\page about_meshes_page About meshes
\n \b MESH represents a discretization of a geometrical CAD model into
-a set of entities with a simple topology. In MESH there are two
-options of creation of meshes, you can:
+a set of entities with a simple topology.
-<ul>
-<li>generate meshes on the basis of geometrical shapes produced in the GEOM module,</li>
-<li>create your own meshes using the MESH functions destined for modification of generated meshes.</li>
-</ul>
+It is possible to \subpage constructing_meshes_page "construct meshes"
+on the basis of geometrical shapes produced in the GEOM module.
+Construction of \subpage constructing_submeshes_page "sub-meshes"
+allows to mesh parts of the geometrical object, for example a face,
+with different meshing parameters or using another meshing algorithm
+than other parts.
+
+3D mesh can be generated basing on a 2D closed mesh.
+
+Several created meshes can be \subpage building_compounds_page "combined into another mesh".
+
+The whole mesh or its part can be \subpage copy_mesh_page "copied" into another mesh.
+
+Meshing parameters of meshes and sub-meshes can be
+\subpage editing_meshes_page "edited", then only the mesh part
+depending on the changed parameters will be re-computed.
-The topology of a mesh is described by the relationships between its
+Meshes can be edited using the MESH functions destined for
+\ref modifying_meshes_page "modification" of generated meshes.
+
+Meshes are stored in DAT, MED, UNV, STL, CGNS, GMF and SAUVE formats and can be
+\subpage importing_exporting_meshes_page "imported from and exported to"
+ the file in these formats.
+
+The \b topology of a mesh is described by the relationships between its
entities including:
<ul>
<li>\b Node — 0D object of a mesh presented by a point with coordinates (x, y, z).</li>
+<li>\b 0D element — element of a mesh defined by one node.</li>
<li>\b Edge — 1D element of a mesh defined by two nodes.</li>
<li>\b Face — 2D element of a mesh defined by three or four edges (closed contour).</li>
<li>\b Volume — 3D element of a mesh defined by several faces.</li>
+<li>\b Ball element — discrete element of a mesh defined by a node and a diameter.</li>
</ul>
These entities are
considered as topological entities and they don't
imply any geometric representation. Only \b Nodes reference geometric
representations of points with definite coordinates. The node entity
-will contain additional information about its position in the space
+contains additional information about its position in the space
and its relations with the meshed CAD model. Its position could be
described in the following way:
<ul>
-<li><b>2D position</b>. It is a free position defined by only two coordinates x,y.</li>
-<li><b>3D position</b>. It is a free position defined by three coordinates x,y and z. </li>
+<li><b>3D position</b>. It characterizes the position of a node in a
+ solid geometry and is defined by three coordinates x,y and z and a
+ reference to the solid geometrical entity. </li>
<li><b>Surface position</b>. It characterizes the position of a node on a
-geometric surface and is defined by the u,v position in the parametric
-space of the corresponding surface.</li>
+ geometric surface and is defined by the u,v position in the parametric
+ space of the corresponding surface.</li>
<li><b>Line position</b>. It characterizes the position of a node on a
-geometric curve and is defined by the u parameter and the
-corresponding curve.</li>
+ geometric curve and is defined by the u parameter and the
+ corresponding curve.</li>
<li><b>Vertex position</b>. It characterizes the position of a node on a
-geometric point of the meshed CAD model and is defined by the x,y,z
-coordinates of the corresponding vertex.</li>
+ geometric point of the meshed CAD model and is defined by the x,y,z
+ coordinates of the corresponding vertex.</li>
</ul>
-<br><h2>Connections</h2>
-
-Each mesh entity bounds 0 or more mesh entities of higher
-dimension. In the same way each mesh entity is bounded by 0 or more
-mesh entities of lower dimension:
-
-<ul>
-<li>A node bounds edges, faces and volumes</li>
-<li>An edge bounds faces, and volumes</li>
-<li>A face bounds volumes</li>
-<li>A volume is bounded by faces, edges and nodes</li>
-<li>A face is bounded by edges, and nodes</li>
-<li>An edge is bounded by nodes</li>
-</ul>
-
-You can notice that there are two types of connections: \b inverse and
-\b direct connections.
-
-<br><h2>Inverse connections</h2>
-
-This relationship has a particularity that the order of bounded
-entities has not a direct meaning. Also the number of bounded entities
-is not fixed.
-
-\b Example: The edges surrounding a node. The 3rd edge has no more
-sense that the 5th one.
-
-<br><h2>Direct connections</h2>
-
-This relationship has a particularity that the order of bounding
-entities is meaningful. The number of bounding entities is fixed and
-depends on the type of the entity (hexahedron, tetrahedron,?).
-
-\b Example: An edge is composed of two nodes. A face is composed of 3
-or 4 edges depending if we are dealing with triangles or quadrangles.
-
-The connections are not only restricted to entities of one dimension
-higher or lower. For example some algorithms may be interested to
-retrieve all the faces surrounding a node.
-
*/
