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      <title>Level of Detail options</title>
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      <div class="title_topic2" id="xps10_pagetitle">Level of Detail options</div>
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      <p class="para_topic">The level of detail section of the configuration file contains the tessellation information for each level of detail (LOD) in the file. There is a set of LOD options for each LOD. The number specified for the &quot;numLODs&quot; setup option determines the number of sets of LODs in the configuration file.</p>
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               <p class="para_th">Option</p>
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               <p class="para_th">Description</p>
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               <p class="para_th">Values/Example</p>
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               <p class="para_td">LOD</p>
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               <p class="para_td">Contains the keyword indicating the beginning of a LOD block, the number of the level of details, and a &quot;{&quot; (left brace).</p>
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               <p class="para_td">For example, LOD &quot;1&quot; {.</p>
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               <p class="para_td">level</p>
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               <p class="para_td">Enables you to reiterate how many levels of detail your translations process.</p>
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               <p class="para_td">For example, if there are three LODs, this option is repeated three times, each with a different LOD.</p>
               <p class="para_td">level =1, level=2, level=3</p>
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               <p class="para_td">chordal</p>
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               <p class="para_td">Defines the maximum absolute distance that a line segment can deviate from the smooth curve it is approximating.</p>
               <p class="para_td">This value produces the levels of detail representing each part. It specifies polygonal approximations of models defined with curved surfaces.</p>
               <p class="para_td">In the following figure, the arrows show the chordal distance:</p>
               <p align="center"><img align="bottom" src="graphics/CHORDAL.GIF"></p>
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               <p class="para_td">For example, chordal = 0.001</p>
               <p class="para_td">The round object below has a small hole through the center of it. If the translator tessellates the object with only the chordal parameter, the polygons in the large surface area of the object follow the curves much better than the polygons in the small surface area (the center). If the translator tessellates the object with only the angular parameter, the polygons in the small surface area (the center) of the object follow the curves much better than the polygons in the large surface area.</p>
               <p class="para_td">For best results, use both chordal and angular parameters. The chordal value affects primarily the larger features of the model, and the angular value primarily affects the smaller features of the model.</p>
               <p class="para_td">The first figure below shows the round object only with chordal parameters applied. The second figure shows the round object with both chordal and angular parameters applied.</p>
               <p align="center"><img align="bottom" src="graphics/chordalonly.gif"></p>
               <p align="center"><img align="bottom" src="graphics/chordalangular.gif"></p>
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               <p class="para_td">angular</p>
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               <p class="para_td">Limits the absolute maximum angle between two adjacent line segments in a curve approximation.</p>
               <p class="para_td">For example, angular = 25</p>
               <p class="para_td">This value produces the levels of detail representing each part. It specifies polygonal approximations of models defined with curved surfaces.</p>
               <p class="para_td">In the following figure, the arrow shows the angle area:</p>
               <p align="center"><img align="bottom" src="graphics/angle.gif"></p>
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               <p class="para_td">The round object below has a small hole through the center of it. If the translator tessellates the object with only the angular parameter, the polygons that define the hole follow the surface much better than the polygons that define the perimeter. If the translator tessellates the object with only the chordal parameter, the polygons along the perimeter of the object follow the curves much better than the polygons that define the hole.</p>
               <p class="para_td">For best results, use both chordal and angular parameters. The chordal value affects primarily the larger features of the model, and the angular value primarily affects the smaller features of the model.</p>
               <p class="para_td">The first figure below shows the round object only with angular parameters applied.</p>
               <p align="center"><img align="bottom" src="graphics/angularonly.gif"></p>
               <p class="para_td">The second figure shows the round object with both angular and chordal parameters applied.</p>
               <p align="center"><img align="bottom" src="graphics/chordalangular.gif"></p>
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               <p class="para_td">length</p>
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               <p class="para_td">Specifies the absolute length of the tessellation chords.</p>
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               <p class="para_td">Length = 1</p>
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               <p class="para_td">label</p>
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               <p class="para_td">Specifies the name for a particular LOD.</p>
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                           <p class="para_note_body">This option is not set in the default configuration file shipped with NX.</p>
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               <p class="para_td">label = &lt;label name&gt;</p>
               <p class="para_td">For example, Label = GridTess</p>
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               <p class="para_td">featureSuppression</p>
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               <p class="para_td">Suppresses holes and arcs smaller than the specified number.</p>
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               <p class="para_td">featureSuppression = 0</p>
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               <p class="para_td">simplify</p>
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               <p class="para_td">Specifies a percentage as a minimum level of simplification for the model, relative to the first level of detail.</p>
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                           <p class="para_note_body">The simplification for the first LOD should be left at 1.0 (100%), because you want to keep the highest level of detail possible for that LOD.</p>
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               <p class="para_td">simplify = .060</p>
               <p class="para_td">A model with 100,000 polygons for the first level of detail has a specified simplify value of 0.60 (sixty percent) for the second level of detail. </p>
               <p class="para_td">The translator translates the model and checks the resulting model to see if it has 60,000 or fewer polygons (sixty percent of the original model).</p>
               <p class="para_td">If there are more than 60,000 polygons, the translator continues to simplify the model as necessary until the number of polygons meets the sixty percent criteria. </p>
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               <p class="para_td">advCompressionLevel</p>
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               <p class="para_td"></p>
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               <p class="para_td">close brace</p>
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               <p class="para_td">The right brace that indicates the end of the section.</p>
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               <p class="para_td">}</p>
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