Mesh_Algorithm Class Reference

The base class to define meshing algorithms. More...

Public Member Functions
def	__init__
	Private constuctor. More...
def	FindHypothesis
	Finds a hypothesis in the study by its type name and parameters. More...
def	FindAlgorithm
	Finds the algorithm in the study by its type name. More...
def	GetSubMesh
	If the algorithm is global, returns 0; else returns the submesh associated to this algorithm. More...
def	GetAlgorithm
	Returns the wrapped mesher. More...
def	GetCompatibleHypothesis
	Gets the list of hypothesis that can be used with this algorithm. More...
def	GetName
	Gets the name of the algorithm. More...
def	SetName
	Sets the name to the algorithm. More...
def	GetId
	Gets the id of the algorithm. More...
def	Create
	Private method. More...
def	Assign
	Private method. More...
def	CompareHyp
def	CompareEqualHyp
def	Hypothesis
	Private method. More...
def	MainShapeEntry
	Returns entry of the shape to mesh in the study. More...
def	ViscousLayers
	Defines "ViscousLayers" hypothesis to give parameters of layers of prisms to build near mesh boundary. More...
def	ViscousLayers2D
	Defines "ViscousLayers2D" hypothesis to give parameters of layers of quadrilateral elements to build near mesh boundary. More...
def	ReversedEdgeIndices
	Transform a list of either edges or tuples (edge, 1st_vertex_of_edge) into a list acceptable to SetReversedEdges() of some 1D hypotheses. More...

Data Fields
	mesh
	geom
	subm
	algo

Detailed Description

The base class to define meshing algorithms.

Note

This class should not be used directly, it is supposed to be sub-classed for implementing Python API for specific meshing algorithms

For each meshing algorithm, a python class inheriting from class Mesh_Algorithm should be defined. This descendant class should have two attributes defining the way it is created by class Mesh (see e.g. class StdMeshersBuilder_Segment in StdMeshersBuilder package):

• meshMethod attribute defines name of method of class smesh.Mesh by calling which the python class of algorithm is created; this method is dynamically added to the smesh.Mesh class in runtime. For example, if in class MyPlugin_Algorithm this attribute is defined as

  meshMethod = "MyAlgorithm"

  then an instance of MyPlugin_Algorithm can be created by the direct invocation of the function of smesh.Mesh class:

  my_algo = mesh.MyAlgorithm()

• algoType defines type of algorithm and is used mostly to discriminate algorithms that are created by the same method of class smesh.Mesh. For example, if this attribute is specified in MyPlugin_Algorithm class as

  algoType = "MyPLUGIN"

  then it's creation code can be:

  my_algo = mesh.MyAlgorithm(algo="MyPLUGIN")

Constructor & Destructor Documentation

def __init__

(

self

)

Private constuctor.

Member Function Documentation

def FindHypothesis	(		self,
			hypname,
			args,
			CompareMethod,
			smeshpyD
	)

Finds a hypothesis in the study by its type name and parameters.

Finds only the hypotheses created in smeshpyD engine.

Returns

SMESH.SMESH_Hypothesis

def FindAlgorithm	(		self,
			algoname,
			smeshpyD
	)

Finds the algorithm in the study by its type name.

Finds only the algorithms, which have been created in smeshpyD engine.

Returns

SMESH.SMESH_Algo

def GetSubMesh

(

self

)

If the algorithm is global, returns 0;
else returns the submesh associated to this algorithm.

References Mesh_Algorithm.subm.

def GetAlgorithm

(

self

)

Returns the wrapped mesher.

References Mesh_Algorithm.algo.

def GetCompatibleHypothesis

(

self

)

Gets the list of hypothesis that can be used with this algorithm.

References Mesh_Algorithm.algo.

def GetName

(

self

)

Gets the name of the algorithm.

References Mesh_Algorithm.algo.

def SetName	(		self,
			name
	)

Sets the name to the algorithm.

References Mesh_Algorithm.algo.

def GetId

(

self

)

Gets the id of the algorithm.

def Create	(		self,
			mesh,
			geom,
			hypo,
			so = "libStdMeshersEngine.so"
	)

Private method.

References Mesh_Algorithm.algo, Mesh_Algorithm.Assign(), and Mesh_Algorithm.FindAlgorithm().

def Assign	(		self,
			algo,
			mesh,
			geom
	)

Private method.

