Box2D: b2World Class Reference

Box2D

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b2World Class Reference

The world class manages all physics entities, dynamic simulation, and asynchronous queries. More...

List of all members.

Public Member Functions

 b2World (const b2AABB &worldAABB, const b2Vec2 &gravity, bool doSleep)
 Construct a world object.
 ~b2World ()
 Destruct the world. All physics entities are destroyed and all heap memory is released.
void SetDestructionListener (b2DestructionListener *listener)
 Register a destruction listener.
void SetBoundaryListener (b2BoundaryListener *listener)
 Register a broad-phase boundary listener.
void SetContactFilter (b2ContactFilter *filter)
 Register a contact filter to provide specific control over collision.
void SetContactListener (b2ContactListener *listener)
 Register a contact event listener.
void SetDebugDraw (b2DebugDraw *debugDraw)
 Register a routine for debug drawing.
b2Body * CreateBody (const b2BodyDef *def)
 Create a rigid body given a definition.
void DestroyBody (b2Body *body)
 Destroy a rigid body given a definition.
b2Joint * CreateJoint (const b2JointDef *def)
 Create a joint to constrain bodies together.
void DestroyJoint (b2Joint *joint)
 Destroy a joint.
b2Body * GetGroundBody ()
 The world provides a single static ground body with no collision shapes.
void Step (float32 timeStep, int32 iterations)
 Take a time step.
int32 Query (const b2AABB &aabb, b2Shape **shapes, int32 maxCount)
 Query the world for all shapes that potentially overlap the provided AABB.
b2Body * GetBodyList ()
 Get the world body list.
b2Joint * GetJointList ()
 Get the world joint list.
void Refilter (b2Shape *shape)
 Re-filter a shape. This re-runs contact filtering on a shape.
void SetWarmStarting (bool flag)
 Enable/disable warm starting. For testing.
void SetPositionCorrection (bool flag)
 Enable/disable position correction. For testing.
void SetContinuousPhysics (bool flag)
 Enable/disable continuous physics. For testing.
void Validate ()
 Perform validation of internal data structures.
int32 GetProxyCount () const
 Get the number of broad-phase proxies.
int32 GetPairCount () const
 Get the number of broad-phase pairs.
int32 GetBodyCount () const
 Get the number of bodies.
int32 GetJointCount () const
 Get the number joints.
int32 GetContactCount () const
 Get the number of contacts (each may have 0 or more contact points).
void SetGravity (const b2Vec2 &gravity)
 Change the global gravity vector.

Friends

class b2Body

Detailed Description

The world class manages all physics entities, dynamic simulation, and asynchronous queries.

The world also contains efficient memory management facilities.

Constructor & Destructor Documentation

b2World::b2World ( const b2AABB &  worldAABB,
const b2Vec2 &  gravity,
bool  doSleep 
)

Construct a world object.

Parameters:
worldAABB a bounding box that completely encompasses all your shapes.
gravity the world gravity vector.
doSleep improve performance by not simulating inactive bodies.

Member Function Documentation

void b2World::SetContactFilter ( b2ContactFilter *  filter  ) 

Register a contact filter to provide specific control over collision.

Otherwise the default filter is used (b2_defaultFilter).

void b2World::SetDebugDraw ( b2DebugDraw *  debugDraw  ) 

Register a routine for debug drawing.

The debug draw functions are called inside the b2World::Step method, so make sure your renderer is ready to consume draw commands when you call Step().

b2Body * b2World::CreateBody ( const b2BodyDef *  def  ) 

Create a rigid body given a definition.

No reference to the definition is retained.

Warning:
This function is locked during callbacks.

void b2World::DestroyBody ( b2Body *  body  ) 

Destroy a rigid body given a definition.

No reference to the definition is retained. This function is locked during callbacks.

Warning:
This automatically deletes all associated shapes and joints.

This function is locked during callbacks.

b2Joint * b2World::CreateJoint ( const b2JointDef *  def  ) 

Create a joint to constrain bodies together.

No reference to the definition is retained. This may cause the connected bodies to cease colliding.

Warning:
This function is locked during callbacks.

void b2World::DestroyJoint ( b2Joint *  joint  ) 

Destroy a joint.

This may cause the connected bodies to begin colliding.

Warning:
This function is locked during callbacks.

b2Body * b2World::GetGroundBody (  )  [inline]

The world provides a single static ground body with no collision shapes.

You can use this to simplify the creation of joints and static shapes.

void b2World::Step ( float32  timeStep,
int32  iterations 
)

Take a time step.

This performs collision detection, integration, and constraint solution.

Parameters:
timeStep the amount of time to simulate, this should not vary.
iterations the number of iterations to be used by the constraint solver.

int32 b2World::Query ( const b2AABB &  aabb,
b2Shape **  shapes,
int32  maxCount 
)

Query the world for all shapes that potentially overlap the provided AABB.

You provide a shape pointer buffer of specified size. The number of shapes found is returned.

Parameters:
aabb the query box.
shapes a user allocated shape pointer array of size maxCount (or greater).
maxCount the capacity of the shapes array.
Returns:
the number of shapes found in aabb.

b2Body * b2World::GetBodyList (  )  [inline]

Get the world body list.

With the returned body, use b2Body::GetNext to get the next body in the world list. A NULL body indicates the end of the list.

Returns:
the head of the world body list.

b2Joint * b2World::GetJointList (  )  [inline]

Get the world joint list.

With the returned joint, use b2Joint::GetNext to get the next joint in the world list. A NULL joint indicates the end of the list.

Returns:
the head of the world joint list.

The documentation for this class was generated from the following files:
  • b2World.h
  • b2World.cpp
Generated on Sun Apr 13 15:21:27 2008 for Box2D by  doxygen 1.5.4

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