cogenoctree.html

Delaunay三角形的网格剖分程序

<TITLE>COG 2.1: Octree</TITLE>

<H1>CogenOctree</H1>

 <P>The class <B>CogenOctree</B> is defined in 
 <A HREF="cogenoctree.hxx">cogenoctree.hxx</A>. 
 Examples of application of this class can be found:

 <UL>
 <LI> <A HREF="mainstarttest.html">simplest 3D standard cube</A>
 <LI> <A HREF="mainoctreetest.html">definition of regions</A>
 <LI> <A HREF="mainfacetest.html">definition of faces</A>
 <LI> <A HREF="maincogtest.html">frame for other geometries</A>
 <LI> see also the <A HREF="tutorial.html">tutorial</A> for other examples.
 </UL>

 <P>The octree algorithm consists of several steps:

 <H3>Coarse Octree</H3>

 <P>As the starting octree, we use a regular grid which contains the
corners of all boxes defined for this octree.
 
 <H3>Refinement</H3>

 <P>The coarse grid is refined using the refinement metric.

 <H3>Boundary Computation</H3>

 <P>Boundary face nodes are computed as intersection of octree
edges with boundary faces. 
 <P>Then, boundary edges are computed as intersection of octree
faces with boundary edges.
 <P>Last, boundary vertices in octree cells are computed.

 <H3><A HREF="noderemoval.html">Node Removal</A></H3>

 <P>In this part, some of the nodes created in the previous steps
which for various reasons are considered bad are removed. 

 <H3>Delaunay Grid Generation</H3>

 <P>Then, for all remaining nodes a Delaunay grid generation algorithm
is used to create the resulting grid.

<H2>Warnings</H2>

<H3><A NAME="empty region">empty region</A></H3>

 <P>You try define a region with empty volume. Check your input data.

<H3><A NAME="empty face">empty face</A></H3>

 <P>You try define a face with empty area. Check your input data.