References Mesh_Algorithm.algo, Mesh_Algorithm.geom, Mesh_Algorithm.mesh, and Mesh_Algorithm.subm.

def CompareHyp	(		self,
			hyp,
			args
	)

def CompareEqualHyp	(		self,
			hyp,
			args
	)

References Mesh_Algorithm.Hypothesis().

def Hypothesis	(		self,
			hyp,
			args = [],
			so = "libStdMeshersEngine.so",
			UseExisting = 0,
			CompareMethod = "",
			toAdd = True
	)

Private method.

References Mesh_Algorithm.CompareHyp(), Mesh_Algorithm.FindHypothesis(), Mesh_Algorithm.geom, Mesh_Algorithm.GetName(), and Mesh_Algorithm.mesh.

def MainShapeEntry

(

self

)

Returns entry of the shape to mesh in the study.

References Mesh_Algorithm.mesh, and Mesh_Algorithm.ViscousLayers().

def ViscousLayers	(		self,
			thickness,
			numberOfLayers,
			stretchFactor,
			faces = [],
			isFacesToIgnore = True,
			extrMethod = StdMeshers.SURF_OFFSET_SMOOTH
	)

Defines "ViscousLayers" hypothesis to give parameters of layers of prisms to build near mesh boundary.

This hypothesis can be used by several 3D algorithms: NETGEN 3D, MG-Tetra, Hexahedron(i,j,k)

Parameters

thickness	total thickness of layers of prisms
numberOfLayers	number of layers of prisms
stretchFactor	factor (>1.0) of growth of layer thickness towards inside of mesh
faces	list of geometrical faces (or their ids). Viscous layers are either generated on these faces or not, depending on the value of isFacesToIgnore parameter.
isFacesToIgnore	if True, the Viscous layers are not generated on the faces specified by the previous parameter (faces).
extrMethod	extrusion method defines how position of new nodes are found during prism construction and how creation of distorted and intersecting prisms is prevented. Possible values are: StdMeshers.SURF_OFFSET_SMOOTH (default) method extrudes nodes along normal to underlying geometrical surface. Smoothing of internal surface of element layers can be used to avoid creation of invalid prisms. StdMeshers.FACE_OFFSET method extrudes nodes along average normal of surrounding mesh faces till intersection with a neighbor mesh face translated along its own normal by the layers thickness. Thickness of layers can be limited to avoid creation of invalid prisms. StdMeshers.NODE_OFFSET method extrudes nodes along average normal of surrounding mesh faces by the layers thickness. Thickness of layers can be limited to avoid creation of invalid prisms.

References Mesh_Algorithm.algo, Mesh_Algorithm.geom, Mesh_Algorithm.GetCompatibleHypothesis(), Mesh_Algorithm.Hypothesis(), and Mesh_Algorithm.ViscousLayers2D().

def ViscousLayers2D	(		self,
			thickness,
			numberOfLayers,
			stretchFactor,
			edges = [],
			isEdgesToIgnore = True
	)

Defines "ViscousLayers2D" hypothesis to give parameters of layers of quadrilateral elements to build near mesh boundary.

This hypothesis can be used by several 2D algorithms: NETGEN 2D, NETGEN 1D-2D, Quadrangle (mapping), MEFISTO, MG-CADSurf

Parameters

thickness	total thickness of layers of quadrilaterals
numberOfLayers	number of layers
stretchFactor	factor (>1.0) of growth of layer thickness towards inside of mesh
edges	list of geometrical edges (or their ids). Viscous layers are either generated on these edges or not, depending on the value of isEdgesToIgnore parameter.
isEdgesToIgnore	if True, the Viscous layers are not generated on the edges specified by the previous parameter (edges).

References Mesh_Algorithm.algo, Mesh_Algorithm.geom, Mesh_Algorithm.GetCompatibleHypothesis(), and Mesh_Algorithm.Hypothesis().

def ReversedEdgeIndices	(		self,
			reverseList
	)

Transform a list of either edges or tuples (edge, 1st_vertex_of_edge) into a list acceptable to SetReversedEdges() of some 1D hypotheses.

References Mesh_Algorithm.mesh.

Field Documentation

mesh

geom

subm

algo