Box2D  2.2.1
A 2D Physics Engine for Games
Public Member Functions | Protected Member Functions | Protected Attributes | Friends
b2PulleyJoint Class Reference

#include <b2PulleyJoint.h>

Inheritance diagram for b2PulleyJoint:
b2Joint

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 bodyB at the joint anchor in Newtons.
float32 GetReactionTorque (float32 inv_dt) const
 Get the reaction torque on bodyB in N*m.
b2Vec2 GetGroundAnchorA () const
 Get the first ground anchor.
b2Vec2 GetGroundAnchorB () const
 Get the second ground anchor.
float32 GetLengthA () const
 Get the current length of the segment attached to bodyA.
float32 GetLengthB () const
 Get the current length of the segment attached to bodyB.
float32 GetRatio () const
 Get the pulley ratio.
void Dump ()
 Dump joint to dmLog.

Protected Member Functions

 b2PulleyJoint (const b2PulleyJointDef *data)
void InitVelocityConstraints (const b2SolverData &data)
void SolveVelocityConstraints (const b2SolverData &data)
bool SolvePositionConstraints (const b2SolverData &data)

Protected Attributes

b2Vec2 m_groundAnchorA
b2Vec2 m_groundAnchorB
float32 m_lengthA
float32 m_lengthB
b2Vec2 m_localAnchorA
b2Vec2 m_localAnchorB
float32 m_constant
float32 m_ratio
float32 m_impulse
int32 m_indexA
int32 m_indexB
b2Vec2 m_uA
b2Vec2 m_uB
b2Vec2 m_rA
b2Vec2 m_rB
b2Vec2 m_localCenterA
b2Vec2 m_localCenterB
float32 m_invMassA
float32 m_invMassB
float32 m_invIA
float32 m_invIB
float32 m_mass

Friends

class b2Joint

Detailed Description

The pulley joint is connected to two bodies and two fixed ground points. The pulley supports a ratio such that: length1 + ratio * length2 <= constant Yes, the force transmitted is scaled by the ratio. Warning: the pulley joint can get a bit squirrelly by itself. They often work better when combined with prismatic joints. You should also cover the the anchor points with static shapes to prevent one side from going to zero length.


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