About "Use Existing Faces" stub algorithm

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eap 2012-07-19 12:44:41 +00:00
parent 562103aee9
commit 4fd207ba70
4 changed files with 364 additions and 176 deletions

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@ -62,6 +62,9 @@ There is also a number of more specific algorithms:
<li>\subpage prism_3d_algo_page "for meshing prismatic shapes"</li>
<li>\subpage radial_quadrangle_1D2D_algo_page "for meshing special 2d faces (circles and part of circles)"</li>
</ul>
\ref use_existing_anchor "Use existing edges" and
\ref use_existing_anchor "Use existing faces" algorithms can be
used to create an 1D or a 2D mesh in a python script.
\ref constructing_meshes_page "Constructing meshes" page describes in
detail how to apply meshing algorithms.

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@ -2,106 +2,142 @@
\page constructing_meshes_page Constructing meshes
\n Construction of a mesh consists of:
\n Construction of a mesh on some geometry consists of:
<ul>
<li>Selecting a geometrical object for meshing</li>
<li>Applying \subpage basic_meshing_algos_page "meshing algorithms" and
\subpage about_hypo_page "hypotheses" which will be used at computation of
this mesh.</li>
<li> \ref create_mesh_anchor "Creating of a mesh object"</li>
<li> \ref evaluate_anchor "Evaluating mesh size"</li>
<li> \ref preview_anchor "Previewing the mesh"</li>
<li> \ref submesh_order_anchor "Changing submesh priority"</li>
<li> \ref compute_anchor "Computing the mesh"</li>
</ul>
Mesh can be \ref use_existing_anchor "computed using your own meshing algorithms"
written in Python.
\anchor create_mesh_anchor
<h2>Creation of a mesh object</h2>
<em>To construct a mesh:</em>
<ol>
<li>In the \b Mesh menu select <b>Create Mesh</b> or click <em>"Create
Mesh"</em> button in the toolbar.
<li>Select a geometrical object for meshing.</li>
<li>In the \b Mesh menu select <b>Create Mesh</b> or click <em>"Create
Mesh"</em> button in the toolbar.
\image html image32.png
<center><em>"Create Mesh" button</em></center>
\image html image32.png
<em>"Create Mesh" button</em>
The following dialog box will appear:
The following dialog box will appear:
\image html createmesh-inv.png
</li>
<li>For example, you need to mesh a 3d object.
\n First, type the name for your mesh in the "Name" box, by default,
it is "Mesh_1". Then select the object you wish to mesh in the Object
Browser and click the "Add" button (if name of the object not yet
appeared in \b Geometry field).
\image html createmesh-inv.png
<br>
</li>
<li>Apply \subpage basic_meshing_algos_page "meshing algorithms" and
\subpage about_hypo_page "hypotheses" which will be used at computation of
this mesh.
\image html image120.png
<center><em>"Add" button</em></center>
For example, you need to mesh a 3D object.
Now you can define 1d Algorithm and 1d Hypotheses, which will be
applied to the edges of your object. (Note that any object has edges,
even if their existence is not apparent, for example, a sphere has 4
edges). Click the <em>"Add Hypothesis"</em> button to add a
hypothesis.
First, type the name for your mesh in the \b Name box, by default,
it is "Mesh_1". Then select the geometrical object you wish to
mesh in the Object Browser and click "Select" button near \b Geometry
field (if name of the object not yet appeared in \b Geometry field).
\image html image121.png
<center><em>"Add Hypothesis" button</em></center>
\image html image120.png
<em>"Select" button</em>
Click the <em>"Edit Hypothesis"</em> button to define values for the
current hypothesis.
Now you can define 3D Algorithm and 3D Hypotheses, which will be
applied to solids of your geometrical object. Click the <em>"Add
Hypothesis"</em> button to add a hypothesis.
\image html image122.png
<center><em>"Edit Hypothesis" button</em></center>
\image html image121.png
<em>"Add Hypothesis" button</em>
The use of additional hypotheses is optional (i.e. you may leave
"None" in this box).
Click the <em>"Edit Hypothesis"</em> button to change values for the
current hypothesis.
Proceed in the same way with 2d and 3d Algorithms and Hypotheses, note
that the choice of hypotheses depends on the algorithm. There must be
one Algorithm and zero or several Hypotheses for each dimension of your
object (most standard 2D and 3D algorithms can work without
hypotheses using some default parameters),
otherwise you will not get any mesh at all. Of course, if you
wish to mesh a face, which is a 2d object, you don't need to define 3d
Algorithm and Hypotheses.
