QSoftBody Class Reference

QSoftBody is a body type that defines deformable, soft objects in the physics world. Mass-spring model is used for simulation dynamics in soft bodies. In the mass-spring model, there are particles with mass that can move individually and interact with the physics world, and these particles can be connected to each other with spring constraints. Additionally, with some user-configurable options specific to the simulation, particles can be subjected to constraints obtained from some calculations. For example, you can add a constraint that ensures particles remain faithful to their initially defined local positions using the "shape matching" option. You can apply a constraint that gives the feeling that the polygon are filled with gas and maintains their area using the "area preserving" option. You can use options that allow particles to collide with each other with a specific radius, and create objects called PBD (Position Based Dynamics). QSoftBody objects inherently require a more flexible configuration than other body types and contain many options. More...

#include <qsoftbody.h>

Inheritance diagram for QSoftBody:

Collaboration diagram for QSoftBody:

Public Member Functions
QSoftBody *	SetRigidity (float value)
QSoftBody *	SetAreaPreservingRate (float value)
QSoftBody *	SetAreaPreservingRigidity (float value)
QSoftBody *	SetAreaPreservingEnabled (bool value)
QSoftBody *	SetTargetPreservationArea (float value)
QSoftBody *	SetSelfCollisionsEnabled (bool value)
QSoftBody *	SetSelfCollisionsSpecifiedRadius (float value)
QSoftBody *	SetPassivationOfInternalSpringsEnabled (bool value)
QSoftBody *	SetShapeMatchingEnabled (bool value, bool withoutInternals=false)
QSoftBody *	SetShapeMatchingRate (float value)
QSoftBody *	SetShapeMatchingFixedTransformEnabled (bool value)
QSoftBody *	SetShapeMatchingFixedPosition (QVector value)
QSoftBody *	SetShapeMatchingFixedRotation (float value)
QSoftBody *	SetParticleSpesificMass (float value)
QSoftBody *	SetParticleSpesificMassEnabled (bool value)
float	GetMass ()
float	GetRigidity ()
float	GetAreaPreservingRate ()
float	GetAreaPreservingRigidity ()
bool	GetAreaPreservingEnabled ()
float	GetTargetPreservationArea ()
bool	GetSelfCollisionsEnabled ()
float	GetSelfCollisionsSpecifiedRadius ()
bool	GetPassivationOfInternalSpringsEnabled ()
bool	GetShapeMatchingEnabled ()
float	GetShapeMatchingRate ()
bool	GetShapeMatchingFixedTransformEnabled ()
QVector	GetShapeMatchingFixedPosition ()
float	GetShapeMatchingFixedRotation ()
float	GetParticleSpesificMass ()
bool	GetParticleSpesificMassEnabled ()
virtual void	Update ()
virtual void	PostUpdate ()
void	PreserveAreas ()
void	ApplyShapeMatching ()
Public Member Functions inherited from QBody
virtual void	OnPreStep ()
virtual void	OnStep ()
virtual bool	OnCollision (CollisionInfo)
BodyTypes	GetBodyType ()
QWorld *	GetWorld ()
QVector	GetPosition ()
QVector	GetPreviousPosition ()
float	GetRotation ()
float	GetRotationDegree ()
float	GetPreviousRotation ()
QAABB	GetAABB () const
float	GetTotalInitialArea ()
float	GetTotalPolygonsInitialArea ()
float	GetTotalArea ()
float	GetTotalPolygonsArea ()
Modes	GetMode ()
float	GetInertia ()
int	GetLayersBit ()
int	GetCollidableLayersBit ()
bool	GetOverlapWithCollidableLayersBit (int layersBit)
bool	GetOverlapWithLayersBit (int layersBit)
bool	GetIsSleeping ()
bool	GetCanSleep ()
SimulationModels	GetSimulationModel ()
float	GetFriction ()
float	GetStaticFriction ()
float	GetAirFriction ()
float	GetRestitution ()
float	GetCircumference ()
bool	GetBodySpecificTimeScaleEnabled ()
float	GetBodySpesificTimeScale ()
bool	GetEnabled ()
float	GetVelocityLimit ()
bool	GetIntegratedVelocitiesEnabled ()
QBody *	SetPosition (QVector value, bool withPreviousPosition=true)
QBody *	AddPosition (QVector value, bool withPreviousPosition=true)
QBody *	SetPreviousPosition (QVector value)
QBody *	AddPreviousPosition (QVector value)
QBody *	SetRotation (float angleRadian, bool withPreviousRotation=true)
QBody *	SetRotationDegree (float degree, bool withPreviousRotation=true)
QBody *	AddRotation (float angleRadian, bool withPreviousRotation=true)
QBody *	SetPreviousRotation (float angleRadian)
QBody *	AddPreviousRotation (float angleRadian)
QBody *	SetLayersBit (int value)
QBody *	SetCollidableLayersBit (int value)
QBody *	SetCanSleep (bool value)
QBody *	SetMode (QBody::Modes bodyMode)
QBody *	SetSimulationModel (SimulationModels model)
QBody *	SetFriction (float value)
QBody *	SetStaticFriction (float value)
QBody *	SetAirFriction (float value)
QBody *	SetMass (float value)
QBody *	SetRestitution (float value)
QBody *	SetBodySpecificTimeScaleEnabled (bool value)
QBody *	SetBodySpecificTimeScale (float value)
QBody *	SetEnabled (bool value)
QBody *	SetIntegratedVelocitiesEnabled (bool value)
QBody *	AddMesh (QMesh *mesh)
QBody *	RemoveMeshAt (int index)
QMesh *	GetMeshAt (int index)
int	GetMeshCount ()
vector< QMesh * > *	GetMeshes ()
QBody *	AddMeshesFromFile (string filePath)
QBody *	WakeUp ()
QBody *	SetVelocityLimit (float value)

