/*! \page tui_defining_hypotheses_page Defining Hypotheses and Algorithms

Defining 1D Hypotheses


\anchor tui_1d_arithmetic

1D Arithmetic

\code import geompy import smesh # create a box box = geompy.MakeBoxDXDYDZ(10., 10., 10.) geompy.addToStudy(box, "Box") # create a hexahedral mesh on the box hexa = smesh.Mesh(box, "Box : hexahedrical mesh") # create a Regular 1D algorithm for edges algo1D = hexa.Segment() # optionally reverse node distribution on certain edges allEdges = geompy.SubShapeAllSortedIDs( box, geompy.ShapeType["EDGE"]) reversedEdges = [ allEdges[0], allEdges[4] ] # define "Arithmetic1D" hypothesis to cut all edges in several segments with increasing arithmetic length algo1D.Arithmetic1D(1, 4, reversedEdges) # create a quadrangle 2D algorithm for faces hexa.Quadrangle() # create a hexahedron 3D algorithm for solids hexa.Hexahedron() # compute the mesh hexa.Compute() \endcode
\anchor tui_deflection_1d

Deflection 1D and Number of Segments

\code import geompy import smesh # create a face from arc and straight segment px = geompy.MakeVertex(100., 0. , 0. ) py = geompy.MakeVertex(0. , 100., 0. ) pz = geompy.MakeVertex(0. , 0. , 100.) exy = geompy.MakeEdge(px, py) arc = geompy.MakeArc(py, pz, px) wire = geompy.MakeWire([exy, arc]) isPlanarFace = 1 face1 = geompy.MakeFace(wire, isPlanarFace) geompy.addToStudy(face1,"Face1") # get edges from the face e_straight,e_arc = geompy.SubShapeAll(face1, geompy.ShapeType["EDGE"]) geompy.addToStudyInFather(face1, e_arc, "Arc Edge") # create hexahedral mesh hexa = smesh.Mesh(face1, "Face : triangle mesh") # define "NumberOfSegments" hypothesis to cut a straight edge in a fixed number of segments algo1D = hexa.Segment() algo1D.NumberOfSegments(6) # define "MaxElementArea" hypothesis algo2D = hexa.Triangle() algo2D.MaxElementArea(70.0) # define a local "Deflection1D" hypothesis on the arc algo_local = hexa.Segment(e_arc) algo_local.Deflection1D(1.0) # compute the mesh hexa.Compute() \endcode
\anchor tui_start_and_end_length

Start and End Length

\code from geompy import * import smesh # create a box box = MakeBoxDXDYDZ(10., 10., 10.) addToStudy(box, "Box") # get one edge of the box to put local hypothesis on p5 = MakeVertex(5., 0., 0.) EdgeX = GetEdgeNearPoint(box, p5) addToStudyInFather(box, EdgeX, "Edge [0,0,0 - 10,0,0]") # create a hexahedral mesh on the box hexa = smesh.Mesh(box, "Box : hexahedrical mesh") # set algorithms algo1D = hexa.Segment() hexa.Quadrangle() hexa.Hexahedron() # define "NumberOfSegments" hypothesis to cut an edge in a fixed number of segments algo1D.NumberOfSegments(4) # create a local hypothesis algo_local = hexa.Segment(EdgeX) # define "StartEndLength" hypothesis to cut an edge in several segments with increasing geometric length algo_local.StartEndLength(1, 6) # define "Propagation" hypothesis that propagates all other hypothesis # on all edges on the opposite side in case of quadrangular faces algo_local.Propagation() # compute the mesh hexa.Compute() \endcode
\anchor tui_average_length

Average Length

\code from geompy import * import smesh # create a box box = MakeBoxDXDYDZ(10., 10., 10.) addToStudy(box, "Box") # get one edge of the box to put local hypothesis on p5 = MakeVertex(5., 0., 0.) EdgeX = GetEdgeNearPoint(box, p5) addToStudyInFather(box, EdgeX, "Edge [0,0,0 - 10,0,0]") # create a hexahedral mesh on the box hexa = smesh.Mesh(box, "Box : hexahedrical mesh") # set algorithms algo1D = hexa.Segment() hexa.Quadrangle() hexa.Hexahedron() # define "NumberOfSegments" hypothesis to cut all edges in a fixed number of segments algo1D.NumberOfSegments(4) # create a sub-mesh algo_local = hexa.Segment(EdgeX) # define "LocalLength" hypothesis to cut an edge in several segments with the same length algo_local.LocalLength(2.) # define "Propagation" hypothesis that propagates all other hypothesis # on all edges on the opposite side in case of quadrangular faces algo_local.Propagation() # compute the mesh hexa.Compute() \endcode