\n In the <b>Object Browser</b> the structure of the new mesh will be
displayed as follows:
\image html image122.png
<em>"Edit Hypothesis" button</em>
\image html image88.jpg
Most standard 2D and 3D algorithms can work without hypotheses
using some default parameters. The use of additional hypotheses
is optional (i.e. you may leave "None" in this box).
It contains:
<ul>
<li>a reference to the geometrical object on the basis of which the mesh has been constructed;</li>
<li><b>Applied hypotheses</b> folder containing the references to the
hypotheses applied to the construction of the mesh;</li>
<li><b>Applied algorithms</b> folder containing the references to the
algorithms applied to the construction of the mesh.</li>
</ul>
<br>
There is an alternative way to create a mesh on an object simply by
clicking <b>Assign a set of hypotheses</b> button and selecting among
pre-defined sets of hypotheses. In addition to the standard
sets of hypotheses, it is possible to create custom sets by editing
CustomMeshers.xml file located in the home directory. CustomMeshers.xml
file must describe sets of hypotheses in the
same way as ${SMESH_ROOT_DIR}/share/salome/resources/smesh/StdMeshers.xml
file does (sets of hypotheses are enclosed between <hypotheses-set-group>
tags).
\image html hypo_sets.png
<center>List of sets of hypotheses: <em>[custom]</em> is automatically added to the sets defined
by the user</center>
</li>
Proceed in the same way with 2D and 1D Algorithms and Hypotheses that
will be used to mesh faces and edges of your geometry. (Note
that any object has edges, even if their existence is not
apparent, for example, a sphere has 4 edges). Note that the
choice of hypotheses and of an algorithm of lower dimension depends on
the algorithm.
\anchor preview_mesh_anchor
Some algorithms generate mesh of several dimensions while others, of
only one dimension. In the latter case there must be one Algorithm and zero or several
Hypotheses for each dimension of your object, otherwise you will
not get any mesh at all. Of course, if you wish to mesh a face,
which is a 2D object, you don't need to define 3D Algorithm and
Hypotheses.
<li> After the mesh object is created and all hypotheses are assigned and
before the mesh computation, it is possible to see the mesh preview.
In the <b>Object Browser</b> the structure of the new mesh will be
displayed as follows:
\image html image88.jpg
It contains:
<ul>
<li>a reference to the geometrical object on the basis of
which the mesh has been constructed;</li>
<li><b>Applied hypotheses</b> folder containing the references
to the hypotheses applied at the construction of the mesh;</li>
<li><b>Applied algorithms</b> folder containing the references
to the algorithms applied at the construction of the mesh.</li>
</ul>
There is an alternative way to assign Algorithms and Hypotheses by
clicking <b>Assign a set of hypotheses</b> button and selecting among
pre-defined sets of hypotheses. In addition to the standard
sets of hypotheses, it is possible to create custom sets by editing
CustomMeshers.xml file located in the home directory. CustomMeshers.xml
file must describe sets of hypotheses in the
same way as ${SMESH_ROOT_DIR}/share/salome/resources/smesh/StdMeshers.xml
file does (sets of hypotheses are enclosed between <hypotheses-set-group>
tags).
\image html hypo_sets.png
List of sets of hypotheses: <em>[custom]</em>
automatically added to the sets defined by the user
</li>
</ol>
Consider trying a sample script for construction of a mesh from our
\ref tui_creating_meshes_page "TUI Scripts" section.
\anchor evaluate_anchor
<h2>Evaluating mesh size</h2>
After the mesh object is created and all hypotheses are assigned and
before \ref compute_anchor "Compute" operation, it is possible to
calculate the eventual mesh size. For this, select the mesh in
the <b>Object Browser</b> and from the \b Mesh menu select \b
Evaluate. The result of evaluation will be displayed in the following
information box:
\image html mesh_evaluation_succeed.png
\anchor preview_anchor
<h2>Previewing the mesh</h2>
Before \ref compute_anchor "the mesh computation", it is also possible
to see the mesh preview.
For this, select the mesh in the Object Browser. From the \b Mesh menu
select \b Preview or click "Preview" button in the
toolbar or activate "Preview" item from the pop-up menu.
select \b Preview or click "Preview" button in the toolbar or activate
"Preview" item from the pop-up menu.
