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About "Use Existing Faces" stub algorithm
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@ -62,6 +62,9 @@ There is also a number of more specific algorithms:
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<li>\subpage prism_3d_algo_page "for meshing prismatic shapes"</li>
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<li>\subpage radial_quadrangle_1D2D_algo_page "for meshing special 2d faces (circles and part of circles)"</li>
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</ul>
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\ref use_existing_anchor "Use existing edges" and
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\ref use_existing_anchor "Use existing faces" algorithms can be
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used to create an 1D or a 2D mesh in a python script.
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\ref constructing_meshes_page "Constructing meshes" page describes in
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detail how to apply meshing algorithms.
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@ -2,106 +2,142 @@
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\page constructing_meshes_page Constructing meshes
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\n Construction of a mesh consists of:
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\n Construction of a mesh on some geometry consists of:
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<ul>
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<li>Selecting a geometrical object for meshing</li>
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<li>Applying \subpage basic_meshing_algos_page "meshing algorithms" and
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\subpage about_hypo_page "hypotheses" which will be used at computation of
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this mesh.</li>
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<li> \ref create_mesh_anchor "Creating of a mesh object"</li>
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<li> \ref evaluate_anchor "Evaluating mesh size"</li>
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<li> \ref preview_anchor "Previewing the mesh"</li>
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<li> \ref submesh_order_anchor "Changing submesh priority"</li>
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<li> \ref compute_anchor "Computing the mesh"</li>
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</ul>
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Mesh can be \ref use_existing_anchor "computed using your own meshing algorithms"
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written in Python.
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\anchor create_mesh_anchor
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<h2>Creation of a mesh object</h2>
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<em>To construct a mesh:</em>
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<ol>
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<li>In the \b Mesh menu select <b>Create Mesh</b> or click <em>"Create
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Mesh"</em> button in the toolbar.
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<li>Select a geometrical object for meshing.</li>
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<li>In the \b Mesh menu select <b>Create Mesh</b> or click <em>"Create
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Mesh"</em> button in the toolbar.
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\image html image32.png
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<center><em>"Create Mesh" button</em></center>
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\image html image32.png
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<em>"Create Mesh" button</em>
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The following dialog box will appear:
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The following dialog box will appear:
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\image html createmesh-inv.png
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</li>
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<li>For example, you need to mesh a 3d object.
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\n First, type the name for your mesh in the "Name" box, by default,
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it is "Mesh_1". Then select the object you wish to mesh in the Object
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Browser and click the "Add" button (if name of the object not yet
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appeared in \b Geometry field).
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\image html createmesh-inv.png
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<br>
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</li>
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<li>Apply \subpage basic_meshing_algos_page "meshing algorithms" and
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\subpage about_hypo_page "hypotheses" which will be used at computation of
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this mesh.
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\image html image120.png
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<center><em>"Add" button</em></center>
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For example, you need to mesh a 3D object.
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Now you can define 1d Algorithm and 1d Hypotheses, which will be
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applied to the edges of your object. (Note that any object has edges,
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even if their existence is not apparent, for example, a sphere has 4
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edges). Click the <em>"Add Hypothesis"</em> button to add a
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hypothesis.
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First, type the name for your mesh in the \b Name box, by default,
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it is "Mesh_1". Then select the geometrical object you wish to
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mesh in the Object Browser and click "Select" button near \b Geometry
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field (if name of the object not yet appeared in \b Geometry field).
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\image html image121.png
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<center><em>"Add Hypothesis" button</em></center>
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\image html image120.png
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<em>"Select" button</em>
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Click the <em>"Edit Hypothesis"</em> button to define values for the
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current hypothesis.
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Now you can define 3D Algorithm and 3D Hypotheses, which will be
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applied to solids of your geometrical object. Click the <em>"Add
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Hypothesis"</em> button to add a hypothesis.
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\image html image122.png
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<center><em>"Edit Hypothesis" button</em></center>
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\image html image121.png
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<em>"Add Hypothesis" button</em>
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The use of additional hypotheses is optional (i.e. you may leave
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"None" in this box).
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Click the <em>"Edit Hypothesis"</em> button to change values for the
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current hypothesis.
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Proceed in the same way with 2d and 3d Algorithms and Hypotheses, note
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that the choice of hypotheses depends on the algorithm. There must be
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one Algorithm and zero or several Hypotheses for each dimension of your
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object (most standard 2D and 3D algorithms can work without
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hypotheses using some default parameters),
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otherwise you will not get any mesh at all. Of course, if you
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wish to mesh a face, which is a 2d object, you don't need to define 3d
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Algorithm and Hypotheses.
