smesh/doc/salome/gui/SMESH/files/sewing_meshes.htm
2004-12-01 10:48:31 +00:00

329 lines
11 KiB
HTML
Executable File

<!doctype HTML public "-//W3C//DTD HTML 4.0 Frameset//EN">
<html>
<!--(==============================================================)-->
<!--(Document created with RoboEditor. )============================-->
<!--(==============================================================)-->
<head>
<title>Sewing meshes</title>
<!--(Meta)==========================================================-->
<meta http-equiv=content-type content="text/html; charset=windows-1252">
<meta name=generator content="RoboHELP by eHelp Corporation - www.ehelp.com">
<meta name=generator-major-version content=0.1>
<meta name=generator-minor-version content=1>
<meta name=filetype content=kadov>
<meta name=filetype-version content=1>
<meta name=page-count content=1>
<meta name=layout-height content=3595>
<meta name=layout-width content=740>
<!--(Links)=========================================================-->
<link rel='stylesheet' href='../default_ns.css'>
<script type="text/javascript" language="JavaScript" title="WebHelpSplitCss">
<!--
if (navigator.appName !="Netscape")
{ document.write("<link rel='stylesheet' href='../default.css'>");}
//-->
</script>
<style type="text/css">
<!--
img_whs1 {border-style: none; border: none; width: 30px; height: 30px; float: none;}
ul.whs2 {list-style: disc;}
p.whs3 {font-weight: bold;}
p.whs4 {margin-left: 40px;}
img_whs5 {border-style: none; border: none; width: 311px; height: 456px;}
img_whs6 {border-style: none; border: none; width: 297px; height: 62px;}
img_whs7 {border-style: none; border: none; width: 612px; height: 225px;}
img_whs8 {border-style: none; border: none; width: 612px; height: 230px;}
img_whs9 {border-style: none; border: none; width: 600px; height: 227px;}
img_whs10 {border-style: none; border: none; width: 620px; height: 228px;}
img_whs11 {border-style: none; border: none; width: 304px; height: 222px;}
-->
</style>
<script type="text/javascript" language="JavaScript" title="WebHelpInlineScript">
<!--
function reDo() {
if (innerWidth != origWidth || innerHeight != origHeight)
location.reload();
}
if ((parseInt(navigator.appVersion) == 4) && (navigator.appName == "Netscape")) {
origWidth = innerWidth;
origHeight = innerHeight;
onresize = reDo;
}
onerror = null;
//-->
</script>
<style type="text/css">
<!--
div.WebHelpPopupMenu {position:absolute; left:0px; top:0px; z-index:4; visibility:hidden;}
-->
</style>
<script type="text/javascript" language="javascript1.2" src="../whmsg.js"></script>
<script type="text/javascript" language="javascript" src="../whver.js"></script>
<script type="text/javascript" language="javascript1.2" src="../whproxy.js"></script>
<script type="text/javascript" language="javascript1.2" src="../whutils.js"></script>
<script type="text/javascript" language="javascript1.2" src="../whtopic.js"></script>
</head>
<!--(Body)==========================================================-->
<body>
<script type="text/javascript" language="javascript1.2">
<!--
if (window.gbWhTopic)
{
if (window.addTocInfo)
{
addTocInfo("SMESH module\nModifying meshes\nTransforming meshes\nSewing meshes");
addButton("show",BTN_TEXT,"Show","","","","",0,0,"","","");
}
if (window.writeBtnStyle)
writeBtnStyle();
if (window.writeIntopicBar)
writeIntopicBar(1);
if (window.setRelStartPage)
{
setRelStartPage("../smesh.htm");
autoSync(0);
sendSyncInfo();
sendAveInfoOut();
}
}
else
document.location.reload();
//-->
</script>
<h1>Sewing meshes</h1>
<p><img src="../i_blue.jpg" x-maintain-ratio="TRUE" width="30px" height="30px" border="0" class="img_whs1"> In SMESH you can sew elements of &nbsp;different
meshes. The current functionality allows you to sew:</p>
<p>&nbsp;</p>
<ul type="disc" class="whs2">
<li class=kadov-p><p class="whs3"><a href="#free bord">Free
borders </a></p></li>
<li class=kadov-p><p class="whs3"><a href="#conform">Conform
free borders</a></p></li>
<li class=kadov-p><p class="whs3"><a href="#border to side">Border
to side</a></p></li>
<li class=kadov-p><p class="whs3"><a href="#side elements">Side
elements</a></p></li>
</ul>
<p class="whs3">&nbsp;</p>
<p class=TODO>To sew elements of different meshes:</p>
<p class=TODO>&nbsp;</p>
<p class="whs4">1. From the <span style="font-weight: bold;"><B>Modification
</B></span>menu choose the <span style="font-weight: bold;"><B>Transformation
</B></span>item and &nbsp;from
its sub-menu select the <span style="font-weight: bold;"><B>Sewing </B></span>item.