\image html mesh_precompute.png
<center><em>"Preview" button</em></center>
<em>"Preview" button</em>
Select <b>1D mesh</b> or <b>2D mesh</b> preview mode in the Preview dialog.
\image html preview_mesh_1D.png "1D mesh preview shows nodes computed on geometry edges"
<br>
\image html preview_mesh_2D.png "2D mesh preview shows edge mesh elements, computed on geometry faces"
<b>Compute</b> button computes the whole mesh.
@ -111,17 +147,105 @@ created mesh elements appers:
\image html preview_tmp_data.png
These elenents can be reused in the next mesh computation.
</li>
These elements can be kept in the mesh.
<li>It is equally possible to skip the Preview and \b Compute the mesh
after the hypotheses are assigned. For this, select your mesh in the <b>Object
Browser</b>. From the \b Mesh menu select \b Compute or click "Compute" button of the
toolbar.
\anchor submesh_order_anchor
<h2>Changing submesh priority</h2>
If the mesh contains concurrent \ref constructing_submeshes_page "submeshes",
it is possible to change the priority of their computation, i.e. to
change the priority of applying algorithms to the shared sub-shapes of
the Mesh shape.
<em>To change submesh priority:</em>
Choose "Change submesh priority" from the Mesh menu or a pop-up
menu. The opened dialog shows a list of submeshes in the order of
their priority.
There is an example of submesh order modifications of the Mesh created on a Box
shape. The main Mesh object:
<ul>
<li><i>1D</i> <b>Wire discretisation</b> with <b>Number of Segments</b>=20</li>
<li><i>2D</i> <b>Triangle (Mefisto)</b> with Hypothesis<b>Max Element Area</b>
</li>
</ul>
The first submesh object <b>Submesh_1</b> created on <b>Face_1</b> is:
<ul>
<li><i>1D</i> <b>Wire discretisation</b> with <b>Number of Segments</b>=4</li>
<li><i>2D</i> <b>Triangle (Mefisto)</b> with Hypothesis<b>MaxElementArea</b>=1200</li>
</ul>
The second submesh object <b>Submesh_2</b> created on <b>Face_2</b> is:
<ul>
<li><i>1D</i> <b>Wire discretisation</b> with <b>Number of Segments</b>=8</li>
<li><i>2D</i> <b>Triangle (Mefisto)</b> with Hypothesis<b>MaxElementArea</b>=1200</li>
</ul>
And the last submesh object <b>Submesh_3</b> created on <b>Face_3</b> is:
<ul>
<li><i>1D</i> <b>Wire discretisation</b> with <b>Number of Segments</b>=12</li>
<li><i>2D</i> <b>Triangle (Mefisto)</b> with Hypothesis<b>MaxElementArea</b>=1200</li>
</ul>
The sub-meshes become concurrent if they share sub-shapes that can be
meshed with different algorithms (or different hypothesises). In the
example, we have three submeshes with concurrent algorithms, because
they have different hypotheses.
The first mesh computation is made with:
<center>
\image html mesh_order_123.png
<em>"Mesh order SubMesh_1, SubMesh_2, SubMesh_3"</em></center>
<center>
\image html mesh_order_123_res.png
<em>"Result mesh with order SubMesh_1, SubMesh_2, SubMesh_3 "</em></center>
The next mesh computation is made with:
<center>
\image html mesh_order_213.png
<em>"Mesh order SubMesh_2, SubMesh_1, SubMesh_3"</em></center>
<center>
\image html mesh_order_213_res.png
<em>"Result mesh with order SubMesh_2, SubMesh_1, SubMesh_3 "</em></center>
And the last mesh computation is made with:
<center>
\image html mesh_order_321.png
<em>"Mesh order SubMesh_3, SubMesh_2, SubMesh_1"</em></center>
<center>\image html mesh_order_321_res.png
<em>"Result mesh with order SubMesh_3, SubMesh_2, SubMesh_1 "</em></center>
As we can see, each mesh computation has a different number of result
elements and a different mesh discretisation on the shared edges (the edges
that are shared between <b>Face_1</b>, <b>Face_2</b> and <b>Face_3</b>)
Additionally, submesh priority (the order of applied algorithms) can
be modified not only in a separate dialog box, but also in
the <b>Preview</b>. This helps to preview different mesh results,
modifying the order of submeshes.
