artisynth.core.femmodels

Class ShellTriElement

java.lang.Object

artisynth.core.modelbase.ModelComponentBase

artisynth.core.modelbase.RenderableComponentBase

artisynth.core.femmodels.FemElement

artisynth.core.femmodels.FemElement3dBase

artisynth.core.femmodels.ShellElement3d

artisynth.core.femmodels.ShellTriElement

All Implemented Interfaces:

FrameAttachable, PointAttachable, CopyableComponent, HasNumericState, ModelComponent, PostScannable, PropertyChangeListener, RenderableComponent, ScalableUnits, java.lang.Cloneable, Boundable, HasProperties, HierarchyNode, HasRenderProps, IsRenderable, IsSelectable, Renderable, Scannable

public class ShellTriElement
extends ShellElement3d

Implementation of a triangle shell element with 3 shell nodes and 9 gauss points.

Nested Class Summary

Nested classes/interfaces inherited from class artisynth.core.femmodels.FemElement

FemElement.ElementClass

Nested classes/interfaces inherited from interface artisynth.core.modelbase.ModelComponent

ModelComponent.FilePathSaveType, ModelComponent.NavpanelVisibility

Field Summary

Fields

Modifier and Type	Field and Description
static double[]	INTEGRATION_COORDS_GAUSS_9
static double[]	INTEGRATION_COORDS_MEMBRANE

Fields inherited from class artisynth.core.femmodels.ShellElement3d

myProps

Fields inherited from class artisynth.core.femmodels.FemElement

setScannedNodesInPostscan, writeNodeRefsByNumber

Fields inherited from class artisynth.core.modelbase.ModelComponentBase

enforceUniqueCompositeNames, enforceUniqueNames, myNumber, NULL_OBJ, useCompactPathNames

Fields inherited from interface artisynth.core.modelbase.CopyableComponent

COPY_REFERENCES, REST_POSITION

Fields inherited from interface maspack.render.IsRenderable

TRANSPARENT, TWO_DIMENSIONAL

Constructor Summary

Constructors

Constructor and Description
ShellTriElement() End of variables and static blocks declarations
ShellTriElement(FemNode3d[] nodes, double thickness, boolean membrane) Creates a new triangle element from three nodes, arranged counter-clockwise around the elements outer facing normal.
ShellTriElement(FemNode3d p0, FemNode3d p1, FemNode3d p2, double thickness) Creates a new triangle element from three nodes, arranged counter-clockwise around the elements outer facing normal.
ShellTriElement(FemNode3d p0, FemNode3d p1, FemNode3d p2, double thickness, boolean membrane) Creates a new triangle element from three nodes, arranged counter-clockwise around the elements outer facing normal.

Method Summary

Modifier and Type	Method and Description
double	computeNodeNormal(Vector3d nrm, FemNode3d node) Computes the shell element normal, with respect to current coordinates, at a specific node, and returns the (cross product) area associated with that normal.
double	computeRestNodeNormal(Vector3d nrm, FemNode3d node) Computes the shell element normal, with respect to rest coordinates, at a specific node, and returns the (cross product) area associated with that normal.
boolean	coordsAreInside(Vector3d coords) Queries whether or not a set of natural coordinates are inside this element.
void	getdNds(Vector3d dNds, int n, Vector3d rst) Compute 1st derivative of shape function of particular node.
int[]	getEdgeIndices()
int[]	getFaceIndices()
double[]	getIntegrationCoords() Returns the natural coordinates and weights for the default integration points associated with this element.
IntegrationPoint3d[]	getIntegrationPoints() Returns the integration points associated with this element, not including the warping point (see FemElement3dBase.getWarpingPoint()).
int[]	getInverseNodeOrdering() Returns a node index reordering that inverts the element volume ( or flips its orientation for shell elements).
double	getN(int n, Vector3d rst) Compute shape function of particular node.
MatrixNd	getNodalAveragingMatrix() Returns the nodal averaging matrix for this element, used for extrapolating values from the integration points to the element nodes for purposes of computing average nodal values.
MatrixNd	getNodalExtrapolationMatrix() Returns the nodal extrapolation matrix for this element.
double[]	getNodeCoords()
double[]	getNodeMassWeights()
int[]	getTriangulatedFaceIndices()
IntegrationPoint3d	getWarpingPoint() Returns the special warping integration point which is located at the center of the element and is used for computing stiffness warping and other specialized applications.
double	nearestPoint(Point3d near, Point3d pnt)
int	numIntegrationPoints() Returns the number of integration points actually used by this element (not including the warping point, if any).
int	numPlanarIntegrationPoints() Number of integration points in the shell plane.
void	render(Renderer renderer, RenderProps props, int flags)
void	renderWidget(Renderer renderer, double size, RenderProps props)
void	setNodes(FemNode3d p0, FemNode3d p1, FemNode3d p2)