The following dialog box shall appear:</p>
<p class="whs4">&nbsp;</p>
<p class="whs4"><img src="../image57.gif" width="311px" height="456px" border="0" class="img_whs5"></p>
<p class="whs4">&nbsp;</p>
<p class="whs4">2. In the upper part of this dialog box check
one of the radio buttons corresponding to the type of sewing operation
you would like to perform: </p>
<p class="whs4">&nbsp;</p>
<p class="whs4"><img src="../image61.gif" width="297px" height="62px" border="0" class="img_whs6"> </p>
<p class="whs4">&nbsp;</p>
<p class="whs4">3. Fill the other fields available in the
dialog box</p>
<p class="whs4">4. Click the <span style="font-weight: bold;"><B>OK
</B></span><span>or </span><span style="font-weight: bold;"><B>Apply </B></span>button
to perform the operation of sewing. </p>
<p class="whs3">&nbsp;</p>
<h3><a name="free bord"></a>Sew free borders</h3>
<p>This functionality allows you to unite two free borders of a 2D mesh.</p>
<p>&nbsp;</p>
<p>For sewing free borders you should define three points on each border:
first, second and the last node: </p>
<p>&nbsp;</p>
<ul type="disc" class="whs2">
<li class=kadov-p><p>&nbsp;the
first node specifies beginning of the border ;</p></li>
<li class=kadov-p><p>&nbsp;the
second node specifies the part of the border which should be considered
(as far as the free border usually forms a closed contour);</p></li>
<li class=kadov-p><p>&nbsp;the
last node specifies the end of the border.</p></li>
</ul>
<p>&nbsp;</p>
<p>You can select these nodes in the 3D viewer or define by its id.</p>
<p>&nbsp;</p>
<p>The first and the second nodes should belong to the same link of a face.
The second and the last nodes of a border can be the same. The first and
the last nodes of two borders can be the same. The corresponding end nodes
of two borders will be merged. Intermediate nodes of two borders will
be either merged or inserted into faces of the opposite border.</p>
<p>&nbsp;</p>
<p>The sewing algorithm is as follows:</p>
<p>&nbsp;</p>
<p class="whs4">1. The parameter (U) of each node within
a border is computed. So that the first node has U=0.0, the last node
has U=1.0, for the rest nodes 0.0 &lt; U &lt; 1.0;</p>
<p class="whs4">2. Compare node parameters of the two borders.
If two nodes of the opposite borders have close parameters, they are merged,
i.e. a node of the first border is replaced in all elements by a node
of the second border. If a node has no node with a close parameter in
the opposite border, it is inserted into an edge of element of the opposite
border, an element is split. Two nodes are considered close enough to
merge, if difference of their parameters is less than one fifth of minimum
length of adjacent face edges on the borders.</p>
<p>&nbsp;</p>
<p class="whs4"><img src="../image22.jpg" width="612px" height="225px" border="0" class="img_whs7"></p>
<p class="whs4">&nbsp;</p>
<h3><a name=conform></a>Sew conform free borders</h3>
<p>This functionality can be used to unite two free borders of a 2D mesh.</p>
<p>&nbsp;</p>
<p>The borders of meshes for sewing are defined as for &quot;Sew free borders&quot;
except that the second free border is not limited and can be defined by
the first and the second nodes only. The first nodes of two borders can
be the same.</p>
<p>&nbsp;</p>
<p class="whs4"><img src="../image23.jpg" width="612px" height="230px" border="0" class="img_whs8"></p>
<p>The algorithm is following: counting nodes starting at the first ones,
the n-th node of the first border is merged with the n-th node of the
other border, until the end of either of borders. Nodes of the first border
are replaced in all elements with corresponding nodes of the second border.</p>
<p>For sewing conform free borders you should define three points on the
first border and two points on the second one. User can select these nodes
in 3D viewer or define node by its id.</p>
<p class="whs3">&nbsp;</p>
<p class="whs3">&nbsp;</p>
<h3><a name="border to side"></a>Sew border to side</h3>
<p>&quot;Sew border to side&quot; is intended to sew a free border to a
mesh surface.</p>
<p>The free border is defined as for &quot;Sewing of free borders&quot;.
The place where to sew the border is defined by two nodes, between which
the border faces are placed, so that the first border node is merged with
the first node on the side and the last node of the border is merged with
the second specified node on the side.</p>
<p>&nbsp;</p>
<p class="whs4"><img src="../image30.jpg" width="600px" height="227px" border="0" class="img_whs9"></p>
<p>The algorithm is following.</p>
<p>1. Find a sequence of linked nodes on the side such that the found links
to be most co-directed with the links of the free border.</p>
<p>2. Sew two sequences of nodes using algorithm of &quot;Sewing of free
berders&quot;.</p>
<p>For sewing border to side you should define three points on the border
and two points on the side. User can select these nodes in 3D viewer or
define node by its id.</p>
<p>&nbsp;</p>
<h3><a name="side elements"></a>Sew side elements</h3>
<p class="whs4">&nbsp;</p>
<p>&nbsp;</p>
<p class="whs4"><img src="../image31.jpg" width="620px" height="228px" border="0" class="img_whs10"></p>
<p>This operation is intended to unite two mesh surfaces.</p>
<p>Surfaces may be defined by either 2d or 3d elements. The number of given
elements of the sides must be the same. The sets of given elements must
be topologically equal, i.e. each node of one element set must have a
corresponding node in the other element set and corresponding nodes must
be equally linked. If there are 3d elements in a set, only their free
faces must obey to that rule.</p>
<p>Two corresponding nodes on each side must be specified. They must belong
to one element and must be located on an element set boundary.</p>
<p>Sewing algorithm finds and merges the corresponding nodes starting from
the specified ones.</p>
<p>&nbsp;</p>
<p class="whs4"><img src="../image32.jpg" width="304px" height="222px" border="0" class="img_whs11"></p>
<p>For sewing side elements you should define elements for sewing and two
nodes for merging on the each side. User can select these elements and
nodes in 3D viewer or define them by its id.</p>
<p>&nbsp;</p>
<script type="text/javascript" language="javascript1.2">
<!--
if (window.writeIntopicBar)
writeIntopicBar(0);
//-->
</script>
</body>
</html>