artisynth.core.mechmodels

Class ContactData

java.lang.Object

artisynth.core.mechmodels.ContactData

public class ContactData
extends java.lang.Object

Information about a single contact constraint that is needed for later processing, either in a collision response or for rendering.

Constructor Summary

Constructors

Constructor and Description
ContactData() Constructs a new, empty ContactConstraintData object.
ContactData(ContactConstraint cons, boolean isBilateral) Constructs a ContactConstraintData object from the data in a ContactConstraint.

Method Summary

Modifier and Type	Method and Description
Vector3d	getContactForce() Returns the contact force associated with this contact.
double	getContactForceScalar() Returns the value of the contact force along the contact normal.
ContactPoint	getContactPoint0() Returns the first point of this contact.
ContactPoint	getContactPoint1() Returns the second point of this contact.
Vector3d	getFrictionForce() Returns the friction force associated with this contact.
Vector3d	getNormal() Returns the normal associated with this contact.
Point3d	getPosition0() Returns the position of the first point of this contact, in world coordinates.
Point3d	getPosition1() Returns the position of the second point of this contact, in world coordinates.
void	getState(DataBuffer data) Saves the information of this ContactContraintData into a data buffer.
boolean	point0OnCollidable1() Queries whether the first contact point is on the second collidable of this contact.
void	setState(DataBuffer data, CollidableBody collidable0, CollidableBody collidable1) Loads the information of this ContactContraintData from a data buffer, using the contact's collidable bodies to supply additional information.

Methods inherited from class java.lang.Object

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

Constructor Detail

ContactData

public ContactData()

Constructs a new, empty ContactConstraintData object.

ContactData

public ContactData(ContactConstraint cons,
                   boolean isBilateral)

Constructs a ContactConstraintData object from the data in a ContactConstraint.

Parameters:

cons - constraint providing the contact data

isBilateral - if true, indicates the contact constraint is bilateral

Method Detail

getContactPoint0

public ContactPoint getContactPoint0()

Returns the first point of this contact.

Returns:

first contact point. Should not be modified.

getPosition0

public Point3d getPosition0()

Returns the position of the first point of this contact, in world coordinates.

Returns:

first point position. Should not be modified.

point0OnCollidable1

public boolean point0OnCollidable1()

Queries whether the first contact point is on the second collidable of this contact. If true, the first point is on the second collidable and the second point is on the first collidable. This condition can only occur for collisions using vertex penetration (see CollisionBehavior.Method). Otherwise, the first point is on the first collidable and the second point is on the second collidable.

Returns:

if the first contact point is on the second collidable

getContactPoint1

public ContactPoint getContactPoint1()

Returns the second point of this contact.

Returns:

second contact point. Should not be modified.

getPosition1

public Point3d getPosition1()

Returns the position of the second point of this contact, in world coordinates.

Returns:

second point position. Should not be modified.

getContactForceScalar

public double getContactForceScalar()

Returns the value of the contact force along the contact normal. The value is usually positive, but may briefly be negative when contact is being handled using bilateral constraints which have not yet separated.

Returns:

contact force scalar

getContactForce

public Vector3d getContactForce()

Returns the contact force associated with this contact. The force lies in the same direction as the contact normal, and is given by lam * nrm, where lam and nrm are the values returned by getContactForceScalar() and getNormal().

Returns:

contact force

getFrictionForce

public Vector3d getFrictionForce()

Returns the friction force associated with this contact. The force, if any, will be perpendicular to the contact normal.

Returns:

friction force. Should not be modified.

getNormal

public Vector3d getNormal()

Returns the normal associated with this contact. The normal has unit length and is directed from the first contact point (returned by getContactPoint0()), and directed toward the second contact point (returned by getContactPoint0()).

Returns:

contact normal. Should not be modified.

getState

public void getState(DataBuffer data)

Saves the information of this ContactContraintData into a data buffer.

Parameters:

data - buffer in which to store information

setState

public void setState(DataBuffer data,
                     CollidableBody collidable0,
                     CollidableBody collidable1)

Loads the information of this ContactContraintData from a data buffer, using the contact's collidable bodies to supply additional information.

Parameters:

data - buffer from which to get information

collidable0 - first collidable body associated with this contact

collidable1 - second collidable body associated with this contact