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\n In the <b>Object Browser</b> the structure of the new mesh will be
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displayed as follows:
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\image html image122.png
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<em>"Edit Hypothesis" button</em>
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\image html image88.jpg
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Most standard 2D and 3D algorithms can work without hypotheses
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using some default parameters. The use of additional hypotheses
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is optional (i.e. you may leave "None" in this box).
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It contains:
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<ul>
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<li>a reference to the geometrical object on the basis of which the mesh has been constructed;</li>
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<li><b>Applied hypotheses</b> folder containing the references to the
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hypotheses applied to the construction of the mesh;</li>
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<li><b>Applied algorithms</b> folder containing the references to the
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algorithms applied to the construction of the mesh.</li>
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</ul>
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<br>
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There is an alternative way to create a mesh on an object simply by
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clicking <b>Assign a set of hypotheses</b> button and selecting among
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pre-defined sets of hypotheses. In addition to the standard
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sets of hypotheses, it is possible to create custom sets by editing
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CustomMeshers.xml file located in the home directory. CustomMeshers.xml
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file must describe sets of hypotheses in the
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same way as ${SMESH_ROOT_DIR}/share/salome/resources/smesh/StdMeshers.xml
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file does (sets of hypotheses are enclosed between <hypotheses-set-group>
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tags).
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\image html hypo_sets.png
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<center>List of sets of hypotheses: <em>[custom]</em> is automatically added to the sets defined
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by the user</center>
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</li>
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Proceed in the same way with 2D and 1D Algorithms and Hypotheses that
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will be used to mesh faces and edges of your geometry. (Note
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that any object has edges, even if their existence is not
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apparent, for example, a sphere has 4 edges). Note that the
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choice of hypotheses and of an algorithm of lower dimension depends on
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the algorithm.
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\anchor preview_mesh_anchor
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Some algorithms generate mesh of several dimensions while others, of
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only one dimension. In the latter case there must be one Algorithm and zero or several
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Hypotheses for each dimension of your object, otherwise you will
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not get any mesh at all. Of course, if you wish to mesh a face,
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which is a 2D object, you don't need to define 3D Algorithm and
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Hypotheses.
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<li> After the mesh object is created and all hypotheses are assigned and
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before the mesh computation, it is possible to see the mesh preview.
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In the <b>Object Browser</b> the structure of the new mesh will be
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displayed as follows:
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\image html image88.jpg
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It contains:
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<ul>
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<li>a reference to the geometrical object on the basis of
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which the mesh has been constructed;</li>
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<li><b>Applied hypotheses</b> folder containing the references
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to the hypotheses applied at the construction of the mesh;</li>
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<li><b>Applied algorithms</b> folder containing the references
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to the algorithms applied at the construction of the mesh.</li>
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</ul>
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There is an alternative way to assign Algorithms and Hypotheses by
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clicking <b>Assign a set of hypotheses</b> button and selecting among
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pre-defined sets of hypotheses. In addition to the standard
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sets of hypotheses, it is possible to create custom sets by editing
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CustomMeshers.xml file located in the home directory. CustomMeshers.xml
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file must describe sets of hypotheses in the
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same way as ${SMESH_ROOT_DIR}/share/salome/resources/smesh/StdMeshers.xml
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file does (sets of hypotheses are enclosed between <hypotheses-set-group>
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tags).
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\image html hypo_sets.png
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List of sets of hypotheses: <em>[custom]</em>
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automatically added to the sets defined by the user
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</li>
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</ol>
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Consider trying a sample script for construction of a mesh from our
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\ref tui_creating_meshes_page "TUI Scripts" section.
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\anchor evaluate_anchor
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<h2>Evaluating mesh size</h2>
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After the mesh object is created and all hypotheses are assigned and
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before \ref compute_anchor "Compute" operation, it is possible to
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calculate the eventual mesh size. For this, select the mesh in
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the <b>Object Browser</b> and from the \b Mesh menu select \b
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Evaluate. The result of evaluation will be displayed in the following
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information box:
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\image html mesh_evaluation_succeed.png
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\anchor preview_anchor
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<h2>Previewing the mesh</h2>
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Before \ref compute_anchor "the mesh computation", it is also possible
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to see the mesh preview.
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For this, select the mesh in the Object Browser. From the \b Mesh menu
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select \b Preview or click "Preview" button in the
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toolbar or activate "Preview" item from the pop-up menu.
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select \b Preview or click "Preview" button in the toolbar or activate
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"Preview" item from the pop-up menu.
