mirror of
https://git.salome-platform.org/gitpub/modules/smesh.git
synced 2024-11-12 08:39:16 +05:00
223 lines
8.0 KiB
Plaintext
223 lines
8.0 KiB
Plaintext
/*!
|
||
|
||
\page blsurf_hypo_page BLSURF Parameters hypothesis
|
||
|
||
\n BLSURF Parameters hypothesis works only with <b>BLSURF</b> 2d
|
||
algorithm. This algorithm is a commercial software.
|
||
|
||
\image html blsurf_parameters.png
|
||
|
||
<ul>
|
||
<li><b>Name</b> - allows defining the name of the hypothesis (BLSURF
|
||
Parameters_n by default).</li>
|
||
|
||
<li><b>Physical Mesh</b> - if set to "Custom", allows user input in te
|
||
in <b>User size</b>, <b>Max Physical Size</b> and <b>Min Physical
|
||
Size</b> fields.
|
||
</li>
|
||
|
||
<li><b>User size</b> - defines the size of the generated mesh elements. </li>
|
||
|
||
<li><b>Max Physical Size</b> - defines the upper limit of mesh element size. </li>
|
||
|
||
<li><b>Min Physical Size</b> - defines the lower limit of mesh element size. </li>
|
||
|
||
<li><b>Geometrical mesh</b> - if set to "Custom", allows user input in
|
||
<b>Angle Mesh S</b>, <b>Angle Mesh C</b> and
|
||
<b>Gradation</b> fields. These fields control
|
||
computation of the element size, so called <i>geometrical size</i>, conform to
|
||
the surface geometry considering local curvatures. \n
|
||
If both the <b>User size</b> and the <i>geometrical size</i> are defined, the
|
||
eventual element size correspond to the least of the two. </li>
|
||
|
||
<li><b>Angle Mesh S</b> - maximum angle between the mesh face and the
|
||
tangent to the geometrical surface at each mesh node, in degrees. </li>
|
||
|
||
<li><b>Angle Mesh C</b> - maximum angle between the mesh edge and the
|
||
tangent to the geometrical curve at each mesh node, in degrees. </li>
|
||
|
||
<li><b>Max Geometrical Size</b> - defines the upper limit of the <i>geometrical size</i>.</li>
|
||
|
||
<li><b>Min Geometrical Size</b> - defines the lower limit of the <i>geometrical size</i>.</li>
|
||
|
||
<li><b>Gradation</b> - maximum ratio between the lengths of
|
||
two adjacent edges. </li>
|
||
|
||
<li><b>Allow Quadrangles</b> - if checked, allows the creation of quadrilateral elements.</li>
|
||
|
||
<li><b>Patch independent</b> - if checked, geometrical
|
||
edges are not respected and all geometrical faces are meshed as one
|
||
hyper-face.</li>
|
||
|
||
\image html blsurf_parameters_advanced.png
|
||
|
||
<li><b>Topology</b> - allows creation of a conform mesh on a shell of
|
||
not sewed faces.
|
||
<ul>
|
||
<li>"From CAD" means that mesh conformity is assured by conformity
|
||
of a shape.</li>
|
||
<li>"Pre-process" and "Pre-process++" allow the BLSURF software to
|
||
pre-process the geometrical model to eventually produce a conform
|
||
mesh. </li>
|
||
</ul>
|
||
|
||
<li><b>Verbosity level</b> - Defines the percentage of "verbosity" of
|
||
BLSURF [0-100].</li>
|
||
|
||
<li><b>Add option</b> - provides the choice of multiple advanced
|
||
options, which appear, if selected, in a table where it is possible to
|
||
input the value of the option and to edit it later.</li>
|
||
|
||
<li><b>Clear option</b> - removes the option selected in the table.
|
||
|
||
</ul>
|
||
|
||
\n
|
||
The following options are commonly usable. The notion of <i>diag</i>
|
||
used in the descriptions means
|
||
the diagonal of the bounding box of the geometrical object to mesh.
|
||
|
||
<ul>
|
||
<li><b>topo_eps1</b> (real) - is the tolerance level inside a CAD
|
||
patch. By default is equal to <i>diag</i> <20> 10-4. This tolerance is used to
|
||
identify nodes to merge within one geometrical face when \b Topology
|
||
option is to pre-process. Default is <i>diag</i>/10.0.</li>
|
||
|
||
<li><b>topo_eps2</b> (real) - is the tolerance level between two CAD
|
||
patches. By default is equal to <i>diag</i> <20> 10-4. This tolerance is used to
|
||
identify nodes to merge over different geometrical faces when
|
||
\b Topology option is to pre-process. Default is <i>diag</i>/10.0.</li>
|
||
|
||
<li>\b LSS (real) - is an abbreviation for "length of sub-segment". It is
|
||
a maximal allowed length of a mesh edge. Default is 0.5.</li>
|
||
|
||
<li>\b frontal (integer)
|
||
<ul>
|
||
<li> 1 - the mesh generator inserts points with an advancing front method.</li>
|
||
<li> 0 - it inserts them with an algebraic method (on internal edges). This method is
|
||
slightly faster but generates less regular meshes. </li>
|
||
</ul>
|
||
Default is 0.</li>
|
||
|
||
<li>\b hinterpol_flag (integer) - determines the computation of an
|
||
interpolated value <i>v</i> between two points <i>P1</i> and <i>P2</i> on a
|
||
curve. Let <i>h1</i> be the value at point <i>P1,</i> <i>h2</i> be the value at point
|
||
<i>P2,</i> and <i>t</i> be a parameter varying from 0 to 1 when moving from <i>P1
|
||
to</i> <i>P2</i> .