Methods inherited from class artisynth.core.femmodels.ShellElement3d

computeJacobian, computeLocalPosition, computeRestVolumes, computeVolumes, connectToHierarchy, copy, createElement, disconnectFromHierarchy, doComputeVolume, getAllPropertyInfo, getDefaultThickness, invalidateRestData, setDefaultThickness

Methods inherited from class artisynth.core.femmodels.FemElement3dBase

addConsistentGravity, addConsistentMass, advanceState, clearRotationData, computeConsistentMass, computeCovariance, computeDirectedRenderSize, computeGravityWeights, computeRenderCoordsAndGradient, containsEdge, containsFace, containsFace, containsNode, createFrameAttachment, createIntegrationPoints, createPointAttachment, getAllIntegrationPoints, getCopyReferences, getDeformation, getDeformation, getElementClass, getElementWidgetSize, getElementWidgetSizeMode, getFaces, getFemModel, getFrame, getIntegrationData, getIntegrationShapeMatrix, getInvB, getInvB, getMarkerCoordinates, getNaturalCoordinates, getNaturalCoordinates, getNaturalCoordinatesGSS, getNodeCoords, getNodeNeighbors, getNodes, getNumFaces, getRotation, getRotation, getState, getStiffnessWarper, getWarpingData, invalidateRotationData, isInside, isInvertedAtRest, notifyStateVersionChanged, numAllIntegrationPoints, requiresAdvance, setElementWidgetSize, setElementWidgetSizeMode, setFrame, setNodes, setState, setStiffnessWarper, triangulateFace

Methods inherited from class artisynth.core.femmodels.FemElement

addAugmentingMaterial, addAuxiliaryMaterial, computeCentroid, containsNode, createRenderProps, defaultRenderPropsAreNull, getAugmentingMaterials, getAuxiliaryMaterials, getDensity, getDensityMode, getEffectiveMaterial, getHardReferences, getIndex, getLocalNodeIndex, getMass, getMaterial, getPlasticDeformation, getPoint, getRestVolume, getSelection, getStateVersion, getStrainEnergy, getVolume, hasActiveNodes, hasControllableNodes, hasState, integrationPointsInterpolateToNodes, integrationPointsMapToNodes, invalidateMassIfNecessary, isDuplicatable, isInverted, isLinear, isMassExplicit, materialsAreInvertible, numAugmentingMaterials, numAuxiliaryMaterials, numberString, numNodes, numPoints, prerender, propertyChanged, removeAugmentingMaterial, removeAuxiliaryMaterial, render, scaleDistance, scaleMass, setDensity, setDensityMode, setExplicitMass, setIndex, setInverted, setMass, setMaterial, setPlasticDeformation, unsetExplicitMass, updateBounds, updateRestVolumeAndMass

Methods inherited from class artisynth.core.modelbase.RenderableComponentBase

getRenderHints, getRenderProps, isSelectable, isVisible, numSelectionQueriesNeeded, setRenderProps, setVisible, updateRenderProps

Methods inherited from class artisynth.core.modelbase.ModelComponentBase

checkFlag, checkName, checkNameUniqueness, clearFlag, clone, createTempFlag, getChildren, getGrandParent, getName, getNameRange, getNavpanelVisibility, getNavpanelVisibility, getNumber, getParent, getProperty, getSoftReferences, hasChildren, isFixed, isMarked, isScanning, isSelected, isWritable, makeValidName, makeValidName, notifyParentOfChange, postscan, printReferences, recursivelyContained, recursivelyContains, removeTempFlag, scan, setFixed, setFlag, setMarked, setName, setNavpanelVisibility, setNavpanelVisibility, setNumber, setParent, setScanning, setSelected, setWritable, updateReferences, write