Additional Inherited Members
Public Types inherited from QBody
enum	Modes { DYNAMIC , STATIC }
enum	BodyTypes { RIGID , AREA , SOFT }
enum	SimulationModels { MASS_SPRING , RIGID_BODY }
Public Attributes inherited from QBody
std::function< void(QBody *body)>	PreStepEventListener
std::function< void(QBody *body)>	StepEventListener
std::function< bool(QBody *body, CollisionInfo)>	CollisionEventListener
Protected Member Functions inherited from QBody
void	UpdateAABB ()
void	UpdateMeshTransforms ()
virtual bool	CanGiveCollisionResponseTo (QBody *otherBody)
Static Protected Member Functions inherited from QBody
static QVector	ComputeFriction (QBody *bodyA, QBody *bodyB, QVector &normal, float penetration, QVector &relativeVelocity)
static bool	CanCollide (QBody *bodyA, QBody *bodyB, bool checkBodiesAreEnabled=true)
Protected Attributes inherited from QBody
QWorld *	world
QVector	position =QVector(0,0)
QVector	prevPosition =QVector::Zero()
float	rotation =0.0f
float	prevRotation =0.0f
QAABB	aabb
Modes	mode =QBody::Modes::DYNAMIC
bool	inertiaNeedsUpdate =true
bool	circumferenceNeedsUpdate =true
bool	enableBodySpecificTimeScale =false
float	bodySpecificTimeScale =1.0f
BodyTypes	bodyType =BodyTypes::RIGID
bool	enabled =true
float	velocityLimit =0.0f
bool	enableIntegratedVelocities =true
float	friction =0.2f
float	staticFriction =0.5f
float	airFriction =0.01f
float	mass =1.0f
float	restitution =0.0f
int	layersBit =1
int	collidableLayersBit =1
bool	isKinematic =false
bool	allowKinematicCollisions =false
bool	isSleeping =false
int	sleepTick =120
int	fixedVelocityTick =0
int	fixedAngularTick =0
bool	canSleep =true
vector< QMesh * >	_meshes =vector<QMesh*>()
SimulationModels	simulationModel =SimulationModels::RIGID_BODY

Detailed Description

QSoftBody is a body type that defines deformable, soft objects in the physics world. Mass-spring model is used for simulation dynamics in soft bodies. In the mass-spring model, there are particles with mass that can move individually and interact with the physics world, and these particles can be connected to each other with spring constraints. Additionally, with some user-configurable options specific to the simulation, particles can be subjected to constraints obtained from some calculations. For example, you can add a constraint that ensures particles remain faithful to their initially defined local positions using the "shape matching" option. You can apply a constraint that gives the feeling that the polygon are filled with gas and maintains their area using the "area preserving" option. You can use options that allow particles to collide with each other with a specific radius, and create objects called PBD (Position Based Dynamics). QSoftBody objects inherently require a more flexible configuration than other body types and contain many options.

Member Function Documentation

ApplyShapeMatching()

void QSoftBody::ApplyShapeMatching

(

)

Applies the shape matching operation to the body.

GetAreaPreservingEnabled()

bool QSoftBody::GetAreaPreservingEnabled ( )

inline

Returns whether the area preserving option is enabled of the body. If the area preserving option is enabled, the total area of the polygon are calculated at each physics step, and forces are applied to the particles that define the boundaries of the polygon to achieve a total area that can be determined by the user. If the user does not specify, when this option is enabled, the target area is calculated based on the original positions of the polygon particles, in other words, the total area of undeformed polygons are set as the target area.