Defining 2D and 3D hypotheses


\anchor tui_max_element_area

Maximum Element Area

\code import geompy import smesh import salome # create a face px = geompy.MakeVertex(100., 0. , 0. ) py = geompy.MakeVertex(0. , 100., 0. ) pz = geompy.MakeVertex(0. , 0. , 100.) vxy = geompy.MakeVector(px, py) arc = geompy.MakeArc(py, pz, px) wire = geompy.MakeWire([vxy, arc]) isPlanarFace = 1 face = geompy.MakeFace(wire, isPlanarFace) # add the face in the study id_face = geompy.addToStudy(face, "Face to be meshed") # create a mesh tria_mesh = smesh.Mesh(face, "Face : triangulation") # define 1D meshing: algo = tria_mesh.Segment() algo.NumberOfSegments(20) # define 2D meshing: # assign triangulation algorithm algo = tria_mesh.Triangle() # apply "Max Element Area" hypothesis to each triangle algo.MaxElementArea(100) # compute the mesh tria_mesh.Compute() \endcode
\anchor tui_max_element_volume

Maximum Element Volume

\code import geompy import smesh # create a cylinder cyl = geompy.MakeCylinderRH(30., 50.) geompy.addToStudy(cyl, "cyl") # create a mesh on the cylinder tetra = smesh.Mesh(cyl, "Cylinder : tetrahedrical mesh") # assign algorithms algo1D = tetra.Segment() algo2D = tetra.Triangle() algo3D = tetra.Tetrahedron(smesh.NETGEN) # assign 1D and 2D hypotheses algo1D.NumberOfSegments(7) algo2D.MaxElementArea(150.) # assign Max Element Volume hypothesis algo3D.MaxElementVolume(200.) # compute the mesh ret = tetra.Compute() if ret == 0: print "probleme when computing the mesh" else: print "Computation succeded" \endcode
\anchor tui_length_from_edges

Length from Edges

\code import geompy import smesh # create sketchers sketcher1 = geompy.MakeSketcher("Sketcher:F 0 0:TT 70 0:TT 70 70:TT 0 70:WW") sketcher2 = geompy.MakeSketcher("Sketcher:F 20 20:TT 50 20:TT 50 50:TT 20 50:WW") # create a face from two wires isPlanarFace = 1 face1 = geompy.MakeFaces([sketcher1, sketcher2], isPlanarFace) geompy.addToStudy(face1, "Face1") # create a mesh tria = smesh.Mesh(face1, "Face : triangle 2D mesh") # Define 1D meshing algo1D = tria.Segment() algo1D.NumberOfSegments(2) # create and assign the algorithm for 2D meshing with triangles algo2D = tria.Triangle() # create and assign "LengthFromEdges" hypothesis to build triangles based on the length of the edges taken from the wire algo2D.LengthFromEdges() # compute the mesh tria.Compute() \endcode

Defining Additional Hypotheses


\anchor tui_propagation

Propagation

\code from geompy import * import smesh # create a box box = MakeBoxDXDYDZ(10., 10., 10.) addToStudy(box, "Box") # get one edge of the box to put local hypothesis on p5 = MakeVertex(5., 0., 0.) EdgeX = GetEdgeNearPoint(box, p5) addToStudyInFather(box, EdgeX, "Edge [0,0,0 - 10,0,0]") # create a hexahedral mesh on the box hexa = smesh.Mesh(box, "Box : hexahedrical mesh") # set global algorithms and hypotheses algo1D = hexa.Segment() hexa.Quadrangle() hexa.Hexahedron() algo1D.NumberOfSegments(4) # create a sub-mesh with local 1D hypothesis and propagation algo_local = hexa.Segment(EdgeX) # define "Arithmetic1D" hypothesis to cut an edge in several segments with increasing length algo_local.Arithmetic1D(1, 4) # define "Propagation" hypothesis that propagates all other 1D hypotheses # from all edges on the opposite side of a face in case of quadrangular faces algo_local.Propagation() # compute the mesh hexa.Compute() \endcode
\anchor tui_defining_meshing_algos

