From: eap Date: Wed, 20 Oct 2010 14:20:45 +0000 (+0000) Subject: 0020749: EDF 1291 SMESH : Create 2D Mesh from 3D improvement X-Git-Tag: V5_1_5rc1~13 X-Git-Url: http://git.salome-platform.org/gitweb/?a=commitdiff_plain;h=cf145e36af4ce4f324899571eab10748a114fb4d;p=modules%2Fsmesh.git 0020749: EDF 1291 SMESH : Create 2D Mesh from 3D improvement update doc --- diff --git a/doc/salome/gui/SMESH/images/2d_from_3d_menu.png b/doc/salome/gui/SMESH/images/2d_from_3d_menu.png index ec5117214..acb7b349e 100644 Binary files a/doc/salome/gui/SMESH/images/2d_from_3d_menu.png and b/doc/salome/gui/SMESH/images/2d_from_3d_menu.png differ diff --git a/doc/salome/gui/SMESH/input/make_2dmesh_from_3d.doc b/doc/salome/gui/SMESH/input/make_2dmesh_from_3d.doc index ada914ec1..9d334340f 100644 --- a/doc/salome/gui/SMESH/input/make_2dmesh_from_3d.doc +++ b/doc/salome/gui/SMESH/input/make_2dmesh_from_3d.doc @@ -1,22 +1,60 @@ /*! -\page make_2dmesh_from_3d_page Create 2D mesh from 3D +\page make_2dmesh_from_3d_page Generate boundary elements -\n This functionality allows to generate 2D mesh elements as a skin -on the existing 3D mesh elements. +\n This functionality allows to generate mesh elements on borders of +elements of higher dimension. -To generate 2D mesh: + +To generate border elements:
    -
  1. From the Modification menu choose "Create 2D mesh from 3D" +
  2. From the Modification menu choose "Create boundary elements" item, or choose from the popup menu. \image html 2d_from_3d_menu.png - -The algorithm detects boundary volume faces without connections to -other volumes and creates 2D mesh elements on face nodes. If the mesh -already contains 2D elements on the detected nodes, new elements are not -created. The the resulting dialog shows mesh information statistics -about the newly created 2D mesh elements. +The following dialog box will appear: +\image html 2d_from_3d_dlg.png +
    3. +
  3. Check in the dialog box one of three radio buttons corresponding to +the type of operation you would like to perform.
    4. +
  4. Fill the other fields available in the dialog box.
    5. +
  5. Click the \b Apply or Apply and Close button to perform the operation.
+\n "Create boundary elements" dialog allows creation of boundary elements +of three types. + +Here free facet means a facet shared by only one volume, free edge +means an edge shared by only one mesh face. + +In this dialog: + +
See Also a sample TUI Script of a \ref tui_make_2dmesh_from_3d "Create boundary elements" operation. + */ diff --git a/doc/salome/gui/SMESH/input/modifying_meshes.doc b/doc/salome/gui/SMESH/input/modifying_meshes.doc index 0eb82ceb6..45e746da4 100644 --- a/doc/salome/gui/SMESH/input/modifying_meshes.doc +++ b/doc/salome/gui/SMESH/input/modifying_meshes.doc @@ -47,7 +47,7 @@ of the selected node or edge.
  • Apply \subpage pattern_mapping_page "pattern mapping".
  • \subpage convert_to_from_quadratic_mesh_page "Convert regular mesh to quadratic", or vice versa.
    • -
  • \subpage make_2dmesh_from_3d_page "Create 2D mesh from 3D".
    • +
  • \subpage make_2dmesh_from_3d_page "Generate boundary elements".
    • diff --git a/doc/salome/gui/SMESH/input/tui_transforming_meshes.doc b/doc/salome/gui/SMESH/input/tui_transforming_meshes.doc index e50fcda36..87d75b672 100644 --- a/doc/salome/gui/SMESH/input/tui_transforming_meshes.doc +++ b/doc/salome/gui/SMESH/input/tui_transforming_meshes.doc @@ -421,4 +421,167 @@ if salome.sg.hasDesktop(): salome.sg.updateObjBrowser(0) \endcode +
    +\anchor tui_make_2dmesh_from_3d +

    Create boundary elements

    + +\code +# The goal of this feature is to enable the following use cases: +# 1) The mesh MESH1 with 3D cells does not have or have only a part of its skin (2D cells): +# 1.1) Add the 2D skin (missing 2D cells) to MESH1 (what it's done now by the algorithm). +# 1.2) Create new 3D Mesh MESH2 that consists of MESH1 and added 2D skin cells. +# 1.3) Create new 2D Mesh MESH3 that consists of only the 2D skin cells. +# 2) The mesh MESH1 with 3D cells has all its skin (2D cells): +# Create new 2D Mesh MESH3 that consists of only the 2D skin cells. +# +# In all cases an option to create a group containing these 2D skin cells should be available. + +from smesh import * + +box = geompy.MakeBoxDXDYDZ(1,1,1) +geompy.addToStudy(box,"box") +boxFace = geompy.SubShapeAll(box, geompy.ShapeType["FACE"])[0] +geompy.addToStudyInFather(box,boxFace,"boxFace") + +MESH1 = Mesh(box,"MESH1") +MESH1.AutomaticHexahedralization() + +init_nb_edges = MESH1.NbEdges() +init_nb_faces = MESH1.NbFaces() +init_nb_volumes = MESH1.NbVolumes() + +# ========================================================================================= +# 1) The mesh MESH1 with 3D cells does not have or