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\image html mesh_precompute.png
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<center><em>"Preview" button</em></center>
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<em>"Preview" button</em>
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Select <b>1D mesh</b> or <b>2D mesh</b> preview mode in the Preview dialog.
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\image html preview_mesh_1D.png "1D mesh preview shows nodes computed on geometry edges"
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<br>
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\image html preview_mesh_2D.png "2D mesh preview shows edge mesh elements, computed on geometry faces"
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<b>Compute</b> button computes the whole mesh.
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@ -111,17 +147,105 @@ created mesh elements appers:
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\image html preview_tmp_data.png
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These elenents can be reused in the next mesh computation.
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</li>
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These elements can be kept in the mesh.
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<li>It is equally possible to skip the Preview and \b Compute the mesh
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after the hypotheses are assigned. For this, select your mesh in the <b>Object
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Browser</b>. From the \b Mesh menu select \b Compute or click "Compute" button of the
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toolbar.
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\anchor submesh_order_anchor
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<h2>Changing submesh priority</h2>
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If the mesh contains concurrent \ref constructing_submeshes_page "submeshes",
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it is possible to change the priority of their computation, i.e. to
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change the priority of applying algorithms to the shared sub-shapes of
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the Mesh shape.
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<em>To change submesh priority:</em>
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Choose "Change submesh priority" from the Mesh menu or a pop-up
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menu. The opened dialog shows a list of submeshes in the order of
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their priority.
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There is an example of submesh order modifications of the Mesh created on a Box
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shape. The main Mesh object:
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<ul>
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<li><i>1D</i> <b>Wire discretisation</b> with <b>Number of Segments</b>=20</li>
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<li><i>2D</i> <b>Triangle (Mefisto)</b> with Hypothesis<b>Max Element Area</b>
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</li>
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</ul>
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The first submesh object <b>Submesh_1</b> created on <b>Face_1</b> is:
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<ul>
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<li><i>1D</i> <b>Wire discretisation</b> with <b>Number of Segments</b>=4</li>
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<li><i>2D</i> <b>Triangle (Mefisto)</b> with Hypothesis<b>MaxElementArea</b>=1200</li>
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</ul>
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The second submesh object <b>Submesh_2</b> created on <b>Face_2</b> is:
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<ul>
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<li><i>1D</i> <b>Wire discretisation</b> with <b>Number of Segments</b>=8</li>
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<li><i>2D</i> <b>Triangle (Mefisto)</b> with Hypothesis<b>MaxElementArea</b>=1200</li>
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</ul>
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And the last submesh object <b>Submesh_3</b> created on <b>Face_3</b> is:
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<ul>
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<li><i>1D</i> <b>Wire discretisation</b> with <b>Number of Segments</b>=12</li>
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<li><i>2D</i> <b>Triangle (Mefisto)</b> with Hypothesis<b>MaxElementArea</b>=1200</li>
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</ul>
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The sub-meshes become concurrent if they share sub-shapes that can be
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meshed with different algorithms (or different hypothesises). In the
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example, we have three submeshes with concurrent algorithms, because
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they have different hypotheses.
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The first mesh computation is made with:
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<center>
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\image html mesh_order_123.png
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<em>"Mesh order SubMesh_1, SubMesh_2, SubMesh_3"</em></center>
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<center>
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\image html mesh_order_123_res.png
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<em>"Result mesh with order SubMesh_1, SubMesh_2, SubMesh_3 "</em></center>
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The next mesh computation is made with:
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<center>
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\image html mesh_order_213.png
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<em>"Mesh order SubMesh_2, SubMesh_1, SubMesh_3"</em></center>
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<center>
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\image html mesh_order_213_res.png
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<em>"Result mesh with order SubMesh_2, SubMesh_1, SubMesh_3 "</em></center>
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And the last mesh computation is made with:
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<center>
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\image html mesh_order_321.png
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<em>"Mesh order SubMesh_3, SubMesh_2, SubMesh_1"</em></center>
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<center>\image html mesh_order_321_res.png
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<em>"Result mesh with order SubMesh_3, SubMesh_2, SubMesh_1 "</em></center>
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As we can see, each mesh computation has a different number of result
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elements and a different mesh discretisation on the shared edges (the edges
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that are shared between <b>Face_1</b>, <b>Face_2</b> and <b>Face_3</b>)
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Additionally, submesh priority (the order of applied algorithms) can
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be modified not only in a separate dialog box, but also in
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the <b>Preview</b>. This helps to preview different mesh results,
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modifying the order of submeshes.
