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MdtContact.h File Reference

MdtContact API functions. More...

#include "MePrecision.h"
#include "MdtTypes.h"

Functions
MdtContactID	MdtContactCreate (const MdtWorldID w, const MdtBodyID b1, const MdtBodyID b2)
	Creates a new contact and sets default parameters. More...
void	MdtContactReset (const MdtContactID c)
	Sets a contact to its default values. More...
void	MdtContactDestroy (const MdtContactID c)
	Destroys a constraint. More...
void	MdtContactLog (const MdtContactID c)
	Debug function - output constraint using MeMessage. More...
MdtConstraintID	MdtContactQuaConstraint (const MdtContactID c)
	Gets an MdtConstraintID from a specific constraint for performing functions common to all constraints. More...
void	MdtContactGetPosition (const MdtContactID c, MeVector3 v)
	Returns the contact position in v, in the world reference frame. More...
void	MdtContactGetNormal (const MdtContactID c, MeVector3 v)
	Returns the contact normal in v, in the world reference frame. More...
MeReal	MdtContactGetPenetration (const MdtContactID c)
	Returns the current penetration at this contact. More...
void	MdtContactGetDirection (const MdtContactID c, MeVector3 v)
	The contacts primary direction is returned in v, in the world reference frame. More...
MdtContactParamsID	MdtContactGetParams (const MdtContactID c)
	Returns a pointer to the contacts parameters of this contact. More...
MdtContactID	MdtContactGetNext (const MdtContactID c)
	Returns the pointer to the next contact associated with this body pair if it was set in collision. More...
void	MdtContactSetPosition (const MdtContactID c, const MeReal x, const MeReal y, const MeReal z)
	Sets the contact position. More...
void	MdtContactSetNormal (const MdtContactID c, const MeReal x, const MeReal y, const MeReal z)
	Sets the contact normal. More...
void	MdtContactSetPenetration (const MdtContactID c, const MeReal p)
	Sets the amount of penetration at the contact. More...
void	MdtContactSetDirection (const MdtContactID c, const MeReal x, const MeReal y, const MeReal z)
	Sets the primary direction for this contact. More...
void	MdtContactSetParams (const MdtContactID c, const MdtContactParamsID p)
	Utility for setting all contact parameters. More...
void	MdtContactSetNext (const MdtContactID c, const MdtContactID nc)
	Sets the pointer to the next contact. More...
Variables
const MdtContactID	MdtContactInvalidID = 0
	Invalid ContactID indicating end of MdtContact linked list. More...

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Detailed Description

MdtContact API functions.

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Define Documentation

#define MdtContactDisable( c )

Initializer:

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                            MdtConstraintDisable(MdtContactQuaConstraint(c))

#define MdtContactEnable( c )

Initializer:

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                            MdtConstraintEnable(MdtContactQuaConstraint(c))

#define MdtContactGetBody( c, bodyindex )

Initializer:

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                            MdtConstraintGetBody(MdtContactQuaConstraint(c), bodyindex)

#define MdtContactGetForce( c, bodyindex, f )

Initializer:

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                            MdtConstraintGetForce(MdtContactQuaConstraint(c), bodyindex, f)

#define MdtContactGetTorque( c, bodyindex, t )

Initializer:

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                            MdtConstraintGetTorque(MdtContactQuaConstraint(c), bodyindex, t)

#define MdtContactGetUserData( c )

Initializer:

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                            MdtConstraintGetUserData(MdtContactQuaConstraint(c))

#define MdtContactGetWorld( c )

Initializer:

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                            MdtConstraintGetWorld(MdtContactQuaConstraint(c))

#define MdtContactIsEnabled( c )

Initializer:

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                            MdtConstraintIsEnabled(MdtContactQuaConstraint(c))

#define MdtContactSetBodies( c, b1, b2 )

Initializer:

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                            MdtConstraintSetBodies(MdtContactQuaConstraint(c), b1, b2)

#define MdtContactSetUserData( c, d )

Initializer:

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                            MdtConstraintSetUserData(MdtContactQuaConstraint(c), d)

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Function Documentation

MdtContactID MdtContactCreate ( MdtWorldID w, MdtBodyID b1, MdtBodyID b2 )

Creates a new contact and sets default parameters.

A contact's bodies may not be known on creation because a pool might have been created and the bodies set when needed. Therefore it is okay to set both bodies to zero here. If however something other than zero is specified for either body then that body will be tested to see if it is valid.

See also:

MdtContactReset()

void MdtContactDestroy ( MdtContactID c )

Destroys a constraint.

void MdtContactGetDirection ( MdtContactID c, MeVector3 v )

The contacts primary direction is returned in v, in the world reference frame.

MdtContactID MdtContactGetNext ( MdtContactID c )

Returns the pointer to the next contact associated with this body pair if it was set in collision.

If the return value is equal to MdtContactInvalidID then no next contact exists.

void MdtContactGetNormal ( MdtContactID c, MeVector3 v )

Returns the contact normal in v, in the world reference frame.

MdtContactParamsID MdtContactGetParams ( MdtContactID c )

Returns a pointer to the contacts parameters of this contact.

MeReal MdtContactGetPenetration ( MdtContactID c )

Returns the current penetration at this contact.

void MdtContactGetPosition ( MdtContactID c, MeVector3 v )

Returns the contact position in v, in the world reference frame.

void MdtContactLog ( MdtContactID c )

Debug function - output constraint using MeMessage.

MdtConstraintID MdtContactQuaConstraint ( MdtContactID c )

Gets an MdtConstraintID from a specific constraint for performing functions common to all constraints.

void MdtContactReset ( MdtContactID c )

Sets a contact to its default values.

Note that the contact's bodies are not reset.

Default values:

• position = {0,0,0}
• normal = {0,1,0}
• friction direction = {0,1,0}
• penetration = 0

Parameters:

c	contact ID

See also:

MdtContactParamsReset()

void MdtContactSetDirection ( MdtContactID c, MeReal x, MeReal y, MeReal z )

Sets the primary direction for this contact.

This is only necessary if you wish to define surface properties to vary depending on the direction. For isotropic (the same in all direction) contacts, this function should not be called, and the primary and secondary parameters should be set to the same value.

The direction should always be perpendicular to the given normal, and the secondary direction is perpendicular to the primary direction.

void MdtContactSetNext ( MdtContactID c, MdtContactID nc )

Sets the pointer to the next contact.

Used by Mcd collision.

void MdtContactSetNormal ( MdtContactID c, MeReal x, MeReal y, MeReal z )

Sets the contact normal.

void MdtContactSetParams ( MdtContactID c, MdtContactParamsID p )

Utility for setting all contact parameters.

Allows the user to set all values in the MdtBclContactParams structure in one go.

void MdtContactSetPenetration ( MdtContactID c, MeReal p )

Sets the amount of penetration at the contact.

void MdtContactSetPosition ( MdtContactID c, MeReal x, MeReal y, MeReal z )

Sets the contact position.

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Variable Documentation

const MdtContactID MdtContactInvalidID = 0

Invalid ContactID indicating end of MdtContact linked list.

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