferDataGenerator. The destructor is virtual.</p><!-- @@@~QBufferDataGenerator -->
<!-- $$$operator()[overload1]$$$operator() -->
<h3 class="fn" id="operator-28-29"><a name="operator-28-29"></a><code>[pure virtual] </code><span class="type">QByteArray</span> QBufferDataGenerator::<span class="name">operator()</span>()</h3>
<!-- @@@operator() -->
<!-- $$$operator==[overload1]$$$operator==constQt3DRender::QBufferDataGenerator& -->
<h3 class="fn" id="operator-eq-eq"><a name="operator-eq-eq"></a><code>[pure virtual] </code><span class="type">bool</span> QBufferDataGenerator::<span class="name">operator==</span>(const <span class="type"><a href="qt3drender-qbufferdatagenerator.html">Qt3DRender::QBufferDataGenerator</a></span> &<i>other</i>) const</h3>
<!-- @@@operator== -->
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