Defining Meshing Algorithms

\code import geompy import smesh # create a box box = geompy.MakeBoxDXDYDZ(10., 10., 10.) geompy.addToStudy(box, "Box") # 1. Create a hexahedral mesh on the box hexa = smesh.Mesh(box, "Box : hexahedrical mesh") # create a Regular 1D algorithm for edges algo1D = hexa.Segment() # create a quadrangle 2D algorithm for faces algo2D = hexa.Quadrangle() # create a hexahedron 3D algorithm for solids algo3D = hexa.Hexahedron() # define hypotheses algo1D.Arithmetic1D(1, 4) # compute the mesh hexa.Compute() # 2. Create a tetrahedral mesh on the box tetra = smesh.Mesh(box, "Box : tetrahedrical mesh") # create a Regular 1D algorithm for edges algo1D = tetra.Segment() # create a Mefisto 2D algorithm for faces algo2D = tetra.Triangle() # create a Netgen 3D algorithm for solids algo3D = tetra.Tetrahedron(smesh.NETGEN) # define hypotheses algo1D.Arithmetic1D(1, 4) algo2D.LengthFromEdges() # compute the mesh tetra.Compute() # 3. Create a tetrahedral mesh on the box with NETGEN_2D3D algorithm tetraN = smesh.Mesh(box, "Box : tetrahedrical mesh by NETGEN_2D3D") # create a Netgen_2D3D algorithm for solids algo3D = tetraN.Tetrahedron(smesh.FULL_NETGEN) # define hypotheses n23_params = algo3D.Parameters() # compute the mesh tetraN.Compute() \endcode
\anchor tui_projection

Projection Algorithms

\code # Project prisms from one meshed box to another mesh on the same box from smesh import * # Prepare geometry # Create a parallelepiped box = geompy.MakeBoxDXDYDZ(200, 100, 70) geompy.addToStudy( box, "box" ) # Get geom faces to mesh with triangles in the 1ts and 2nd meshes faces = geompy.SubShapeAll(box, geompy.ShapeType["FACE"]) # 2 adjacent faces of the box f1 = faces[2] f2 = faces[0] # face opposite to f2 f2opp = faces[1] # Get vertices used to specify how to associate sides of faces at projection [v1F1, v2F1] = geompy.SubShapeAll(f1, geompy.ShapeType["VERTEX"])[:2] [v1F2, v2F2] = geompy.SubShapeAll(f2, geompy.ShapeType["VERTEX"])[:2] geompy.addToStudyInFather( box, v1F1, "v1F1" ) geompy.addToStudyInFather( box, v2F1, "v2F1" ) geompy.addToStudyInFather( box, v1F2, "v1F2" ) geompy.addToStudyInFather( box, v2F2, "v2F2" ) # Make group of 3 edges of f1 and f2 edgesF1 = geompy.CreateGroup(f1, geompy.ShapeType["EDGE"]) geompy.UnionList( edgesF1, geompy.SubShapeAll(f1, geompy.ShapeType["EDGE"])[:3]) edgesF2 = geompy.CreateGroup(f2, geompy.ShapeType["EDGE"]) geompy.UnionList( edgesF2, geompy.SubShapeAll(f2, geompy.ShapeType["EDGE"])[:3]) geompy.addToStudyInFather( box, edgesF1, "edgesF1" ) geompy.addToStudyInFather( box, edgesF2, "edgesF2" ) # Make the source mesh with prisms src_mesh = Mesh(box, "Source mesh") src_mesh.Segment().NumberOfSegments(9,10) src_mesh.Quadrangle() src_mesh.Hexahedron() src_mesh.Triangle(f1) # triangular sumbesh src_mesh.Compute() # Mesh the box using projection algoritms # Define the same global 1D and 2D hypotheses tgt_mesh = Mesh(box, "Target mesh") tgt_mesh.Segment().NumberOfSegments(9,10,UseExisting=True) tgt_mesh.Quadrangle() # Define Projection 1D algorithm to project 1d mesh elements from group edgesF2 to edgesF1 # It is actually not needed, just a demonstration proj1D = tgt_mesh.Projection1D( edgesF1 ) # each vertex must be at the end of a connected group of edges (or a sole edge) proj1D.SourceEdge( edgesF2, src_mesh, v2F1, v2F2 ) # Define 2D hypotheses to project triangles from f1 face of the source mesh to # f2 face in the target mesh. Vertices specify how to associate sides of faces proj2D = tgt_mesh.Projection2D( f2 ) proj2D.SourceFace( f1, src_mesh, v1F1, v1F2, v2F1, v2F2 ) # 2D hypotheses to project triangles from f2 of target mesh to the face opposite to f2. # Association of face sides is default proj2D = tgt_mesh.Projection2D( f2opp ) proj2D.SourceFace( f2 ) # 3D hypotheses to project prisms from the source to the target mesh proj3D = tgt_mesh.Projection3D() proj3D.SourceShape3D( box, src_mesh, v1F1, v1F2, v2F1, v2F2 ) tgt_mesh.Compute() # Move the source mesh to visualy compare the two meshes src_mesh.TranslateObject( src_mesh, MakeDirStruct( 210, 0, 0 ), Copy=False) \endcode
\anchor tui_fixed_points