GetAreaPreservingRate()

float QSoftBody::GetAreaPreservingRate ( )

inline

Returns the rate to apply area preserving to the body if the area preserving is enabled. Determines the rate of the target area to apply preserve constraints.

GetAreaPreservingRigidity()

float QSoftBody::GetAreaPreservingRigidity ( )

inline

Returns the rigidity to apply area preserving to the body if the area preserving is enabled. Determines the hardness of the restrictions to be applied to particles for the application of the target area.

GetMass()

float QSoftBody::GetMass ( )

inlinevirtual

Returns mass value of the body.

Reimplemented from QBody.

GetParticleSpesificMass()

float QSoftBody::GetParticleSpesificMass ( )

inline

Returns the particle-specific mass value of the body. This value is used if the particle-specific mass option is enabled.

GetParticleSpesificMassEnabled()

bool QSoftBody::GetParticleSpesificMassEnabled ( )

inline

Sets whether the particle-spesific mass option is enabled for the body. If this option is set to true, particles will continue to move with the mass defined for the body, but a specific mass value provided by you will be used for collision and constraint calculations. In most case, you don't want the mass value defined for the entire soft body object to be used for individual particle collision and constraint responses. Instead, you can define a specific particle mass value by dividing the mass value of the body by the number of particles, for example.

GetPassivationOfInternalSpringsEnabled()

bool QSoftBody::GetPassivationOfInternalSpringsEnabled ( )

inline

Returns whether to passivate the internal spring connections of the soft body. If this option is enabled, the internal springs are more passive in the simulation, which can be useful for soft bodies where the internal springs and particle connections only provide UV and other data based on the movement of the soft body.

GetRigidity()

float QSoftBody::GetRigidity ( )

inline

Returns the rigidity of the body. It determines the rigidity of the spring joints of the body.

GetSelfCollisionsEnabled()

bool QSoftBody::GetSelfCollisionsEnabled ( )

inline

Gets whether self collisions are enabled for the body. If set to true, all mesh parts within the body will collide with each other.

GetSelfCollisionsSpecifiedRadius()

float QSoftBody::GetSelfCollisionsSpecifiedRadius ( )

inline

Returns the specified particle radius value for self particle collisions. If the value is 0.0, particles will collide with their radius. Default value is 0.0.

GetShapeMatchingEnabled()

bool QSoftBody::GetShapeMatchingEnabled ( )

inline

Returns whether the shape matcing option is enabled for the body. If set to true, during the simulation process, all particles are forced to stay true to their undeformed positions.

GetShapeMatchingFixedPosition()

QVector QSoftBody::GetShapeMatchingFixedPosition ( )

inline

Sets the position of the target shape during shape matching if the fixed transform feature is active.

GetShapeMatchingFixedRotation()

float QSoftBody::GetShapeMatchingFixedRotation ( )

inline

Sets the rotation of the target shape during shape matching if the fixed transform feature is active.

GetShapeMatchingFixedTransformEnabled()

bool QSoftBody::GetShapeMatchingFixedTransformEnabled ( )

inline

Returns whether you will be able to determine the position and rotation of the target shape when the shape matching feature is active. If set to true, you will be able to adjust the position and rotation values of the target shape yourself.

GetShapeMatchingRate()

float QSoftBody::GetShapeMatchingRate ( )

inline

Returns the rate value to apply the shape matching to the body.

GetTargetPreservationArea()

float QSoftBody::GetTargetPreservationArea ( )

inline

Returns the total target area to apply area preserving if the area preserving is enabled.

PostUpdate()

void QSoftBody::PostUpdate ( )

virtual

Called after all bodies have completed their Update step to perform post-update operations.

Reimplemented from QBody.

PreserveAreas()

void QSoftBody::PreserveAreas

(

)

Applies the preserve area operation to the body.

SetAreaPreservingEnabled()

QSoftBody* QSoftBody::SetAreaPreservingEnabled ( bool  value )

inline

Sets whether the area preserving option is enabled of the body. If the area preserving option is enabled, the total area of the polygon are calculated at each physics step, and forces are applied to the particles that define the boundaries of the polygon to achieve a total area that can be determined by the user. If the user does not specify, when this option is enabled, the target area is calculated based on the original positions of the polygon particles, in other words, the total area of undeformed polygons are set as the target area.

Parameters

value

A value to set.

Returns

A pointer to the body itself.

SetAreaPreservingRate()

QSoftBody* QSoftBody::SetAreaPreservingRate ( float  value )

inline

Sets the rate to apply area preserving to the body if the area preserving is enabled. Determines the rate of the target area to apply preserve constraints.

Parameters

value

A value to set, it must be a value between 0.0 and 1.0.

Returns

A pointer to the body itself.

