artisynth.core.mechmodels
Class AxialSpring

java.lang.Object
  extended by artisynth.core.modelbase.ModelComponentBase
      extended by artisynth.core.mechmodels.Spring
          extended by artisynth.core.mechmodels.PointSpringBase
              extended by artisynth.core.mechmodels.AxialSpring
All Implemented Interfaces:
ForceComponent, ForceEffector, CopyableComponent, ModelComponent, RenderableComponent, ScalableUnits, java.lang.Cloneable, HasProperties, HierarchyNode, GLRenderable, GLSelectable, HasRenderProps, Renderable, RenderableLine, Scannable
Direct Known Subclasses:
Muscle

public class AxialSpring
extends PointSpringBase
implements RenderableLine, ScalableUnits, CopyableComponent


Nested Class Summary
 
Nested classes/interfaces inherited from interface artisynth.core.modelbase.ModelComponent
ModelComponent.NavpanelVisibility
 
Field Summary
static PropertyList myProps
           
 
Fields inherited from class artisynth.core.mechmodels.PointSpringBase
myIgnoreCoriolisInJacobian, useMaterial
 
Fields inherited from class artisynth.core.modelbase.ModelComponentBase
enforceUniqueCompositeNames, enforceUniqueNames, myNumber, NULL_OBJ, useCompactPathNames
 
Fields inherited from interface maspack.render.GLRenderable
TRANSLUCENT, TWO_DIMENSIONAL
 
Fields inherited from interface artisynth.core.modelbase.CopyableComponent
COPY_REFERENCES
 
Constructor Summary
AxialSpring()
           
AxialSpring(double k, double d, double l)
           
AxialSpring(java.lang.String name)
           
AxialSpring(java.lang.String name, double k, double d, double l)
           
 
Method Summary
 void addPosJacobian(SparseNumberedBlockMatrix M, double s)
          Scales the components of the position Jacobian associated with this force effector and adds it to the supplied solve matrix M.
 void addSolveBlocks(SparseNumberedBlockMatrix M)
          Adds any needed blocks to a solve matrix in order to accomodate the Jacobian terms associated with this force effector.
 void addVelJacobian(SparseNumberedBlockMatrix M, double s)
          Scales the components of the velocity Jacobian associated with this force effector and adds it to the supplied solve matrix M.
 void applyForces(double t)
          Adds forces to the components affected by this force effector at a particular time.
 void computeForce(Vector3d f)
          Computes the force acting on the first point.
 void computeForcePositionJacobian(Matrix3d M)
          Computes the force/position Jacobian of this spring.
 void computeForceVelocityJacobian(Matrix3d M)
          Computes the force/velocity Jacobian of this spring.
 ModelComponent copy(int flags, java.util.Map<ModelComponent,ModelComponent> copyMap)
          Create a copy of this component.
 PropertyList getAllPropertyInfo()
          Returns a list giving static information about all properties exported by this object.
 boolean getCopyReferences(java.util.List<ModelComponent> refs, ModelComponent ancestor)
          Collects external references which must also be copied in order to duplicate this component.
 Vector3d getDir()
           
 Point getFirstPoint()
           
 void getHardReferences(java.util.List<ModelComponent> refs)
          Appends all hard references for this component to a list.
 int getJacobianType()
          Returns a code indicating the matrix type that results when the Jacobian terms of this force effector are added to the solve matrix.
 double getLength()
           
 double getLengthDot()
           
 float[] getRenderCoords0()
           
 float[] getRenderCoords1()
           
 Point getSecondPoint()
           
 boolean isDuplicatable()
          Returns true if this component can be duplicated.
 void printPointReferences(java.io.PrintWriter pw, CompositeComponent ancestor)
           
 void render(GLRenderer renderer, int flags)
          Render this object using Open GL via the JOGL.
 void scaleDistance(double s)
          Scales all distance coordinates.
 void scaleMass(double s)
          Scales all mass units.
 void setFirstPoint(Point pnt)
           
 void setPoints(Point p1, Point p2)
           
 void setPoints(Point p1, Point p2, double restLength)
           
 double setRestLengthFromPoints()
          Sets the rest length of the spring from the current point locations
 void setSecondPoint(Point pnt)
           
 void updateBounds(Point3d pmin, Point3d pmax)
          Update the minimum and maximum points for this object.
 void write(java.io.PrintWriter pw, NumberFormat fmt, java.lang.Object ref)
          Writes a text description of this element to a PrintWriter.
 