<center>
\image html mesh_order_preview.png
<em>"Preview with submesh priority list box"</em></center>
If there are no concurrent submeshes under the Mesh object, the user
will see the following information.
<center>
\image html mesh_order_no_concurrent.png
<em>"No concurrent submeshes detected"</em></center>
\anchor compute_anchor
<h2>Computing the mesh</h2>
It is equally possible to skip \ref evaluate_anchor "the Evaluation"
and \ref preview_anchor "the Preview" and to \b Compute the mesh after
the hypotheses are assigned. For this, select your mesh in
the <b>Object Browser</b>. From the \b Mesh menu select \b Compute or
click "Compute" button of the toolbar.
\image html image28.png
<center><em>"Compute" button</em></center>
<em>"Compute" button</em>
The Mesh Computation information box appears.
@ -133,9 +257,12 @@ failure is provided.
\image html meshcomputationfail.png
After you select the error, <b>Show Sub-shape</b> button allows
visualizing the geometrical entity that causes it.
visualizing in magenta the geometrical entity that causes it.
\image html failed_computation.png
<em>3D algorithm failed to compute mesh on a box shown using <b>Show
Sub-shape</b> button</em>
\image html failed_computation.png "Example of the invalid input mesh"
\note Mesh Computation Information box does not appear if you set
"Mesh computation/Show a computation result notification" preference
@ -149,104 +276,38 @@ failed, in GEOM component as a child of the mesh geometry, which
allows analyzing the problem geometry and creating a submesh on it in
order to locally tune hypotheses.
<b>NOTE</b> It is possible to define a 1D or a 2D mesh in a
python script and then use such submeshes in the construction of a 3D
mesh. For this, there exist two algorithms: <b>Use existing edges</b> and <b>Use
existing faces</b>. They are not entirely usable from the GUI, so a
mesh created using these algorithms should be exported into a python
script, edited and then imported into the GUi.
If a cause of failure is an invalid input mesh and the algorithm has
provided information on what mesh entities are bad <b>Show bad Mesh</b>
button appears in the dialog. Clicked, it shows bad mesh entities in
the Viewer in magenta. Sometimes the shown mesh entities are too small
or/and hidden by other mesh elements, to see them it can be helpful to
switch the mesh to Wireframe visualization mode or to switch off
visualization of faces and volumes (if any).
<li>It is possible to calculate the eventual mesh size
before \b Compute operation. For this, select the mesh in the <b>Object
Browser</b> and from the \b Mesh menu select \b Evaluate. The result of
evaluation will be displayed in the following information box:
\anchor use_existing_anchor
<h2>"Use existing edges" and "Use existing faces" algorithms</h2>
\image html mesh_evaluation_succeed.png
</li>
\anchor mesh_order_anchor
<li>
If the mesh contains concurrent submeshes, it is possible to change
the priority of their computation, i.e. to change the priority of
applying algorithms to the shared sub-shapes of the Mesh shape.</li>
<em>To change submesh priority:</em>
<li>Choose "Change submesh priority" from the Mesh menu or a popup menu. The opened dialogue
shows a list of submeshes in the order of their priority.
There is an example of submesh order modifications of the Mesh created on a Box
shape. The main Mesh object:
It is possible to create an 1D or a 2D mesh in a python script
(using <em>AddNode, AddEdge</em> and <em>AddFace</em> commands) and
then use such sub-meshes in the construction of a 2D or a 3D mesh. For
this, there exist two algorithms: <b>Use existing edges</b> and <b>Use
existing faces</b>. Scenario of their usage is following. For
example, you want to use standard algorithms to generate 1D and 3D
meshes and to create 2D mesh by your python code. Then you
<ul>
<li><i>1D</i> <b>Wire discretisation</b> with <b>Number of Segments</b>=20</li>
<li><i>2D</i> <b>Triangle (Mefisto)</b> with Hypothesis<b>Max Element Area</b>
</li>
</ul>
The first submesh object <b>Submesh_1</b> created on <b>Face_1</b>
is:
<ul>
<li><i>1D</i> <b>Wire discretisation</b> with <b>Number of Segments</b>=4</li>
<li><i>2D</i> <b>Triangle (Mefisto)</b> with Hypothesis<b>MaxElementArea</b>=1200</li>
</ul>
The second submesh object <b>Submesh_2</b> created on <b>Face_2</b>
is:
<ul>
<li><i>1D</i> <b>Wire discretisation</b> with <b>Number of Segments</b>=8</li>
<li><i>2D</i> <b>Triangle (Mefisto)</b> with Hypothesis<b>MaxElementArea</b>=1200</li>
<li> create a mesh object, assign an 1D algorithm,</li>
<li> invoke \b Compute command, which computes an 1D mesh,</li>
<li> assign <b>Use existing faces</b> and a 3D algorithm,</li>
<li> run your python code, which creates a 2D mesh,</li>
<li> invoke \b Compute command, which computes a 3D mesh.</li>
</ul>
And the last submesh object <b>Submesh_3</b> created on <b>Face_3</b>
is:
<ul>
<li><i>1D</i> <b>Wire discretisation</b> with <b>Number of Segments</b>=12</li>
<li><i>2D</i> <b>Triangle (Mefisto)</b> with Hypothesis<b>MaxElementArea</b>=1200</li>
</ul>
Consider trying a sample script demonstrating usage of
\ref tui_use_existing_faces "Use existing faces" algorithm for
construction of a 2D mesh using Python commands.