|
||
<ul>
|
||
<li>0 - the interpolation is linear: <i>v = h1 + t (h2 - h1 )</i></li>
|
||
<li>1 - the interpolation is geometric: <i>v = h1 * pow( h2/h1, t)</i></li>
|
||
<li>2 - the interpolation is sinusoidal: <i>v = (h1+h2)/2 +
|
||
(h1-h2)/2*cos(PI*t)</i></li>
|
||
</ul>
|
||
Default is 0.</li>
|
||
|
||
<li>\b hmean_flag (integer) - determines the computation of the average of several
|
||
values:<ul>
|
||
<li>-1 - the minimum is computed.</li>
|
||
<li>0 or 2 - the arithmetic average computed.
|
||
<li>1 - the geometric average is computed.</li>
|
||
</ul>
|
||
Default is 0.</li>
|
||
|
||
<li>\b CheckAdjacentEdges, \b CheckCloseEdges and \b CheckWellDefined
|
||
(integers) - gives the number of calls of equally named subroutines the
|
||
purpose of which is to improve the mesh of domains having narrow
|
||
parts. At each iteration,\b CheckCloseEdges decreases the sizes of the
|
||
edges when two boundary curves are neighboring,\b CheckAdjacentEdges
|
||
balances the sizes of adjacent edges, and \b CheckWellDefined checks if
|
||
the parametric domain is well defined. Default values are 0.</li>
|
||
|
||
|
||
<li>\b CoefRectangle (real)- defines the relative thickness of the rectangles
|
||
used by subroutine \b CheckCloseEdges (see above). Default is 0.25.</li>
|
||
|
||
<li>\b eps_collapse (real) - if more than 0.0, BLSURF removes
|
||
curves whose lengths are less than \b eps_collapse. To obtain an
|
||
approximate value of the length of a curve, it is arbitrarily
|
||
split into 20 edges. Default is 0.0.</li>
|
||
|
||
<li>\b eps_ends (real) - is used to detect the curves whose lengths are very
|
||
small, which sometimes constitutes an error. A message is printed
|
||
if<i> fabs(P2-P1) < eps_ends</i>, where <i>P1</i> and <i>P2</i> are the
|
||
extremities of a curve. Default is <i>diag</i>/500.0.</li>
|
||
|
||
<li>\b prefix (char) - is a prefix of the files generated by
|
||
BLSURF. Default is "x".</li>
|
||
|
||
<li>\b refs (integer) - reference of a surface, used when exporting
|
||
files. Default is 1.</li>
|
||
</ul>
|
||
|
||
\n
|
||
The following advanced options are not documented and you can use them
|
||
at your own risk.
|
||
\n\n Interger variables:
|
||
<ul>
|
||
<li> addsurf_ivertex</li>
|
||
<li> background </li>
|
||
<li> coiter </li>
|
||
<li> communication </li>
|
||
<li> decim </li>
|
||
<li> export_flag </li>
|
||
<li> file_h </li>
|
||
<li> gridnu </li>
|
||
<li> gridnv </li>
|
||
<li> intermedfile </li>
|
||
<li> memory </li>
|
||
<li> normals </li>
|
||
<li> optim </li>
|
||
<li> pardom_flag </li>
|
||
<li> pinch </li>
|
||
<li> rigid </li>
|
||
<li> surforient </li>
|
||
<li> tconf </li>
|
||
<li> topo_collapse </li>
|
||
</ul>
|
||
Real variables:
|
||
<ul>
|
||
<li> addsurf_angle </li>
|
||
<li> addsurf_R </li>
|
||
<li> addsurf_H </li>
|
||
<li> addsurf_FG </li>
|
||
<li> addsurf_r </li>
|
||
<li> addsurf_PA </li>
|
||
<li> angle_compcurv </li>
|
||
<li> angle_ridge </li>
|
||
<li> eps_pardom </li>
|
||
</ul>
|
||
String variables:
|
||
<ul>
|
||
<li> export_format </li>
|
||
<li> export_option </li>
|
||
<li> import_option </li>
|
||
</ul>
|
||
|
||
|
||
\n
|
||
Currently BLSURF plugin has the following limitations.
|
||
<ul>
|
||
<li>The created mesh will contain inverted elements if it is based on a shape,
|
||
consisting of more than one face (box, cone, torus...) and if
|
||
the option "Allow Quadrangles (Test)" has been checked before
|
||
computation.</li>
|
||
|
||
<li>SIGFPE exception is raised at the attempt to compute the mesh
|
||
based on a box when the option "Patch independent" is checked.</li>
|
||
|
||
<li>BLSURF algorithm cannot be used as a local algorithm (on
|
||
sub-meshes) or as a provider of a low-level
|
||
mesh for some 3D algorithms, because the BLSURF mesher (and
|
||
consequently plugin) does not provide the information on node
|
||
parameters on edges (U) and faces (U,V). For example the
|
||
following combinations of algorithms are impossible:
|
||
<ul>
|
||
<li> global MEFISTO or Quadrangle(mapping) + local BLSURF;</li>
|
||
<li> BLSUFR + Projection 2D from faces meshed by BLSURF;</li>
|
||
<li> local BLSURF + Extrusion 3D;</li>
|
||
</ul>
|
||
</li>
|
||
</ul>
|
||
|
||
*/
|