Box2D  2.4.1
A 2D physics engine for games
b2DistanceJoint Class Reference

#include <b2_distance_joint.h>

Inheritance diagram for b2DistanceJoint:

Public Member Functions

b2Vec2 GetAnchorA () const override
 Get the anchor point on bodyA in world coordinates.
b2Vec2 GetAnchorB () const override
 Get the anchor point on bodyB in world coordinates.
b2Vec2 GetReactionForce (float inv_dt) const override
float GetReactionTorque (float inv_dt) const override
const b2Vec2GetLocalAnchorA () const
 The local anchor point relative to bodyA's origin.
const b2Vec2GetLocalAnchorB () const
 The local anchor point relative to bodyB's origin.
float GetLength () const
 Get the rest length.
float SetLength (float length)
float GetMinLength () const
 Get the minimum length.
float SetMinLength (float minLength)
float GetMaxLength () const
 Get the maximum length.
float SetMaxLength (float maxLength)
float GetCurrentLength () const
 Get the current length.
void SetStiffness (float stiffness)
 Set/get the linear stiffness in N/m.
float GetStiffness () const
void SetDamping (float damping)
 Set/get linear damping in N*s/m.
float GetDamping () const
void Dump () override
 Dump joint to dmLog.
void Draw (b2Draw *draw) const override
 Debug draw this joint.
- Public Member Functions inherited from b2Joint
b2JointType GetType () const
 Get the type of the concrete joint.
b2BodyGetBodyA ()
 Get the first body attached to this joint.
b2BodyGetBodyB ()
 Get the second body attached to this joint.
b2JointGetNext ()
 Get the next joint the world joint list.
const b2JointGetNext () const
b2JointUserDataGetUserData ()
 Get the user data pointer.
bool IsEnabled () const
 Short-cut function to determine if either body is enabled.
bool GetCollideConnected () const
virtual void ShiftOrigin (const b2Vec2 &newOrigin)
 Shift the origin for any points stored in world coordinates.

Protected Member Functions

 b2DistanceJoint (const b2DistanceJointDef *data)
void InitVelocityConstraints (const b2SolverData &data) override
void SolveVelocityConstraints (const b2SolverData &data) override
bool SolvePositionConstraints (const b2SolverData &data) override
- Protected Member Functions inherited from b2Joint
 b2Joint (const b2JointDef *def)

Protected Attributes

float m_stiffness
float m_damping
float m_bias
float m_length
float m_minLength
float m_maxLength
b2Vec2 m_localAnchorA
b2Vec2 m_localAnchorB
float m_gamma
float m_impulse
float m_lowerImpulse
float m_upperImpulse
int32 m_indexA
int32 m_indexB
b2Vec2 m_u
b2Vec2 m_rA
b2Vec2 m_rB
b2Vec2 m_localCenterA
b2Vec2 m_localCenterB
float m_currentLength
float m_invMassA
float m_invMassB
float m_invIA
float m_invIB
float m_softMass
float m_mass
- Protected Attributes inherited from b2Joint
b2JointType m_type
b2JointEdge m_edgeA
b2JointEdge m_edgeB
int32 m_index
bool m_islandFlag
bool m_collideConnected
b2JointUserData m_userData


class b2Joint

Additional Inherited Members

- Static Protected Member Functions inherited from b2Joint
static b2JointCreate (const b2JointDef *def, b2BlockAllocator *allocator)
static void Destroy (b2Joint *joint, b2BlockAllocator *allocator)

Detailed Description

A distance joint constrains two points on two bodies to remain at a fixed distance from each other. You can view this as a massless, rigid rod.

Member Function Documentation

◆ GetReactionForce()

b2Vec2 b2DistanceJoint::GetReactionForce ( float  inv_dt) const

Get the reaction force given the inverse time step. Unit is N.

Implements b2Joint.

◆ GetReactionTorque()

float b2DistanceJoint::GetReactionTorque ( float  inv_dt) const

Get the reaction torque given the inverse time step. Unit is N*m. This is always zero for a distance joint.

Implements b2Joint.

◆ SetLength()

float b2DistanceJoint::SetLength ( float  length)

Set the rest length

clamped rest length

◆ SetMaxLength()

float b2DistanceJoint::SetMaxLength ( float  maxLength)

Set the maximum length

the clamped maximum length

◆ SetMinLength()

float b2DistanceJoint::SetMinLength ( float  minLength)

Set the minimum length

the clamped minimum length

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