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      <title>View Frustum Culling</title>
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      <div class="title_topic4" id="xps10_pagetitle">View Frustum Culling</div>
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      <p class="para_topic">View Frustum Culling refers to the technique of reducing a scene's complexity by pre-determining which objects are outside the visibile portion of the view and ignoring those objects when passing the scene data to the graphics hardware. While the graphics hardware would &quot;cull&quot; the objects that are outside the view if they were also passed as part of the scene, the data set that represents an object can be comprised of many points and vectors. It is oftentimes more efficient to preprocess the object's position relative to the view than it is to pass all the data representing the object to the hardware.</p>
      <p class="para_topic">By default, this option is On. In most cases, you will want the option on. You may want to turn it off for degenerate cases that the algorithm does not adequately deal with.</p>
      <p class="para_topic">Frustum is a term which describes a pyramid with the top cut off by a plane that is parallel to the back plane of the pyramid. This conceptually describes the viewing volume when perspective is enabled as it is bounded by a front and back clip plane. When a parallel projection is used, the view frustum becomes a cube. The term frustum however still applies to this shape as well.</p>
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