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface maspack.geometry.Boundable

computeCentroid, computeCovariance, getPoint, numPoints, updateBounds

Methods inherited from interface artisynth.core.mechmodels.FrameAttachable

createFrameAttachment

Methods inherited from interface artisynth.core.mechmodels.PointAttachable

createPointAttachment

Methods inherited from interface artisynth.core.modelbase.ModelComponent

getHardReferences, getName, getNavpanelVisibility, getNumber, getParent, getSoftReferences, hasState, isFixed, isMarked, isSelected, notifyParentOfChange, scan, setFixed, setMarked, setName, setNumber, setParent, setSelected, setWritable, updateReferences

Methods inherited from interface maspack.properties.HasProperties

getProperty

Methods inherited from interface maspack.properties.HierarchyNode

getChildren, hasChildren

Methods inherited from interface artisynth.core.modelbase.PostScannable

postscan

Methods inherited from interface maspack.util.Scannable

isWritable, write

Methods inherited from interface artisynth.core.modelbase.HasNumericState

getAuxVarDerivative, getAuxVarState, numAuxVars, setAuxVarState

Field Detail

INTEGRATION_COORDS_GAUSS_9

public static final double[] INTEGRATION_COORDS_GAUSS_9

INTEGRATION_COORDS_MEMBRANE

public static final double[] INTEGRATION_COORDS_MEMBRANE

Constructor Detail

ShellTriElement

public ShellTriElement()

End of variables and static blocks declarations

ShellTriElement

public ShellTriElement(FemNode3d p0,
                       FemNode3d p1,
                       FemNode3d p2,
                       double thickness)

Creates a new triangle element from three nodes, arranged counter-clockwise around the elements outer facing normal.

ShellTriElement

public ShellTriElement(FemNode3d p0,
                       FemNode3d p1,
                       FemNode3d p2,
                       double thickness,
                       boolean membrane)

Creates a new triangle element from three nodes, arranged counter-clockwise around the elements outer facing normal.

ShellTriElement

public ShellTriElement(FemNode3d[] nodes,
                       double thickness,
                       boolean membrane)

Creates a new triangle element from three nodes, arranged counter-clockwise around the elements outer facing normal.

Method Detail

setNodes

public void setNodes(FemNode3d p0,
                     FemNode3d p1,
                     FemNode3d p2)

getN

public double getN(int n,
                   Vector3d rst)

Compute shape function of particular node.

Specified by:

getN in class FemElement3dBase

Parameters:

n - Node index

rst - Integration point (i.e. Gauss point)

getdNds

public void getdNds(Vector3d dNds,
                    int n,
                    Vector3d rst)

Compute 1st derivative of shape function of particular node.

Specified by:

getdNds in class FemElement3dBase

getNodeCoords

public double[] getNodeCoords()

Specified by:

getNodeCoords in class FemElement3dBase

getNodeMassWeights

public double[] getNodeMassWeights()

Specified by:

getNodeMassWeights in class FemElement3dBase

getInverseNodeOrdering

public int[] getInverseNodeOrdering()

Description copied from class: FemElement3dBase

Returns a node index reordering that inverts the element volume ( or flips its orientation for shell elements). If for some reason such an ordering is unavailable, the method should return null.

Specified by:

getInverseNodeOrdering in class FemElement3dBase

getEdgeIndices

public int[] getEdgeIndices()

Specified by:

getEdgeIndices in class FemElement3dBase

getFaceIndices

public int[] getFaceIndices()

Specified by:

getFaceIndices in class FemElement3dBase

getTriangulatedFaceIndices

public int[] getTriangulatedFaceIndices()

Specified by:

getTriangulatedFaceIndices in class FemElement3dBase

getIntegrationCoords

public double[] getIntegrationCoords()

Description copied from class: FemElement3dBase

Returns the natural coordinates and weights for the default integration points associated with this element. The information is returned as an array of length 4*num, where num is the number of coordinates, and the information for each coordinate consists of a 4-tuple giving the three natural coordinates followed by the weight.

