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<td >Qt 5.12</td><td ><a href="qt3d-index.html">Qt 3D</a></td><td ><a href="qt3d-qml.html">QML Types</a></td><td >PointLight QML Type</td></tr></table><table class="buildversion"><tr>
<td id="buildversion" width="100%" align="right"><a href="qt3d-index.html">Qt 5.12.6 Reference Documentation</a></td>
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<h3><a name="toc">Contents</a></h3>
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<li class="level1"><a href="#properties">Properties</a></li>
<li class="level1"><a href="#details">Detailed Description</a></li>
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<h1 class="title">PointLight QML Type</h1>
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<p>Encapsulate a Point Light object in a Qt 3D scene. <a href="#details">More...</a></p>
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<tr><td class="memItemLeft rightAlign topAlign"> Import Statement:</td><td class="memItemRight bottomAlign"> import Qt3D.Render 2.12</td></tr><tr><td class="memItemLeft rightAlign topAlign"> Since:</td><td class="memItemRight bottomAlign"> Qt 5.5</td></tr><tr><td class="memItemLeft rightAlign topAlign"> Instantiates:</td><td class="memItemRight bottomAlign"> <a href="qml-qt3d-render-pointlight.html"><a href="qt3drender-qpointlight.html">QPointLight</a></td></tr></table></div><ul>
<li><a href="qml-qt3d-render-pointlight-members.html">List of all members, including inherited members</a></li>
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<h2 id="properties">Properties</h2>
<ul>
<li class="fn"><b><b><a href="qml-qt3d-render-pointlight.html#constantAttenuation-prop">constantAttenuation</a></b></b> : float</li>
<li class="fn"><b><b><a href="qml-qt3d-render-pointlight.html#linearAttenuation-prop">linearAttenuation</a></b></b> : float</li>
<li class="fn"><b><b><a href="qml-qt3d-render-pointlight.html#quadraticAttenuation-prop">quadraticAttenuation</a></b></b> : float</li>
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<a name="details"></a>
<h2 id="details">Detailed Description</h2>
<p>A point light is a light source that emits light in all directions, from a single point. Conceptually, this is similar to light given off by a standard light bulb.</p>
<p>A point light uses three attenuation factors to describe how the intensity of the light decreases over distance. These factors are designed to be used together in calcuating total attenuation. For the materials in Qt3D Extras the following formula is used, where distance is the distance from the light to the surface being rendered:</p>
<pre class="cpp">
totalAttenuation <span class="operator">=</span> <span class="number">1.0</span> <span class="operator">/</span> (constantAttenuation <span class="operator">+</span> (linearAttenuation <span class="operator">*</span> distance) <span class="operator">+</span> (quadraticAttenuation <span class="operator">*</span> distance <span class="operator">*</span> distance));
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<p>Custom materials may choose to interpret these factors differently.</p>
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<h2>Property Documentation</h2>
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<a name="constantAttenuation-prop"></a><span class="name">constantAttenuation</span> : <span class="type">float</span></p></td></tr>
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</div><div class="qmldoc"><p>Specifies the constant attenuation of the point light</p>
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<tr valign="top" class="odd" id="linearAttenuation-prop">
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<a name="linearAttenuation-prop"></a><span class="name">linearAttenuation</span> : <span class="type">float</span></p></td></tr>
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</div><div class="qmldoc"><p>Specifies the linear attenuation of the point light</p>
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<tr valign="top" class="odd" id="quadraticAttenuation-prop">
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<a name="quadraticAttenuation-prop"></a><span class="name">quadraticAttenuation</span> : <span class="type">float</span></p></td></tr>
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</div><div class="qmldoc"><p>Specifies the quadratic attenuation of the point light</p>
</div></div><!-- @@@quadraticAttenuation -->
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