MeshGmshLoader

This component belongs to the category of the MeshLoaders.

The MeshGmshLoader loads a mesh from a file under the format *.msh. Such a mesh file can be either surface or volumetric meshes. The *.msh meshes can be generated using software like Gmsh. To be noted, an interesting project couples SOFA and Gmsh in python for applications such as parametric design or design optimization.

Usage

No pre-requisite in your scene to use a MeshLoader.

Specific mesh loader for Gmsh file format.

Target: Sofa.Component.IO.Mesh

namespace: sofa::component::io::mesh

parents:

• MeshLoader

Data

Name	Description	Default value
name	object name	unnamed
printLog	if true, emits extra messages at runtime.	0
tags	list of the subsets the objet belongs to
bbox	this object bounding box
componentState	The state of the component among (Dirty, Valid, Undefined, Loading, Invalid).	Undefined
listening	if true, handle the events, otherwise ignore the events	0
filename	Filename of the object
flipNormals	Flip Normals	0
triangulate	Divide all polygons into triangles	0
createSubelements	Divide all n-D elements into their (n-1)-D boundary elements (e.g. tetrahedra to triangles)	0
onlyAttachedPoints	Only keep points attached to elements of the mesh	0
translation	Translation of the DOFs	0 0 0
rotation	Rotation of the DOFs	0 0 0
scale3d	Scale of the DOFs in 3 dimensions	1 1 1
transformation	4x4 Homogeneous matrix to transform the DOFs (when present replace any)	[1 0 0 0,0 1 0 0,0 0 1 0,0 0 0 1]
Vectors
position	Vertices of the mesh loaded
polylines	Polylines of the mesh loaded
edges	Edges of the mesh loaded
triangles	Triangles of the mesh loaded
quads	Quads of the mesh loaded
polygons	Polygons of the mesh loaded
highOrderEdgePositions	High order edge points of the mesh loaded
highOrderTrianglePositions	High order triangle points of the mesh loaded
highOrderQuadPositions	High order quad points of the mesh loaded
tetrahedra	Tetrahedra of the mesh loaded
hexahedra	Hexahedra of the mesh loaded
pentahedra	Pentahedra of the mesh loaded
highOrderTetrahedronPositions	High order tetrahedron points of the mesh loaded
highOrderHexahedronPositions	High order hexahedron points of the mesh loaded
pyramids	Pyramids of the mesh loaded
normals	Normals of the mesh loaded
Groups
edgesGroups	Groups of Edges
trianglesGroups	Groups of Triangles
quadsGroups	Groups of Quads
polygonsGroups	Groups of Polygons
tetrahedraGroups	Groups of Tetrahedra
hexahedraGroups	Groups of Hexahedra
pentahedraGroups	Groups of Pentahedra
pyramidsGroups	Groups of Pyramids

Links

Name	Description	Destination type name
context	Graph Node containing this object (or BaseContext::getDefault() if no graph is used)	BaseContext
slaves	Sub-objects used internally by this object	BaseObject
master	nullptr for regular objects, or master object for which this object is one sub-objects	BaseObject

Examples

MeshGmshLoader.scn

XMLPython

<?xml version="1.0" ?>
<!-- For more details see: https://wiki.sofa-framework.org/tdev/wiki/Notes/NewLoaderArchitecture -->
<Node name="Root" gravity="0 -9.81 0" dt="0.05">
    <RequiredPlugin name="Sofa.Component.Collision.Detection.Algorithm"/> <!-- Needed to use components [BVHNarrowPhase BruteForceBroadPhase CollisionPipeline] -->
    <RequiredPlugin name="Sofa.Component.Collision.Detection.Intersection"/> <!-- Needed to use components [MinProximityIntersection] -->
    <RequiredPlugin name="Sofa.Component.Collision.Geometry"/> <!-- Needed to use components [TriangleCollisionModel] -->
    <RequiredPlugin name="Sofa.Component.Collision.Response.Contact"/> <!-- Needed to use components [CollisionResponse] -->
    <RequiredPlugin name="Sofa.Component.Constraint.Projective"/> <!-- Needed to use components [FixedProjectiveConstraint] -->
    <RequiredPlugin name="Sofa.Component.IO.Mesh"/> <!-- Needed to use components [MeshGmshLoader] -->
    <RequiredPlugin name="Sofa.Component.LinearSolver.Iterative"/> <!-- Needed to use components [CGLinearSolver] -->
    <RequiredPlugin name="Sofa.Component.Mapping.Linear"/> <!-- Needed to use components [IdentityMapping] -->
    <RequiredPlugin name="Sofa.Component.Mass"/> <!-- Needed to use components [DiagonalMass] -->
    <RequiredPlugin name="Sofa.Component.ODESolver.Backward"/> <!-- Needed to use components [EulerImplicitSolver] -->
    <RequiredPlugin name="Sofa.Component.SolidMechanics.FEM.Elastic"/> <!-- Needed to use components [TetrahedronFEMForceField TriangularFEMForceField] -->
    <RequiredPlugin name="Sofa.Component.SolidMechanics.Spring"/> <!-- Needed to use components [TriangularBendingSprings] -->
    <RequiredPlugin name="Sofa.Component.StateContainer"/> <!-- Needed to use components [MechanicalObject] -->
    <RequiredPlugin name="Sofa.Component.Topology.Container.Dynamic"/> <!-- Needed to use components [TetrahedronSetGeometryAlgorithms TetrahedronSetTopologyContainer TetrahedronSetTopologyModifier TriangleSetGeometryAlgorithms TriangleSetTopologyContainer TriangleSetTopologyModifier] -->
    <RequiredPlugin name="Sofa.Component.Visual"/> <!-- Needed to use components [VisualStyle] -->
    <RequiredPlugin name="Sofa.GL.Component.Rendering3D"/> <!-- Needed to use components [OglModel] -->

