HingeJoint Class Reference

#include <Joints.h>

Inherits Joint.

Collaboration diagram for HingeJoint:

[legend]

List of all members.

Public Member Functions
	HingeJoint ()
virtual	~HingeJoint ()
void	setMainEntity (int id)
void	setAnchor (float anchorX, float anchorY, float anchorZ)
void	setAxis (float axisX, float axisY, float axisZ)
void	setAngles (float min, float max)
void	checkAngles ()
virtual void	getMemberValue (std::string type, void *result)
virtual void	setMemberValue (std::string type, void *source)
Protected Member Functions
virtual void	attachJoint (dBodyID obj1, dBodyID obj2)
virtual void	detachJoint ()
void	setODEAngles ()
Protected Attributes
gmtl::Vec3f	anchor
gmtl::Vec3f	axis
float	minAngle
float	maxAngle
float	deltaAngle
float	deltaAngleODE
float	oldAngle
bool	anglesSet
bool	firstIsMain

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Detailed Description

This class represents an hinge joint which can be defined by an Anchor of the Axis and the Axis itself. There is also the option to set the maximum and minimum angle of the joint.

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Constructor & Destructor Documentation

HingeJoint::HingeJoint

(

)

virtual HingeJoint::~HingeJoint

(

)

[inline, virtual]

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Member Function Documentation

void HingeJoint::attachJoint	(	dBodyID	obj1,
		dBodyID	obj2
	)			[protected, virtual]

This method is called if the joint should be attached. It creates the ODE-joint, calculates the current anchor-position and axis-orientation and attaches the Joint.

Parameters:

	obj1	first ODE-object to attach with
	obj2	second ODE-object to attach with

Implements Joint.

void HingeJoint::checkAngles

(

)

This method checks the angle of the HingeJoint for correctness and corrects it if needed. This is necessary because ODE stores the hinge-angle between -180 degrees and +180 degrees. If the angle gets above +180 deg ODE swaps to -180 deg and vice versa. If a user wants to use a HingeJoint with a maximum angle above 180 deg or a minimum angle below 180 deg the method corrects the ODE-swapping.

void HingeJoint::detachJoint

(

)

[protected, virtual]

This method is called if the joint should be detached. If the maximum and minimum angles are set the method stores the angle-offset for correct angles in later use.

Implements Joint.

void HingeJoint::getMemberValue	(	std::string	type,
		void *	result
	)			[virtual]

This method copies the value of the field with the passed name to the result-pointer. It is a little helper to avoid type-casts when accessing joint-pointers.

Parameters:

	type	name of the field
	result	destination where the value should be stored

Implements Joint.

void HingeJoint::setAnchor	(	float	anchorX,
		float	anchorY,
		float	anchorZ
	)

This method sets the Anchor of the Joint in OBJECT-COORDINATES!!! This means that the Anchor is relative to the position of the main EntityTransform. Take care that the Anchor-offset is also scaled by the scale-Value of the EntityTransform. The reason for using object coordinates is because modelers can easily read the offset out of the modelling application.

Parameters:

	anchorX	X-position of the Anchor
	anchorY	Y-position of the Anchor
	anchorZ	Z-position of the Anchor

void HingeJoint::setAngles	(	float	min,
		float	max
	)

This method sets the maximum and minimum angle of the Axis.

Parameters:

	min	minimum Angle in rad
	max	maximum Angle in rad

void HingeJoint::setAxis	(	float	axisX,
		float	axisY,
		float	axisZ
	)

This method sets the Axis of the Joint in OBJECT-COORDINATES!!! This means that the axis is rotated by the rotation-value of the main EntityTransform.

Parameters:

	axisX	X-value of the Axis
	axisY	Y-value of the Axis
	axisZ	Z-value of the Axis

void HingeJoint::setMainEntity

(

int

id

)

[virtual]

This method sets the main EntityTransform, where the Joint should be attached to.

Parameters:

id

1 for the first EntityTransform, 2 for the second one

Reimplemented from Joint.

void HingeJoint::setMemberValue	(	std::string	type,
		void *	source
	)			[virtual]

Implements Joint.

void HingeJoint::setODEAngles

(

)

[protected]

This method sets the minimum and maximum angle of the ODE-hinge joint. The method checks if the first or the second EntityTransform is the mainEntity, because then the angles have to be set into different directions. The maxAngle-parameter is set two times, because ODE only accepts it if the maximum angle is above the minimum angle. To avoid checking this we easily set it two times.

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Member Data Documentation

gmtl::Vec3f HingeJoint::anchor [protected]

bool HingeJoint::anglesSet [protected]

gmtl::Vec3f HingeJoint::axis [protected]

float HingeJoint::deltaAngle [protected]

float HingeJoint::deltaAngleODE [protected]

bool HingeJoint::firstIsMain [protected]

float HingeJoint::maxAngle [protected]

float HingeJoint::minAngle [protected]

float HingeJoint::oldAngle [protected]

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

• src/inVRs/Modules/JointInteraction/Joints.h
• src/inVRs/Modules/JointInteraction/Joints.cpp