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      <title>Mesh display</title>
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      <div class="title_topic2" id="xps10_pagetitle">Mesh display</div>
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      <p class="para_topic">The <b class="uiTerm">Mesh Display</b> can give you an indication of the success of the meshing process.&nbsp;A successful mesh should evenly cover the entire surface you want flattened. A mesh that overlaps itself or covers the surface more than once is an indication that the mesh is degenerate. If the entire surface is not covered by the mesh in regions of extreme curvature or where the boundary is complicated, a smaller grid size may be in order. The mesh displays with points and lines, depending on how each individual node generates. Two short lines in an L shape will represent most nodes of the mesh.&nbsp;Completing a quadrilateral element of the mesh generates these nodes. The two lines point back to the two neighboring nodes used to generate the new node. Other nodes of the mesh are generated from a single other node, and are represented by a single line. The strings of points emanating in the primary and secondary directions from the base (start) point fall in this category.&nbsp;The start point and some extrapolated or error condition points are displayed as single points. These mesh entities are color coded by the following convention: (number represents fiber angle (unit in degrees).
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               <p class="para_th">Distorted fiber angle (degree)</p>
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               <p class="para_th">Color</p>
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               <p class="para_td">Deviation not calculated</p>
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               <p class="para_td">white</p>
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               <p class="para_td">90 &ndash; 85</p>
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               <p class="para_td">blue</p>
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               <p class="para_td">85 &ndash; 70</p>
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               <p class="para_td">cyan</p>
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               <p class="para_td">70 &ndash; 50</p>
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               <p class="para_td">green</p>
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               <p class="para_td">50 &ndash; 30</p>
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               <p class="para_td">yellow</p>
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               <p class="para_td">30 &ndash; 15</p>
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               <p class="para_td">orange</p>
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               <p class="para_td">15 &ndash; 0 or error conditions</p>
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               <p class="para_td">red</p>
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      </table><br><p class="para_topic">In Fabric Flattener, this display is, by default a temporary display.&nbsp;You have the options of turning this display off or of creating NX entities. With this latter option, the entities are grouped and the entities representing each node point are named with a name of the form: {a, b} &lt; angle &ndash; off where {a, b} is the index of the point in the mesh, the angle is in degrees, and &ndash; off, if present, indicates that this point is extrapolated off of the ply edge or surface. To assess deviation of the mesh, you may view these node names by running the cursor over the objects in <b class="uiTerm">Information&rarr;Object</b>.
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      <div class="title_division">Starting point</div>
      <p class="para_division">The starting point is a point on the ply surface from which the meshing of the ply starts. &nbsp;It does not necessarily correspond to the first point of a ply that touches during actual composite layout. It is generally preferable to place the starting point to produce the best flat pattern with the least distortion. When the mesh creates, there is zero distortion at the starting point and in rows of nodes emanating in the positive and negative primary and secondary directions from the starting point. Since distortion accumulates as the meshing gets farther from the starting point, it is generally preferable to place the starting point near the center of the ply so that distortion distributes around the periphery, rather than building up from one end of the part to the other.</p>
      <div class="title_division">Fiber orientation</div>
      <p class="para_division">With the woven solver primary and secondary orientations represent directions of fibers of the fabric. With the unidirectional solver the secondary direction represents imaginary lines across the fabric surface. The secondary orientation defaults to normal to the primary direction. On the stock, these vectors represent fibers of the fabric in its original form, so for most woven material the orientations should be normal. On the ply, there may be cases where non&ndash;orthogonal orientations at the starting point, gives better results. You can only discover this by experimentation.&nbsp;Curves may also be used to specify either or both orientations. If used, the curves must lie on the ply surface and contain the start point. The mesh will attempt to follow the curves in both directions from the start point with its initial rows of nodes.</p>
      <div class="title_division">Holes and cutouts</div>
      <p class="para_division">In general holes and cutouts can cause problems with the mesh because the mesher will attempt to mesh around them. In such cases, the mesh is unlikely to be in alignment on the far side of the hole. The solver will attempt to remove those holes and cutouts that lie in a single face. Some smaller holes may mesh over without a problem, but this should not be relied on. The user should check whether any holes not removed by the fabric flattener cause problems. If so, remove them and run the fabric flattener again.</p>
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            <td valign="top" align="left"><img align="left" src="../graphics/note.gif" alt="Note" title="Note"></td>
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                  <p class="para_note_body">Removed holes can be mapped as additional curves onto the flat pattern if the user extracts the original hole edge curves before removing the hole.</p>
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