b2Contact Class Reference

#include <b2Contact.h>

Inherited by b2ChainAndCircleContact, b2ChainAndPolygonContact, b2CircleContact, b2EdgeAndCircleContact, b2EdgeAndPolygonContact, b2PolygonAndCircleContact, and b2PolygonContact.

Public Member Functions
b2Manifold *	GetManifold ()
const b2Manifold *	GetManifold () const
void	GetWorldManifold (b2WorldManifold *worldManifold) const
	Get the world manifold.
bool	IsTouching () const
	Is this contact touching?
void	SetEnabled (bool flag)
bool	IsEnabled () const
	Has this contact been disabled?
b2Contact *	GetNext ()
	Get the next contact in the world's contact list.
const b2Contact *	GetNext () const
b2Fixture *	GetFixtureA ()
	Get fixture A in this contact.
const b2Fixture *	GetFixtureA () const
int32	GetChildIndexA () const
	Get the child primitive index for fixture A.
b2Fixture *	GetFixtureB ()
	Get fixture B in this contact.
const b2Fixture *	GetFixtureB () const
int32	GetChildIndexB () const
	Get the child primitive index for fixture B.
void	SetFriction (float32 friction)
float32	GetFriction () const
	Get the friction.
void	ResetFriction ()
	Reset the friction mixture to the default value.
void	SetRestitution (float32 restitution)
float32	GetRestitution () const
	Get the restitution.
void	ResetRestitution ()
	Reset the restitution to the default value.
void	SetTangentSpeed (float32 speed)
	Set the desired tangent speed for a conveyor belt behavior. In meters per second.
float32	GetTangentSpeed () const
	Get the desired tangent speed. In meters per second.
virtual void	Evaluate (b2Manifold *manifold, const b2Transform &xfA, const b2Transform &xfB)=0
	Evaluate this contact with your own manifold and transforms.

Protected Types
enum	{   e_islandFlag = 0x0001, e_touchingFlag = 0x0002, e_enabledFlag = 0x0004, e_filterFlag = 0x0008,   e_bulletHitFlag = 0x0010, e_toiFlag = 0x0020 }

Protected Member Functions
void	FlagForFiltering ()
	Flag this contact for filtering. Filtering will occur the next time step.
	b2Contact (b2Fixture *fixtureA, int32 indexA, b2Fixture *fixtureB, int32 indexB)
void	Update (b2ContactListener *listener)

Static Protected Member Functions
static void	AddType (b2ContactCreateFcn *createFcn, b2ContactDestroyFcn *destroyFcn, b2Shape::Type typeA, b2Shape::Type typeB)
static void	InitializeRegisters ()
static b2Contact *	Create (b2Fixture *fixtureA, int32 indexA, b2Fixture *fixtureB, int32 indexB, b2BlockAllocator *allocator)
static void	Destroy (b2Contact *contact, b2Shape::Type typeA, b2Shape::Type typeB, b2BlockAllocator *allocator)
static void	Destroy (b2Contact *contact, b2BlockAllocator *allocator)

Protected Attributes
uint32	m_flags
b2Contact *	m_prev
b2Contact *	m_next
b2ContactEdge	m_nodeA
b2ContactEdge	m_nodeB
b2Fixture *	m_fixtureA
b2Fixture *	m_fixtureB
int32	m_indexA
int32	m_indexB
b2Manifold	m_manifold
int32	m_toiCount
float32	m_toi
float32	m_friction
float32	m_restitution
float32	m_tangentSpeed

Static Protected Attributes
static b2ContactRegister	s_registers [b2Shape::e_typeCount][b2Shape::e_typeCount]
static bool	s_initialized = false

Friends
class	b2ContactManager
class	b2World
class	b2Body
class	b2Fixture

Detailed Description

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.

Member Function Documentation

b2Manifold * b2Contact::GetManifold ( )

inline

Get the contact manifold. Do not modify the manifold unless you understand the internals of Box2D.

void b2Contact::SetEnabled ( bool  flag )

inline

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).

void b2Contact::SetFriction ( float32  friction )

inline

Override the default friction mixture. You can call this in b2ContactListener::PreSolve. This value persists until set or reset.

void b2Contact::SetRestitution ( float32  restitution )

inline

Override the default restitution mixture. You can call this in b2ContactListener::PreSolve. The value persists until you set or reset.

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The documentation for this class was generated from the following files:

• b2Contact.h
• b2Contact.cpp