1D Mesh with Fixed Points example

\code import salome import geompy import smesh import StdMeshers # Create face and explode it on edges face = geompy.MakeFaceHW(100, 100, 1) edges = geompy.SubShapeAllSorted(face, geompy.ShapeType["EDGE"]) geompy.addToStudy( face, "Face" ) # get the first edge from exploded result edge1 = geompy.GetSubShapeID(face, edges[0]) # Define Mesh on previously created face Mesh_1 = smesh.Mesh(face) # Create Fixed Point 1D hypothesis and define parameters. # Note: values greater than 1.0 and less than 0.0 are not taken into account; # duplicated values are removed. Also, if not specified explicitly, values 0.0 and 1.0 # add added automatically. # The number of segments should correspond to the number of points (NbSeg = NbPnt-1); # extra values of segments splitting parameter are not taken into account, # while missing values are considered to be equal to 1. Fixed_points_1D_1 = smesh.CreateHypothesis('FixedPoints1D') Fixed_points_1D_1.SetPoints( [ 1.1, 0.9, 0.5, 0.0, 0.5, -0.3 ] ) Fixed_points_1D_1.SetNbSegments( [ 3, 1, 2 ] ) Fixed_points_1D_1.SetReversedEdges( [edge1] ) # Add hypothesis to mesh and define 2D parameters Mesh_1.AddHypothesis(Fixed_points_1D_1) Regular_1D = Mesh_1.Segment() Quadrangle_2D = Mesh_1.Quadrangle() # Compute mesh Mesh_1.Compute() \endcode \anchor tui_radial_quadrangle

Radial Quadrangle 1D2D example

\code from smesh import * SetCurrentStudy(salome.myStudy) # Create face from the wire and add to study Face = geompy.MakeSketcher("Sketcher:F 0 0:TT 20 0:R 90:C 20 90:WF", [0, 0, 0, 1, 0, 0, 0, 0, 1]) geompy.addToStudy(Face,"Face") edges = geompy.SubShapeAllSorted(Face, geompy.ShapeType["EDGE"]) circle, radius1, radius2 = edges geompy.addToStudyInFather(Face, radius1,"radius1") geompy.addToStudyInFather(Face, radius2,"radius2") geompy.addToStudyInFather(Face, circle,"circle") # Define geometry for mesh, and Radial Quadrange algorithm mesh = smesh.Mesh(Face) radial_Quad_algo = mesh.Quadrangle(algo=RADIAL_QUAD) # The Radial Quadrange algorithm can work without any hypothesis # In this case it uses "Default Nb of Segments" preferences parameter to discretize edges mesh.Compute() # The Radial Quadrange uses global or local 1d hypotheses if no its own hypotheses assigned. # Define global hypotheses to discretize radial edges and a local one for circular edge global_Nb_Segments = mesh.Segment().NumberOfSegments(5) local_Nb_Segments = mesh.Segment(circle).NumberOfSegments(10) mesh.Compute() # Define own parameters of Radial Quadrange algorithm radial_Quad_algo.NumberOfLayers( 4 ) mesh.Compute() \endcode \n Other meshing algorithms: */