SetAreaPreservingRigidity()

QSoftBody* QSoftBody::SetAreaPreservingRigidity ( float  value )

inline

Sets the rigidity to apply area preserving to the body if the area preserving is enabled. Determines the hardness of the restrictions to be applied to particles for the application of the target area.

Parameters

value

A value to set.

Returns

A pointer to the body itself.

SetParticleSpesificMass()

QSoftBody* QSoftBody::SetParticleSpesificMass ( float  value )

inline

Sets the particle-specific mass value of the body. This value is used if the particle-specific mass option is enabled.

Parameters

value

A value to set.

Returns

A pointer to the body itself.

SetParticleSpesificMassEnabled()

QSoftBody* QSoftBody::SetParticleSpesificMassEnabled ( bool  value )

inline

Sets whether the particle-spesific mass option is enabled for the body. If this option is set to true, particles will continue to move with the mass defined for the body, but a specific mass value provided by you will be used for collision and constraint calculations. In most case, you don't want the mass value defined for the entire soft body object to be used for individual particle collision and constraint responses. Instead, you can define a specific particle mass value by dividing the mass value of the body by the number of particles, for example.

Parameters

value

A value to set.

Returns

A pointer to the body itself.

SetPassivationOfInternalSpringsEnabled()

QSoftBody* QSoftBody::SetPassivationOfInternalSpringsEnabled ( bool  value )

inline

Sets whether to passivate the internal spring connections of the soft body. If this option is enabled, the internal springs are more passive in the simulation, which can be useful for soft bodies where the internal springs and particle connections only provide UV and other data based on the movement of the soft body.

Parameters

value

A value to set.

Returns

A pointer to the body itself.

SetRigidity()

QSoftBody* QSoftBody::SetRigidity ( float  value )

inline

Sets the rigidity of the body. It determines the rigidity of the spring joints of the body.

Parameters

value

A value to set.

Returns

A pointer to the body itself.

SetSelfCollisionsEnabled()

QSoftBody* QSoftBody::SetSelfCollisionsEnabled ( bool  value )

inline

Sets whether self particle collisions are enabled for the body. If set to true, all mesh parts within the body will collide with each other.

Parameters

value

A value to set.

Returns

A pointer to the body itself.

SetSelfCollisionsSpecifiedRadius()

QSoftBody* QSoftBody::SetSelfCollisionsSpecifiedRadius ( float  value )

inline

Sets a specified particle radius value for self particle collisions. If set to 0, particles will collide with their radius. Default value is 0.

Parameters

value

A value to set.

Returns

A pointer to the body itself.

SetShapeMatchingEnabled()

QSoftBody* QSoftBody::SetShapeMatchingEnabled ( bool  value, bool  withoutInternals = false  )

inline

Sets whether the shape matcing option is enabled for the body. If set to true, during the simulation process, all particles are forced to stay true to their undeformed positions.

Parameters

value	A value to set.
withoutInternals	Applies method without internal particles.

Returns

A pointer to the body itself.

SetShapeMatchingFixedPosition()

QSoftBody* QSoftBody::SetShapeMatchingFixedPosition ( QVector  value )

inline

Sets the position of the target shape during shape matching if the fixed transform feature is active.

Parameters

value

A value to set.

Returns

A pointer to the body itself.

SetShapeMatchingFixedRotation()

QSoftBody* QSoftBody::SetShapeMatchingFixedRotation ( float  value )

inline

Sets the rotation value of the target shape during shape matching if the fixed transform feature is active.

Parameters

value

A value to set.

Returns

A pointer to the body itself.

SetShapeMatchingFixedTransformEnabled()

QSoftBody* QSoftBody::SetShapeMatchingFixedTransformEnabled ( bool  value )

inline

Sets whether you will be able to determine the position and rotation of the target shape when the shape matching feature is active. If set to true, you will be able to adjust the position and rotation values of the target shape yourself.

Parameters

value

A value to set.

Returns

A pointer to the body itself.

SetShapeMatchingRate()

QSoftBody* QSoftBody::SetShapeMatchingRate ( float  value )

inline

Sets the rate value to apply the shape matching to the body.

Parameters

value

A value to set, it must be a value between 0.0 and 1.0.

Returns

A pointer to the body itself.

SetTargetPreservationArea()

QSoftBody* QSoftBody::SetTargetPreservationArea ( float  value )

inline

Sets the total target area to apply area preserving if the area preserving is enabled.

Parameters

value

A value to set.

Returns

A pointer to the body itself.

Update()

void QSoftBody::Update ( )

virtual

Updates properties of the soft body and applies needed physical dynamics.

Reimplemented from QBody.

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

• QuarkPhysics/qsoftbody.h
• QuarkPhysics/qsoftbody.cpp