Methods inherited from class artisynth.core.mechmodels.PointSpringBase
computeDFdl, computeDFdldot, computeF, createDefaultMaterial, createRenderProps, getEffectiveMaterial, getMaterial, getMaxForce, getRenderColor, getRenderHints, getRenderProps, getRestLength, getSelection, isSelectable, numSelectionQueriesNeeded, prerender, setDamping, setLinearMaterial, setMaterial, setMaxForce, setRenderProps, setRestLength, setStiffness
 
Methods inherited from class artisynth.core.modelbase.ModelComponentBase
checkFlag, checkName, checkNameUniqueness, clearFlag, clone, connectToHierarchy, createTempFlag, disconnectFromHierarchy, getChildren, getGrandParent, getName, getNameRange, getNavpanelVisibility, getNavpanelVisibility, getNumber, getParent, getProperty, getSoftReferences, hasChildren, hasState, isFixed, isMarked, isSelected, isWritable, makeValidName, makeValidName, notifyParentOfChange, postscan, printReferences, recursivelyContained, recursivelyContains, removeTempFlag, scan, setFixed, setFlag, setMarked, setName, setNavpanelVisibility, setNavpanelVisibility, setNumber, setParent, setSelected, updateReferences
 
Methods inherited from class java.lang.Object
equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 
Methods inherited from interface maspack.render.RenderableLine
getRenderColor, isSelected
 
Methods inherited from interface maspack.render.GLSelectable
getSelection, isSelectable, numSelectionQueriesNeeded
 
Methods inherited from interface maspack.render.GLRenderable
getRenderHints, prerender
 
Methods inherited from interface maspack.render.HasRenderProps
createRenderProps, getRenderProps, setRenderProps
 
Methods inherited from interface artisynth.core.modelbase.ModelComponent
connectToHierarchy, disconnectFromHierarchy, getName, getNavpanelVisibility, getNumber, getParent, getSoftReferences, hasState, isFixed, isMarked, isSelected, notifyParentOfChange, postscan, scan, setFixed, setMarked, setName, setNumber, setParent, setSelected, updateReferences
 
Methods inherited from interface maspack.properties.HasProperties
getProperty
 
Methods inherited from interface maspack.properties.HierarchyNode
getChildren, hasChildren
 
Methods inherited from interface maspack.util.Scannable
isWritable
 

Field Detail

myProps

public static PropertyList myProps
Constructor Detail

AxialSpring

public AxialSpring()

AxialSpring

public AxialSpring(java.lang.String name)

AxialSpring

public AxialSpring(java.lang.String name,
                   double k,
                   double d,
                   double l)

AxialSpring

public AxialSpring(double k,
                   double d,
                   double l)
Method Detail

getAllPropertyInfo

public PropertyList getAllPropertyInfo()
Description copied from interface: HasProperties
Returns a list giving static information about all properties exported by this object.

Specified by:
getAllPropertyInfo in interface HasProperties
Overrides:
getAllPropertyInfo in class PointSpringBase
Returns:
static information for all exported properties

getFirstPoint

public Point getFirstPoint()

getSecondPoint

public Point getSecondPoint()

setPoints

public void setPoints(Point p1,
                      Point p2)

setPoints

public void setPoints(Point p1,
                      Point p2,
                      double restLength)

setFirstPoint

public void setFirstPoint(Point pnt)

setSecondPoint

public void setSecondPoint(Point pnt)

setRestLengthFromPoints

public double setRestLengthFromPoints()
Description copied from class: PointSpringBase
Sets the rest length of the spring from the current point locations

Specified by:
setRestLengthFromPoints in class PointSpringBase
Returns:
the new rest length

computeForce

public void computeForce(Vector3d f)
Computes the force acting on the first point. The force acting on the second point is the negative of this force.

Parameters:
f - returns the computed force acting on the first point

applyForces

public void applyForces(double t)
Description copied from interface: ForceEffector
Adds forces to the components affected by this force effector at a particular time. Component forces should be added and not set, since other forces may be added to the same components by other force effectors.