have only a part of its skin (2D cells) +# ========================================================================================= +# remove some faces +all_faces = MESH1.GetElementsByType(SMESH.FACE) +rm_faces = all_faces[:init_nb_faces/5] + all_faces[4*init_nb_faces/5:] +MESH1.RemoveElements(rm_faces) +assert(MESH1.NbFaces() == init_nb_faces-len(rm_faces)) + +# 1.1) Add the 2D skin (missing 2D cells) to MESH1 +# ------------------------------------------------- +# add missing faces +# 1.1.1) to the whole mesh +m,g = MESH1.MakeBoundaryMesh(MESH1) +assert(init_nb_faces == MESH1.NbFaces()) +assert(init_nb_edges == MESH1.NbEdges()) +assert(m) +assert(not g) + +# 1.1.2) to some elements +MESH1.RemoveElements(rm_faces) +MESH1.MakeBoundaryMesh([]) +assert(init_nb_faces != MESH1.NbFaces()) +volumes = MESH1.GetElementsByType(SMESH.VOLUME) +for v in volumes: + MESH1.MakeBoundaryMesh([v]) +assert(init_nb_faces == MESH1.NbFaces()) +assert(init_nb_edges == MESH1.NbEdges()) + +# 1.1.3) to group of elements +volGroup1 = MESH1.CreateEmptyGroup(SMESH.VOLUME, "volGroup1") +volGroup1.Add( volumes[: init_nb_volumes/2]) +volGroup2 = MESH1.CreateEmptyGroup(SMESH.VOLUME, "volGroup2") +volGroup1.Add( volumes[init_nb_volumes/2:]) +MESH1.RemoveElements(rm_faces) +MESH1.MakeBoundaryMesh(volGroup1) +MESH1.MakeBoundaryMesh(volGroup2) +assert(init_nb_faces == MESH1.NbFaces()) +assert(init_nb_edges == MESH1.NbEdges()) + +# 1.1.4) to submesh. +# The submesh has no volumes, so check if it pass w/o a crash and does not create +# missing faces +faceSubmesh = MESH1.GetSubMesh( boxFace, "boxFace" ) +MESH1.RemoveElements(rm_faces) +MESH1.MakeBoundaryMesh(faceSubmesh) +assert(init_nb_faces != MESH1.NbFaces()) + +# check group creation +MESH1.RemoveElements(rm_faces) +groupName = "added to mesh" +m,group = MESH1.MakeBoundaryMesh(MESH1,groupName=groupName) +assert(group) +assert(group.GetName() == groupName) +assert(group.Size() == len(rm_faces)) + + +# 1.2) Create new 3D Mesh MESH2 that consists of MESH1 and added 2D skin cells. +# ------------------------------------------------------------------------------ +MESH1.RemoveElements(rm_faces) +meshName = "MESH2" +MESH2,group = MESH1.MakeBoundaryMesh(MESH1,meshName=meshName,toCopyElements=True) +assert(MESH2) +assert(MESH2.GetName() == meshName) +assert(MESH2.NbVolumes() == MESH1.NbVolumes()) +assert(MESH2.NbFaces() == len(rm_faces)) + +# check group creation +MESH1.RemoveElements(rm_faces) +MESH2,group = MESH1.MakeBoundaryMesh(MESH1,meshName="MESH2_0", + groupName=groupName,toCopyElements=True) +assert(group) +assert(group.GetName() == groupName) +assert(group.Size() == len(rm_faces)) +assert(group.GetMesh()._is_equivalent(MESH2.GetMesh())) + +# 1.3) Create new 2D Mesh MESH3 that consists of only the 2D skin cells. +# ----------------------------------------------------------------------- +MESH1.RemoveElements(rm_faces) +meshName = "MESH3" +MESH3,group = MESH1.MakeBoundaryMesh(MESH1,meshName=meshName,toCopyExistingBondary=True) +assert(MESH3) +assert(not group) +assert(MESH3.GetName() == meshName) +assert(MESH3.NbVolumes() == 0) +assert(MESH3.NbFaces() == init_nb_faces) + +# check group creation +MESH1.RemoveElements(rm_faces) +MESH3,group = MESH1.MakeBoundaryMesh(MESH1,meshName=meshName, + groupName=groupName, toCopyExistingBondary=True) +assert(group) +assert(group.GetName() == groupName) +assert(group.Size() == len(rm_faces)) +assert(group.GetMesh()._is_equivalent(MESH3.GetMesh())) +assert(MESH3.NbFaces() == init_nb_faces) + +# ================================================================== +# 2) The mesh MESH1 with 3D cells has all its skin (2D cells) +# Create new 2D Mesh MESH3 that consists of only the 2D skin cells. +# ================================================================== +MESH1.MakeBoundaryMesh(MESH1) +MESH3,group = MESH1.MakeBoundaryMesh(MESH1,meshName=meshName,toCopyExistingBondary=True) +assert(MESH3) +assert(not group) +assert(MESH3.NbVolumes() == 0) +assert(MESH3.NbFaces() == init_nb_faces) + +# check group creation +MESH3,group = MESH1.MakeBoundaryMesh(MESH1,meshName=meshName, + groupName=groupName, toCopyExistingBondary=True) +assert(group) +assert(group.GetName() == groupName) +assert(group.Size() == 0) +assert(group.GetMesh()._is_equivalent(MESH3.GetMesh())) +assert(MESH3.NbFaces() == init_nb_faces) + +# ================ +# Make 1D from 2D +# ================ + +MESH1.Clear() +MESH1.Compute() +MESH1.RemoveElements( MESH1.GetElementsByType(SMESH.EDGE)) + +rm_faces = faceSubmesh.GetIDs()[:2] # to remove few adjacent faces +nb_missing_edges = 2 + 2*len(rm_faces) + +MESH1.RemoveElements(rm_faces) +mesh,group = MESH1.MakeBoundaryMesh(MESH1, BND_1DFROM2D) +assert( MESH1.NbEdges() == nb_missing_edges ) + + +\endcode */