Class Contact

java.lang.Object
org.jbox2d.dynamics.contacts.Contact
Direct Known Subclasses:
ChainAndCircleContact, ChainAndPolygonContact, CircleContact, EdgeAndCircleContact, EdgeAndPolygonContact, PolygonAndCircleContact, PolygonContact
public abstract class Contact extends java.lang.Object
The class manages contact between two shapes. A contact exists for each overlapping AABB in the broad-phase (except if filtered). Therefore a contact object may exist that has no contact points.

  • Field Details

    • ISLAND_FLAG

      public static final int ISLAND_FLAG
      See Also:

    • TOUCHING_FLAG

      public static final int TOUCHING_FLAG
      See Also:

    • ENABLED_FLAG

      public static final int ENABLED_FLAG
      See Also:

    • FILTER_FLAG

      public static final int FILTER_FLAG
      See Also:

    • BULLET_HIT_FLAG

      public static final int BULLET_HIT_FLAG
      See Also:

    • TOI_FLAG

      public static final int TOI_FLAG
      See Also:

    • m_flags

      public int m_flags

    • m_prev

      public Contact m_prev

    • m_next

      public Contact m_next

    • m_nodeA

      public ContactEdge m_nodeA

    • m_nodeB

      public ContactEdge m_nodeB

    • m_fixtureA

      public Fixture m_fixtureA

    • m_fixtureB

      public Fixture m_fixtureB

    • m_indexA

      public int m_indexA

    • m_indexB

      public int m_indexB

    • m_manifold

      public final Manifold m_manifold

    • m_toiCount

      public float m_toiCount

    • m_toi

      public float m_toi

    • m_friction

      public float m_friction

    • m_restitution

      public float m_restitution

    • m_tangentSpeed

      public float m_tangentSpeed

    • pool

      protected final IWorldPool pool

    • oldManifold

      private final Manifold oldManifold

  • Constructor Details

  • Method Details

    • init

      public void init(Fixture fA, int indexA, Fixture fB, int indexB)
      initialization for pooling

    • getManifold

      public Manifold getManifold()
      Get the contact manifold. Do not set the point count to zero. Instead call Disable.

    • getWorldManifold

      public void getWorldManifold(WorldManifold worldManifold)
      Get the world manifold.

    • isTouching

      public boolean isTouching()
      Is this contact touching
      Returns:

    • setEnabled

      public void setEnabled(boolean flag)
      Enable/disable this contact. This can be used inside the pre-solve contact listener. The contact is only disabled for the current time step (or sub-step in continuous collisions).
      Parameters:
      flag -

    • isEnabled

      public boolean isEnabled()
      Has this contact been disabled?
      Returns:

    • getNext

      public Contact getNext()
      Get the next contact in the world's contact list.
      Returns:

    • getFixtureA

      public Fixture getFixtureA()
      Get the first fixture in this contact.
      Returns:

    • getChildIndexA

      public int getChildIndexA()

    • getFixtureB

      public Fixture getFixtureB()
      Get the second fixture in this contact.
      Returns:

    • getChildIndexB

      public int getChildIndexB()

    • setFriction

      public void setFriction(float friction)

    • getFriction

      public float getFriction()

    • resetFriction

      public void resetFriction()

    • setRestitution

      public void setRestitution(float restitution)

    • getRestitution

      public float getRestitution()

    • resetRestitution

      public void resetRestitution()

    • setTangentSpeed

      public void setTangentSpeed(float speed)

    • getTangentSpeed

      public float getTangentSpeed()

    • evaluate

      public abstract void evaluate(Manifold manifold, Transform xfA, Transform xfB)

    • flagForFiltering

      public void flagForFiltering()
      Flag this contact for filtering. Filtering will occur the next time step.

    • update

      public void update(ContactListener listener)

    • mixFriction

      public static final float mixFriction(float friction1, float friction2)
      Friction mixing law. The idea is to allow either fixture to drive the restitution to zero. For example, anything slides on ice.
      Parameters:
      friction1 -
      friction2 -
      Returns:

    • mixRestitution

      public static final float mixRestitution(float restitution1, float restitution2)
      Restitution mixing law. The idea is allow for anything to bounce off an inelastic surface. For example, a superball bounces on anything.
      Parameters:
      restitution1 -
      restitution2 -
      Returns: