b2RevoluteJoint Class Reference

#include <b2RevoluteJoint.h>

Inheritance diagram for b2RevoluteJoint:

List of all members.

Public Member Functions
b2Vec2	GetAnchorA () const
	Get the anchor point on bodyA in world coordinates.
b2Vec2	GetAnchorB () const
	Get the anchor point on bodyB in world coordinates.
b2Vec2	GetReactionForce (float32 inv_dt) const
	Get the reaction force on body2 at the joint anchor in Newtons.
float32	GetReactionTorque (float32 inv_dt) const
	Get the reaction torque on body2 in N*m.
float32	GetJointAngle () const
	Get the current joint angle in radians.
float32	GetJointSpeed () const
	Get the current joint angle speed in radians per second.
bool	IsLimitEnabled () const
	Is the joint limit enabled?
void	EnableLimit (bool flag)
	Enable/disable the joint limit.
float32	GetLowerLimit () const
	Get the lower joint limit in radians.
float32	GetUpperLimit () const
	Get the upper joint limit in radians.
void	SetLimits (float32 lower, float32 upper)
	Set the joint limits in radians.
bool	IsMotorEnabled () const
	Is the joint motor enabled?
void	EnableMotor (bool flag)
	Enable/disable the joint motor.
void	SetMotorSpeed (float32 speed)
	Set the motor speed in radians per second.
float32	GetMotorSpeed () const
	Get the motor speed in radians per second.
void	SetMaxMotorTorque (float32 torque)
	Set the maximum motor torque, usually in N-m.
float32	GetMotorTorque () const
	Get the current motor torque, usually in N-m.
Protected Member Functions
	b2RevoluteJoint (const b2RevoluteJointDef *def)
void	InitVelocityConstraints (const b2TimeStep &step)
void	SolveVelocityConstraints (const b2TimeStep &step)
bool	SolvePositionConstraints (float32 baumgarte)
Protected Attributes
b2Vec2	m_localAnchor1
b2Vec2	m_localAnchor2
b2Vec3	m_impulse
float32	m_motorImpulse
b2Mat33	m_mass
float32	m_motorMass
bool	m_enableMotor
float32	m_maxMotorTorque
float32	m_motorSpeed
bool	m_enableLimit
float32	m_referenceAngle
float32	m_lowerAngle
float32	m_upperAngle
b2LimitState	m_limitState
Friends
class	b2Joint
class	b2GearJoint

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Detailed Description

A revolute joint constrains two bodies to share a common point while they are free to rotate about the point. The relative rotation about the shared point is the joint angle. You can limit the relative rotation with a joint limit that specifies a lower and upper angle. You can use a motor to drive the relative rotation about the shared point. A maximum motor torque is provided so that infinite forces are not generated.

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Constructor & Destructor Documentation

b2RevoluteJoint::b2RevoluteJoint

(

const b2RevoluteJointDef *

def

)

[protected]

---

Member Function Documentation

void b2RevoluteJoint::EnableLimit

(

bool

flag

)

Enable/disable the joint limit.

void b2RevoluteJoint::EnableMotor

(

bool

flag

)

Enable/disable the joint motor.

b2Vec2 b2RevoluteJoint::GetAnchorA

(

)

const [virtual]

Get the anchor point on bodyA in world coordinates.

Implements b2Joint.

b2Vec2 b2RevoluteJoint::GetAnchorB

(

)

const [virtual]

Get the anchor point on bodyB in world coordinates.

Implements b2Joint.

float32 b2RevoluteJoint::GetJointAngle

(

)

const

Get the current joint angle in radians.

float32 b2RevoluteJoint::GetJointSpeed

(

)

const

Get the current joint angle speed in radians per second.

float32 b2RevoluteJoint::GetLowerLimit

(

)

const

Get the lower joint limit in radians.

float32 b2RevoluteJoint::GetMotorSpeed

(

)

const [inline]

Get the motor speed in radians per second.

float32 b2RevoluteJoint::GetMotorTorque

(

)

const

Get the current motor torque, usually in N-m.

b2Vec2 b2RevoluteJoint::GetReactionForce

(

float32

inv_dt

)

const [virtual]

Get the reaction force on body2 at the joint anchor in Newtons.

Implements b2Joint.

float32 b2RevoluteJoint::GetReactionTorque

(

float32

inv_dt

)

const [virtual]

Get the reaction torque on body2 in N*m.

Implements b2Joint.

float32 b2RevoluteJoint::GetUpperLimit

(

)

const

Get the upper joint limit in radians.

void b2RevoluteJoint::InitVelocityConstraints

(

const b2TimeStep &

step

)

[protected, virtual]

Implements b2Joint.

bool b2RevoluteJoint::IsLimitEnabled

(

)

const

Is the joint limit enabled?

bool b2RevoluteJoint::IsMotorEnabled

(

)

const

Is the joint motor enabled?

void b2RevoluteJoint::SetLimits	(	float32	lower,
		float32	upper
	)

Set the joint limits in radians.

void b2RevoluteJoint::SetMaxMotorTorque

(

float32

torque

)

Set the maximum motor torque, usually in N-m.

void b2RevoluteJoint::SetMotorSpeed

(

float32

speed

)

Set the motor speed in radians per second.

bool b2RevoluteJoint::SolvePositionConstraints

(

float32

baumgarte

)

[protected, virtual]

Implements b2Joint.

void b2RevoluteJoint::SolveVelocityConstraints

(

const b2TimeStep &

step

)

[protected, virtual]

Implements b2Joint.

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Friends And Related Function Documentation

friend class b2GearJoint [friend]

friend class b2Joint [friend]

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Member Data Documentation

bool b2RevoluteJoint::m_enableLimit [protected]

bool b2RevoluteJoint::m_enableMotor [protected]

b2Vec3 b2RevoluteJoint::m_impulse [protected]

b2LimitState b2RevoluteJoint::m_limitState [protected]

b2Vec2 b2RevoluteJoint::m_localAnchor1 [protected]

b2Vec2 b2RevoluteJoint::m_localAnchor2 [protected]

float32 b2RevoluteJoint::m_lowerAngle [protected]

b2Mat33 b2RevoluteJoint::m_mass [protected]

float32 b2RevoluteJoint::m_maxMotorTorque [protected]

float32 b2RevoluteJoint::m_motorImpulse [protected]

float32 b2RevoluteJoint::m_motorMass [protected]

float32 b2RevoluteJoint::m_motorSpeed [protected]

float32 b2RevoluteJoint::m_referenceAngle [protected]

float32 b2RevoluteJoint::m_upperAngle [protected]

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

• Box2D/Box2D/Dynamics/Joints/b2RevoluteJoint.h
• Box2D/Box2D/Dynamics/Joints/b2RevoluteJoint.cpp