Specified by:

getIntegrationCoords in class FemElement3dBase

Returns:

coordinates and weights for the default integration points.

numIntegrationPoints

public int numIntegrationPoints()

Description copied from class: FemElement3dBase

Returns the number of integration points actually used by this element (not including the warping point, if any). Typically this number will equal the length of the integration point array returned by FemElement3dBase.getIntegrationPoints(), but in some cases (such as shell elements being used as membrane elements), it will be less.

Specified by:

numIntegrationPoints in class FemElement3dBase

Returns:

number of integration points used by this element

getIntegrationPoints

public IntegrationPoint3d[] getIntegrationPoints()

Description copied from class: FemElement3dBase

Returns the integration points associated with this element, not including the warping point (see FemElement3dBase.getWarpingPoint()). In some cases, such as with membrane elements, only the first n points of these points are actaully used, where n is the number returned by FemElement3dBase.numIntegrationPoints().

Specified by:

getIntegrationPoints in class FemElement3dBase

numPlanarIntegrationPoints

public int numPlanarIntegrationPoints()

Description copied from class: ShellElement3d

Number of integration points in the shell plane.

Specified by:

numPlanarIntegrationPoints in class ShellElement3d

getWarpingPoint

public IntegrationPoint3d getWarpingPoint()

Description copied from class: FemElement3dBase

Returns the special warping integration point which is located at the center of the element and is used for computing stiffness warping and other specialized applications.

Specified by:

getWarpingPoint in class FemElement3dBase

coordsAreInside

public boolean coordsAreInside(Vector3d coords)

Description copied from class: FemElement3dBase

Queries whether or not a set of natural coordinates are inside this element.

Specified by:

coordsAreInside in class FemElement3dBase

Returns:

true if ncoords are inside this element.

getNodalAveragingMatrix

public MatrixNd getNodalAveragingMatrix()

Description copied from class: FemElement3dBase

Returns the nodal averaging matrix for this element, used for extrapolating values from the integration points to the element nodes for purposes of computing average nodal values. By default, this matrix is the same as that returned by FemElement3dBase.getNodalExtrapolationMatrix(). However, since the purpose of this matrix is for computing nodal averages, simpler matrices can sometimes be used, such as an identity or permutation matrix that assigns the value at each node to that of a specific integration point. Element subclasses may override this method to supply such simplified matrices.

Overrides:

getNodalAveragingMatrix in class FemElement3dBase

Returns:

nodal extrapolation matrix

getNodalExtrapolationMatrix

public MatrixNd getNodalExtrapolationMatrix()

Description copied from class: FemElement3dBase

Returns the nodal extrapolation matrix for this element. This is a matrix that maps values from the integration points to the element nodes, and is the inverse (or pseudo-inverse) of the integration point shape matrix returned by FemElement3dBase.getIntegrationShapeMatrix().

Specified by:

getNodalExtrapolationMatrix in class FemElement3dBase

Returns:

nodal extrapolation matrix

nearestPoint

public double nearestPoint(Point3d near,
                           Point3d pnt)

Specified by:

nearestPoint in class ShellElement3d

computeRestNodeNormal

public double computeRestNodeNormal(Vector3d nrm,
                                    FemNode3d node)

Description copied from class: ShellElement3d

Computes the shell element normal, with respect to rest coordinates, at a specific node, and returns the (cross product) area associated with that normal. This is used for automatically initializing directors.

Specified by:

computeRestNodeNormal in class ShellElement3d

computeNodeNormal

public double computeNodeNormal(Vector3d nrm,
                                FemNode3d node)

Description copied from class: ShellElement3d

Computes the shell element normal, with respect to current coordinates, at a specific node, and returns the (cross product) area associated with that normal. This can be used for automatically initializing directors.

Specified by:

computeNodeNormal in class ShellElement3d

render

public void render(Renderer renderer,
                   RenderProps props,
                   int flags)

Specified by:

render in class FemElement

renderWidget

public void renderWidget(Renderer renderer,
                         double size,
                         RenderProps props)

Specified by:

renderWidget in class FemElement3dBase