Specified by:
applyForces in interface ForceEffector
Specified by:
applyForces in class Spring
Parameters:
t - time (seconds)

printPointReferences

public void printPointReferences(java.io.PrintWriter pw,
                                 CompositeComponent ancestor)
                          throws java.io.IOException
Throws:
java.io.IOException

write

public void write(java.io.PrintWriter pw,
                  NumberFormat fmt,
                  java.lang.Object ref)
           throws java.io.IOException
Description copied from class: ModelComponentBase
Writes a text description of this element to a PrintWriter. The text description should be compatable with scan and complete enough to allow full reconstruction of the element.

Specified by:
write in interface Scannable
Overrides:
write in class ModelComponentBase
Parameters:
pw - stream for writing the element
fmt - numeric formating information
ref - optional reference object which can be used for producing references to other objects
Throws:
java.io.IOException - if an I/O error occured

getRenderCoords0

public float[] getRenderCoords0()
Specified by:
getRenderCoords0 in interface RenderableLine

getRenderCoords1

public float[] getRenderCoords1()
Specified by:
getRenderCoords1 in interface RenderableLine

updateBounds

public void updateBounds(Point3d pmin,
                         Point3d pmax)
Description copied from interface: GLRenderable
Update the minimum and maximum points for this object. In an x-y-z coordinate system with x directed to the right and y directed upwards, the minimum and maximum points can be thought of as defining the left-lower-far and right-upper-near corners of a bounding cube. This method should only reduce the elements of the minimum point and increase the elements of the maximum point, since it may be used as part of an iteration to determine the bounding cube for several different objects.

Specified by:
updateBounds in interface GLRenderable
Specified by:
updateBounds in class PointSpringBase
Parameters:
pmin - minimum point
pmax - maximum point

render

public void render(GLRenderer renderer,
                   int flags)
Description copied from interface: GLRenderable
Render this object using Open GL via the JOGL.

Specified by:
render in interface GLRenderable
Specified by:
render in class PointSpringBase
Parameters:
renderer - renderer object which is used to perform the rendering. Provides pointers to GL and GLU, along with helper functions.
flags - supplies flags that may be used to control different aspects of the rendering. Flags are defined in GLRenderer and currently include GLRenderer.SELECTED, GLRenderer.VERTEX_COLORING, GLRenderer.HSV_COLOR_INTERPOLATION, GLRenderer.SORT_FACES, and GLRenderer.CLEAR_MESH_DISPLAY_LISTS.

scaleDistance

public void scaleDistance(double s)
Description copied from interface: ScalableUnits
Scales all distance coordinates.

Specified by:
scaleDistance in interface ScalableUnits
Overrides:
scaleDistance in class PointSpringBase
Parameters:
s - scaling factor

scaleMass

public void scaleMass(double s)
Description copied from interface: ScalableUnits
Scales all mass units.

Specified by:
scaleMass in interface ScalableUnits
Overrides:
scaleMass in class PointSpringBase
Parameters:
s - scaling factor

getDir

public Vector3d getDir()

getLength

public double getLength()
Specified by:
getLength in class PointSpringBase

getLengthDot

public double getLengthDot()

computeForcePositionJacobian

public void computeForcePositionJacobian(Matrix3d M)
Computes the force/position Jacobian of this spring. This gives the change in the force acting on the first point with respect to a change in the position of the first point.

Parameters:
M - matrix in which to return the result

computeForceVelocityJacobian

public void computeForceVelocityJacobian(Matrix3d M)
Computes the force/velocity Jacobian of this spring. This gives the change in the force acting on the first point with respect to a change in the velocity of the first point.

Parameters:
M - matrix in which to return the result

addSolveBlocks

public void addSolveBlocks(SparseNumberedBlockMatrix M)
Description copied from interface: ForceEffector
Adds any needed blocks to a solve matrix in order to accomodate the Jacobian terms associated with this force effector. In general, blocks will be need to be added at locations given by the block indices (bi, bj), where bi and bj correspond to the solve indices (as returned by getSolveIndex) for all dynamic or attached components affected by this force effector.