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<center>
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\image html mesh_order_preview.png
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<em>"Preview with submesh priority list box"</em></center>
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If there are no concurrent submeshes under the Mesh object, the user
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will see the following information.
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<center>
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\image html mesh_order_no_concurrent.png
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<em>"No concurrent submeshes detected"</em></center>
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\anchor compute_anchor
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<h2>Computing the mesh</h2>
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It is equally possible to skip \ref evaluate_anchor "the Evaluation"
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and \ref preview_anchor "the Preview" and to \b Compute the mesh after
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the hypotheses are assigned. For this, select your mesh in
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the <b>Object Browser</b>. From the \b Mesh menu select \b Compute or
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click "Compute" button of the toolbar.
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\image html image28.png
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<center><em>"Compute" button</em></center>
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<em>"Compute" button</em>
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The Mesh Computation information box appears.
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@ -133,9 +257,12 @@ failure is provided.
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\image html meshcomputationfail.png
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After you select the error, <b>Show Sub-shape</b> button allows
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visualizing the geometrical entity that causes it.
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visualizing in magenta the geometrical entity that causes it.
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\image html failed_computation.png
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<em>3D algorithm failed to compute mesh on a box shown using <b>Show
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Sub-shape</b> button</em>
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\image html failed_computation.png "Example of the invalid input mesh"
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\note Mesh Computation Information box does not appear if you set
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"Mesh computation/Show a computation result notification" preference
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@ -149,104 +276,38 @@ failed, in GEOM component as a child of the mesh geometry, which
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allows analyzing the problem geometry and creating a submesh on it in
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order to locally tune hypotheses.
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<b>NOTE</b> It is possible to define a 1D or a 2D mesh in a
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python script and then use such submeshes in the construction of a 3D
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mesh. For this, there exist two algorithms: <b>Use existing edges</b> and <b>Use
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existing faces</b>. They are not entirely usable from the GUI, so a
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mesh created using these algorithms should be exported into a python
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script, edited and then imported into the GUi.
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If a cause of failure is an invalid input mesh and the algorithm has
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provided information on what mesh entities are bad <b>Show bad Mesh</b>
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button appears in the dialog. Clicked, it shows bad mesh entities in
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the Viewer in magenta. Sometimes the shown mesh entities are too small
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or/and hidden by other mesh elements, to see them it can be helpful to
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switch the mesh to Wireframe visualization mode or to switch off
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visualization of faces and volumes (if any).
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<li>It is possible to calculate the eventual mesh size
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before \b Compute operation. For this, select the mesh in the <b>Object
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Browser</b> and from the \b Mesh menu select \b Evaluate. The result of
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evaluation will be displayed in the following information box:
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\anchor use_existing_anchor
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<h2>"Use existing edges" and "Use existing faces" algorithms</h2>
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\image html mesh_evaluation_succeed.png
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</li>
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\anchor mesh_order_anchor
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<li>
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If the mesh contains concurrent submeshes, it is possible to change
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the priority of their computation, i.e. to change the priority of
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applying algorithms to the shared sub-shapes of the Mesh shape.</li>
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<em>To change submesh priority:</em>
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<li>Choose "Change submesh priority" from the Mesh menu or a popup menu. The opened dialogue
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shows a list of submeshes in the order of their priority.
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There is an example of submesh order modifications of the Mesh created on a Box
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shape. The main Mesh object:
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It is possible to create an 1D or a 2D mesh in a python script
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(using <em>AddNode, AddEdge</em> and <em>AddFace</em> commands) and
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then use such sub-meshes in the construction of a 2D or a 3D mesh. For
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this, there exist two algorithms: <b>Use existing edges</b> and <b>Use
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existing faces</b>. Scenario of their usage is following. For
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example, you want to use standard algorithms to generate 1D and 3D
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meshes and to create 2D mesh by your python code. Then you
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<ul>
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<li><i>1D</i> <b>Wire discretisation</b> with <b>Number of Segments</b>=20</li>
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<li><i>2D</i> <b>Triangle (Mefisto)</b> with Hypothesis<b>Max Element Area</b>
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</li>
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</ul>
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The first submesh object <b>Submesh_1</b> created on <b>Face_1</b>
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is:
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<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>
|
||||
|
||||
*/
|
||||
|
||||
@ -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:
|
||||
|
||||
124
doc/salome/gui/SMESH/input/tui_use_existing_faces.doc
Normal file
124
doc/salome/gui/SMESH/input/tui_use_existing_faces.doc
Normal file
@ -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
|
||||
|
||||
*/
|
||||
Loading…
Reference in New Issue
Block a user