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      <title>Use Midpoint Sampling</title>
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      <div class="title_topic6" id="xps10_pagetitle"> Use Midpoint Sampling</div>
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               <p class="para_td"> <a class="links" href="javascript:void(0)" onclick="top.openFile('visualizing_a_part/vie_vis_hq_ov.html');return(false);">Overview</a></p>
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               <p class="para_td"> <a class="links" href="javascript:void(0)" onclick="top.openFile('visualizing_a_part/vie_vis_hq_ht.html');return(false);">How To</a></p>
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               <p class="para_td"> <a class="links" href="javascript:void(0)" onclick="top.openFile('visualizing_a_part/vie_vis_hqi_op.html');return(false);">Dialog Options</a></p>
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      </table><br><p class="para_topic"> The Midpoint Sampling toggle is used to change exactly how light is applied to a surface. Depending on the geometry of the scene the midpoint sampling option can improve the output image and avoid some cases where light seems to &quot;leak&quot; through under a surface.</p>
      <p class="para_topic"> There are situations where the resulting scene has bright or dark regions that seem to bleed through walls or objects on a floor. Switching from End-point to Mid-point sampling can clean-up some of these effects. The reverse can also be true, where mid point sampling causes strange looking highlight or shadow areas, an end point sampling is better. The technical detail is whether radiosity samples triangles at the end points of the triangles (default) or at the midpoint of the edges of the triangle.</p>
      <p class="para_topic"> The default end point sample works fine for 75% of the cases. If there are small triangular regions that appear too bright or too dark, try the Mid-Point sampling method.  </p>
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