The submeshes become concurrent if they share sub-shapes that can be meshed
with different algorithms (or different hypothesises).
In the example, we have three submeshes with concurrent algorithms,
because they have different hypotheses.
The first mesh computation is made with:
\image html mesh_order_123.png
<center><em>"Mesh order SubMesh_1, SubMesh_2, SubMesh_3"</em></center>
\image html mesh_order_123_res.png
<center><em>"Result mesh with order SubMesh_1, SubMesh_2, SubMesh_3 "</em></center>
The next mesh computation is made with:
\image html mesh_order_213.png
<center><em>"Mesh order SubMesh_2, SubMesh_1, SubMesh_3"</em></center>
\image html mesh_order_213_res.png
<center><em>"Result mesh with order SubMesh_2, SubMesh_1, SubMesh_3 "</em></center>
And the last mesh computation is made with:
\image html mesh_order_321.png
<center><em>"Mesh order SubMesh_3, SubMesh_2, SubMesh_1"</em></center>
\image html mesh_order_321_res.png
<center><em>"Result mesh with order SubMesh_3, SubMesh_2, SubMesh_1 "</em></center>
As we can see, each mesh computation has a different number of result
elements and a different mesh discretisation on the shared edges (the edges
that are shared between <b>Face_1</b>, <b>Face_2</b> and <b>Face_3</b>)
Additionally, submesh priority (the order of applied algorithms) can
be modified not only in a separate dialog box, but also in the
<b>Preview</b>. This helps to preview different mesh results,
modifying the order of submeshes.
\image html mesh_order_preview.png
<center><em>"Preview with submesh priority list box"</em></center>
If there are no concurrent submeshes under the Mesh object, the user will see the
following information.
\image html mesh_order_no_concurrent.png
<center><em>"No concurrent submeshes detected"</em></center>
</ol>
Consider trying a sample script for construction of a mesh from our
\ref tui_creating_meshes_page "TUI Scripts" section.
\image html use_existing_face_sample_mesh.png
<em> Mesh computed by \ref tui_use_existing_faces "the sample script"
shown in a Shrink mode.</em>
*/

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@ -18,7 +18,7 @@ while the box is a 3D object. <br>
will be used. This means that an edge shared by two faces each having
its own different sub-mesh, will be meshed using algorithms and
hypotheses of any of the two, chosen randomly. This indeterminacy can
be fixed by defining \ref mesh_order_anchor "Sub-mesh priority".
be fixed by defining \ref submesh_order_anchor "Sub-mesh priority".
<br>
\n Construction of a sub-mesh consists of:

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@ -0,0 +1,124 @@
/*!
\page tui_use_existing_faces Use existing faces
This sample demonstrates how to use <b>Use existing faces</b> algorithm,
which is actulally just a stub allowing to use your own 2D algoritm
implemented in Python.