    <DefaultAnimationLoop/>
    <VisualStyle displayFlags="showVisual showBehaviorModels showForceFields showCollision showMapping" />
    <CollisionPipeline name="DefaultCollisionPipeline" verbose="0" draw="0" depth="6" />
    <BruteForceBroadPhase/>
    <BVHNarrowPhase/>
    <MinProximityIntersection name="Proximity" alarmDistance="0.3" contactDistance="0.2" />
    <CollisionResponse name="Response" response="PenalityContactForceField" />
    <Node name="gmsh file">
        <EulerImplicitSolver name="cg_odesolver" printLog="false"  rayleighStiffness="0.1" rayleighMass="0.1" />
        <CGLinearSolver iterations="25" name="linear solver" tolerance="1.0e-9" threshold="1.0e-9" />
        <MeshGmshLoader name="GmshLoader" filename="mesh/square3.msh" createSubelements="true" flipNormals="0" />
        <MechanicalObject name="dofs" scale="10" src="@GmshLoader" />
        <TriangleSetTopologyContainer name="topo" src="@GmshLoader" />
        <TriangleSetTopologyModifier name="modif" />
        <TriangleSetGeometryAlgorithms name="triGeo" drawEdges="1" />
        <DiagonalMass massDensity="0.15" />
        <FixedProjectiveConstraint indices="0 1" />
        <TriangularFEMForceField name="FEM" youngModulus="100" poissonRatio="0.3" method="large" />
        <TriangularBendingSprings name="FEM-Bend" stiffness="300" damping="1.0" />
        <TriangleCollisionModel />
        <Node>
            <OglModel src="@../GmshLoader" name="VisualModel" color="blue" />
            <IdentityMapping name="mapping" input="@.." output="@VisualModel" />
        </Node>
    </Node>
    <Node name="gmsh file v4">
        <EulerImplicitSolver name="cg_odesolver" printLog="false"  rayleighStiffness="0.1" rayleighMass="0.1" />
        <CGLinearSolver iterations="25" name="linear solver" tolerance="1.0e-9" threshold="1.0e-9" />
        <MeshGmshLoader name="GmshLoaderv4" filename="mesh/msh4_cube.msh" createSubelements="true" flipNormals="0" />
        <MechanicalObject name="dofs" scale="10" src="@GmshLoaderv4" />
        <TetrahedronSetTopologyContainer name="topo" src="@GmshLoaderv4" />
        <TetrahedronSetTopologyModifier name="modif" />
        <TetrahedronSetGeometryAlgorithms template="Vec3" name="tetraGeo" />
        <DiagonalMass massDensity="0.2" />
        <FixedProjectiveConstraint indices="0 1" />
        <TetrahedronFEMForceField name="FEM" youngModulus="1000" poissonRatio="0.3" method="large" />
        <TriangleCollisionModel />
        <Node>
            <OglModel src="@../GmshLoaderv4" name="VisualModel" color="blue" />
            <IdentityMapping name="mapping" input="@.." output="@VisualModel" />
        </Node>
    </Node>
</Node>

def createScene(root_node):

   root = root_node.addChild('Root', gravity="0 -9.81 0", dt="0.05")