Specified by:
addSolveBlocks in interface ForceEffector
Parameters:
M - solve matrix to which blocks should be added

addPosJacobian

public void addPosJacobian(SparseNumberedBlockMatrix M,
                           double s)
Description copied from interface: ForceEffector
Scales the components of the position Jacobian associated with this force effector and adds it to the supplied solve matrix M.

M is guaranteed to be the same matrix supplied in the most recent call to addSolveBlocks, and so implementations may choose to cache the relevant matrix blocks from that call, instead of retrieving them directly from M.

Specified by:
addPosJacobian in interface ForceEffector
Parameters:
M - solve matrix to which scaled position Jacobian is to be added
s - scaling factor for position Jacobian

addVelJacobian

public void addVelJacobian(SparseNumberedBlockMatrix M,
                           double s)
Description copied from interface: ForceEffector
Scales the components of the velocity Jacobian associated with this force effector and adds it to the supplied solve matrix M.

M is guaranteed to be the same matrix supplied in the most recent call to addSolveBlocks, and so implementations may choose to cache the relevant matrix blocks from that call, instead of retrieving them directly from M.

Specified by:
addVelJacobian in interface ForceEffector
Parameters:
M - solve matrix to which scaled velocity Jacobian is to be added
s - scaling factor for velocity Jacobian

getJacobianType

public int getJacobianType()
Description copied from interface: ForceEffector
Returns a code indicating the matrix type that results when the Jacobian terms of this force effector are added to the solve matrix. This should be a logical or-ing of either Matrix.SYMMETRIC or Matrix.POSITIVE_DEFINITE. The former should be set if adding the Jacobian terms preserves symmetry, and the latter should be set if positive definiteness if preserved. Both should be set if there is no Jacobian for this effector (i.e., the Jacobian methods are not implemented). Matrix types from all the force effectors are logically and-ed together to determine the type for the entire solve matrix.

Specified by:
getJacobianType in interface ForceEffector
Returns:
solve matrix type resulting from adding Jacobian terms

isDuplicatable

public boolean isDuplicatable()
Returns true if this component can be duplicated. Duplication means that we can expect to be able to make a complete copy of the component along with all it's external references. This method should return true if and only if CopyableComponent.getCopyReferences(java.util.List, artisynth.core.modelbase.ModelComponent) returns true.

This method is not currently used. It is intended to provide a faster way of determining if a component can be duplicated, without having to use CopyableComponent.getCopyReferences(java.util.List, artisynth.core.modelbase.ModelComponent) to build the list of copy references.

Specified by:
isDuplicatable in interface CopyableComponent
Returns:
true if this component can be duplicated.

getCopyReferences

public boolean getCopyReferences(java.util.List<ModelComponent> refs,
                                 ModelComponent ancestor)
Collects external references which must also be copied in order to duplicate this component. These references should exclude those which are contained within a specified component hierarchy. This method should return true if and only if CopyableComponent.isDuplicatable() returns true.

Specified by:
getCopyReferences in interface CopyableComponent
Parameters:
refs - list to which references are appended
ancestor - root node of the hierarchy from which references are to be excluded
Returns:
false if it is discovered that the component cannot be duplicated

copy

public ModelComponent copy(int flags,
                           java.util.Map<ModelComponent,ModelComponent> copyMap)
Description copied from interface: CopyableComponent
Create a copy of this component. If COPY_REFERENCES is set in flags, then any component referenced by this component should itself be set to a copy. This should be done first checking copyMap for an existing copy of the referenced component. If there is no existing copy, then a copy should be created by calling copy recursively and adding the new copy to copyMap.

Specified by:
copy in interface CopyableComponent
Overrides:
copy in class PointSpringBase

getHardReferences

public void getHardReferences(java.util.List<ModelComponent> refs)
Description copied from class: ModelComponentBase
Appends all hard references for this component to a list. References are other components, outside of this component's immediate ancestry, on which this component depends. For example, an AxialSpring refers to two Point components as for it's end points. A hard reference is one which the referring component must have, and which if deleted, implies that the referring component should be deleted too.

Specified by:
getHardReferences in interface ModelComponent
Overrides:
getHardReferences in class ModelComponentBase
Parameters:
refs - list to which hard references are appended