\code
import smesh, geompy
import numpy as np
# define my 2D algorithm
def my2DMeshing( geomFace ):
# find gravity center of geomFace
gcXYZ = geompy.PointCoordinates( geompy.MakeCDG( geomFace ))
# define order and orientation of edges
sortedEdges = []
geomEdges = geompy.SubShapeAll( geomFace, geompy.ShapeType["EDGE"])
sortedEdges.append(( geomEdges.pop(0), True ))
while geomEdges:
prevEdge_rev = sortedEdges[ -1 ]
prevVV = geompy.SubShapeAll( prevEdge_rev[0], geompy.ShapeType["VERTEX"])
prevV2 = prevVV[ prevEdge_rev[1] ]
found = False
for iE in range( len( geomEdges )):
v1,v2 = geompy.SubShapeAll( geomEdges[ iE ], geompy.ShapeType["VERTEX"])
same1,same2 = [( geompy.MinDistance( prevV2, v ) < 1e-7 ) for v in [v1,v2] ]
if not same1 and not same2: continue
sortedEdges.append(( geomEdges.pop( iE ), same1 ))
found = True
break
assert found
sortedEdges.reverse()
# put nodes on edges in a right order
nodes = []
for edge, isForward in sortedEdges:
v1,v2 = geompy.SubShapeAll( edge, geompy.ShapeType["VERTEX"])
edgeNodes = mesh.GetSubMeshNodesId( v2, all=False ) + \
mesh.GetSubMeshNodesId( edge, all=False ) + \
mesh.GetSubMeshNodesId( v1, all=False )
if not isForward: edgeNodes.reverse()
nodes.extend( edgeNodes[:-1] )
# create nodes inside the geomFace
r1 = 0.6
r2 = 1 - r1
nodesInside = []
for n in nodes:
nXYZ = mesh.GetNodeXYZ( n )
newXYZ = np.add( np.multiply( r1, gcXYZ ), np.multiply( r2, nXYZ ))
nodesInside.append( mesh.AddNode( newXYZ[0], newXYZ[1], newXYZ[2] ))
mesh.SetNodeOnFace( nodesInside[-1], geomFace, 0, 0 )
# find out orientation of faces to create
# geomFace normal
faceNorm = geompy.GetNormal( geomFace )
v1,v2 = [ geompy.PointCoordinates( v ) \
for v in geompy.SubShapeAll( faceNorm, geompy.ShapeType["VERTEX"]) ]
faceNormXYZ = np.subtract( v2, v1 )
outDirXYZ = np.subtract( v1, [ 50, 50, 50 ] )
if np.dot( faceNormXYZ, outDirXYZ ) < 0: # reversed face
faceNormXYZ = np.multiply( -1., faceNormXYZ )
# mesh face normal
e1 = np.subtract( mesh.GetNodeXYZ( nodes[0] ), mesh.GetNodeXYZ( nodes[1] ))
e2 = np.subtract( mesh.GetNodeXYZ( nodes[0] ), mesh.GetNodeXYZ( nodesInside[0] ))
meshNorm = np.cross( e1, e2 )
# faces orientation
reverse = ( np.dot( faceNormXYZ, meshNorm ) < 0 )
# create mesh faces
iN = len( nodes )
while iN:
n1, n2, n3, n4 = nodes[iN-1], nodes[iN-2], nodesInside[iN-2], nodesInside[iN-1]
iN -= 1
if reverse:
f = mesh.AddFace( [n1, n2, n3, n4] )
else:
f = mesh.AddFace( [n4, n3, n2, n1] )
# new faces must be assigned to geometry to allow 3D algorithm finding them
mesh.SetMeshElementOnShape( f, geomFace )
if reverse:
nodesInside.reverse()
polygon = mesh.AddPolygonalFace( nodesInside )
mesh.SetMeshElementOnShape( polygon, geomFace )
return
# create geometry and get faces to mesh with my2DMeshing()
box = geompy.MakeBoxDXDYDZ( 100, 100, 100 )
f1 = geompy.SubShapeAll( box, geompy.ShapeType["FACE"])[0]
f2 = geompy.GetOppositeFace( box, f1 )
geompy.addToStudy( box, "box" )
geompy.addToStudy( f1, "f1" )
geompy.addToStudy( f2, "f2" )
# compute 1D mesh
mesh = smesh.Mesh( box )
mesh.Segment().NumberOfSegments( 5 )
mesh.Compute()
# compute 2D mesh
mesh.Quadrangle()
mesh.UseExistingFaces(f1) # UseExistingFaces() allows using my2DMeshing()
mesh.UseExistingFaces(f2)
my2DMeshing( f1 )
my2DMeshing( f2 )
assert mesh.Compute()
# compute 3D mesh
mesh.Prism()
assert mesh.Compute()
\endcode
Resulting mesh:
\image html use_existing_face_sample_mesh.png
*/