   root.addObject('RequiredPlugin', name="Sofa.Component.Collision.Detection.Algorithm")
   root.addObject('RequiredPlugin', name="Sofa.Component.Collision.Detection.Intersection")
   root.addObject('RequiredPlugin', name="Sofa.Component.Collision.Geometry")
   root.addObject('RequiredPlugin', name="Sofa.Component.Collision.Response.Contact")
   root.addObject('RequiredPlugin', name="Sofa.Component.Constraint.Projective")
   root.addObject('RequiredPlugin', name="Sofa.Component.IO.Mesh")
   root.addObject('RequiredPlugin', name="Sofa.Component.LinearSolver.Iterative")
   root.addObject('RequiredPlugin', name="Sofa.Component.Mapping.Linear")
   root.addObject('RequiredPlugin', name="Sofa.Component.Mass")
   root.addObject('RequiredPlugin', name="Sofa.Component.ODESolver.Backward")
   root.addObject('RequiredPlugin', name="Sofa.Component.SolidMechanics.FEM.Elastic")
   root.addObject('RequiredPlugin', name="Sofa.Component.SolidMechanics.Spring")
   root.addObject('RequiredPlugin', name="Sofa.Component.StateContainer")
   root.addObject('RequiredPlugin', name="Sofa.Component.Topology.Container.Dynamic")
   root.addObject('RequiredPlugin', name="Sofa.Component.Visual")
   root.addObject('RequiredPlugin', name="Sofa.GL.Component.Rendering3D")
   root.addObject('DefaultAnimationLoop', )
   root.addObject('VisualStyle', displayFlags="showVisual showBehaviorModels showForceFields showCollision showMapping")
   root.addObject('CollisionPipeline', name="DefaultCollisionPipeline", verbose="0", draw="0", depth="6")
   root.addObject('BruteForceBroadPhase', )
   root.addObject('BVHNarrowPhase', )
   root.addObject('MinProximityIntersection', name="Proximity", alarmDistance="0.3", contactDistance="0.2")
   root.addObject('CollisionResponse', name="Response", response="PenalityContactForceField")

   gmsh_file = Root.addChild('gmsh file')

   gmsh_file.addObject('EulerImplicitSolver', name="cg_odesolver", printLog="false", rayleighStiffness="0.1", rayleighMass="0.1")
   gmsh_file.addObject('CGLinearSolver', iterations="25", name="linear solver", tolerance="1.0e-9", threshold="1.0e-9")
   gmsh_file.addObject('MeshGmshLoader', name="GmshLoader", filename="mesh/square3.msh", createSubelements="true", flipNormals="0")
   gmsh_file.addObject('MechanicalObject', name="dofs", scale="10", src="@GmshLoader")
   gmsh_file.addObject('TriangleSetTopologyContainer', name="topo", src="@GmshLoader")
   gmsh_file.addObject('TriangleSetTopologyModifier', name="modif")
   gmsh_file.addObject('TriangleSetGeometryAlgorithms', name="triGeo", drawEdges="1")
   gmsh_file.addObject('DiagonalMass', massDensity="0.15")
   gmsh_file.addObject('FixedProjectiveConstraint', indices="0 1")
   gmsh_file.addObject('TriangularFEMForceField', name="FEM", youngModulus="100", poissonRatio="0.3", method="large")
   gmsh_file.addObject('TriangularBendingSprings', name="FEM-Bend", stiffness="300", damping="1.0")
   gmsh_file.addObject('TriangleCollisionModel', )

   node = gmsh file.addChild('node')

   node.addObject('OglModel', src="@../GmshLoader", name="VisualModel", color="blue")
   node.addObject('IdentityMapping', name="mapping", input="@..", output="@VisualModel")

   gmsh_file_v4 = Root.addChild('gmsh file v4')

   gmsh_file_v4.addObject('EulerImplicitSolver', name="cg_odesolver", printLog="false", rayleighStiffness="0.1", rayleighMass="0.1")
   gmsh_file_v4.addObject('CGLinearSolver', iterations="25", name="linear solver", tolerance="1.0e-9", threshold="1.0e-9")
   gmsh_file_v4.addObject('MeshGmshLoader', name="GmshLoaderv4", filename="mesh/msh4_cube.msh", createSubelements="true", flipNormals="0")
   gmsh_file_v4.addObject('MechanicalObject', name="dofs", scale="10", src="@GmshLoaderv4")
   gmsh_file_v4.addObject('TetrahedronSetTopologyContainer', name="topo", src="@GmshLoaderv4")
   gmsh_file_v4.addObject('TetrahedronSetTopologyModifier', name="modif")
   gmsh_file_v4.addObject('TetrahedronSetGeometryAlgorithms', template="Vec3", name="tetraGeo")
   gmsh_file_v4.addObject('DiagonalMass', massDensity="0.2")
   gmsh_file_v4.addObject('FixedProjectiveConstraint', indices="0 1")
   gmsh_file_v4.addObject('TetrahedronFEMForceField', name="FEM", youngModulus="1000", poissonRatio="0.3", method="large")
   gmsh_file_v4.addObject('TriangleCollisionModel', )

   node = gmsh file v4.addChild('node')

   node.addObject('OglModel', src="@../GmshLoaderv4", name="VisualModel", color="blue")
   node.addObject('IdentityMapping', name="mapping", input="@..", output="@VisualModel")