QParticle Class Reference

QParticle objects form the network structures of QMesh objects defined for all body object types. They are the smallest building blocks of physics simulation and are manipulated differently in different body object types. For example, in QRigidBody objects, particles are collectively forced into positions obtained through various calculations based on the current body properties. However, in soft body objects, simulation particles are individually manipulated and can move freely, determining the next steps of the simulation through their individual movements. QMesh objects offer a number of methods to manage particles. For more information on restrictions between particles in soft body objects, see the QSpring object. More...

#include <qparticle.h>

Public Member Functions
	QParticle (float posX, float posY, float radius=0.5f)
	QParticle (QVector pos, float radius=0.5f)
QVector	GetGlobalPosition ()
QVector	GetPreviousGlobalPosition ()
QVector	GetPosition ()
float	GetMass ()
QMesh *	GetOwnerMesh ()
float	GetRadius ()
bool	GetIsInternal ()
QVector	GetForce ()
bool	GetEnabled ()
bool	GetIsLazy ()
QAABB	GetAABB ()
QParticle *	SetGlobalPosition (QVector value)
QParticle *	AddGlobalPosition (QVector value)
QParticle *	SetPreviousGlobalPosition (QVector value)
QParticle *	AddPreviousGlobalPosition (QVector value)
QParticle *	SetPosition (QVector value)
QParticle *	AddPosition (QVector value)
QParticle *	SetMass (float value)
QParticle *	SetOwnerMesh (QMesh *mesh)
QParticle *	SetRadius (float radius)
QParticle *	SetIsInternal (bool value)
QParticle *	SetEnabled (bool value)
QParticle *	SetIsLazy (bool value)
QParticle *	ApplyForce (QVector value)
QParticle *	SetForce (QVector value)
QParticle *	AddForce (QVector value)
QParticle *	AddAccumulatedForce (QVector value)
QParticle *	ClearAccumulatedForces ()
QParticle *	ApplyAccumulatedForces ()
bool	IsConnectedWithSpring (QParticle *particle)

Static Public Member Functions
static void	ApplyForceToParticleSegment (QParticle *pA, QParticle *pB, QVector force, QVector fromPosition)
static bool	SortParticlesHorizontal (QParticle *pA, QParticle *pB)

Public Attributes
bool	manualDeletion =false

Protected Member Functions
void	ResetOneTimeCollisions ()
void	UpdateAABB ()

Protected Attributes
std::unordered_set< QParticle * >	springConnectedParticles
unordered_set< QBody * >	oneTimeCollidedBodies
unordered_set< QBody * >	previousCollidedBodies
bool	ignoreGravity =false

Friends
class	QMesh
class	QBody
class	QManifold
class	QAreaBody
class	QCollision

Detailed Description

QParticle objects form the network structures of QMesh objects defined for all body object types. They are the smallest building blocks of physics simulation and are manipulated differently in different body object types. For example, in QRigidBody objects, particles are collectively forced into positions obtained through various calculations based on the current body properties. However, in soft body objects, simulation particles are individually manipulated and can move freely, determining the next steps of the simulation through their individual movements. QMesh objects offer a number of methods to manage particles. For more information on restrictions between particles in soft body objects, see the QSpring object.

Member Function Documentation

AddAccumulatedForce()

QParticle * QParticle::AddAccumulatedForce

(

QVector

value

)

Adds a new force to the accumulated forces. The purpose of the accumulated forces is to apply their arithmetic average using ApplyAccumulatedForce(). Before performing operations with the accumulated forces, they must be cleared using ClearAccumulatedForce().

Parameters

value

A value to add.

Returns

A pointer to the particle itself.

AddForce()

QParticle * QParticle::AddForce

(

QVector

value

)

Adds a value to the force of the particle.Set forces determine the force to be applied to a particle object at the next physics step from the current step.

Parameters

value

A value to add.

Returns

A pointer to the particle itself.

AddGlobalPosition()

QParticle * QParticle::AddGlobalPosition

(

QVector

value

)

Adds a value to the global position of the particle.

Parameters

value

A position value to set.

Returns

A pointer to the particle itself.

AddPosition()

QParticle * QParticle::AddPosition

(

QVector

value

)

Adds a value to the local position of the particle.

Parameters

value

A value to add.

Returns

A pointer to the particle itself.

AddPreviousGlobalPosition()

QParticle * QParticle::AddPreviousGlobalPosition

(

QVector

value

)

Adds a value to the previous global position of the particle.

Parameters

value

A value to add.

Returns

A pointer to the particle itself.

ApplyAccumulatedForces()

QParticle * QParticle::ApplyAccumulatedForces

(

)

Calculates the arithmetic average of the accumulated forces based on the number of forces, applies it to the particle, and then clears all forces.

ApplyForce()

QParticle * QParticle::ApplyForce

(

QVector

value

)

Applies a force immediately to the particle. You can use the method safely before the physics step (e.g. at the OnPreStep event of QBody objects). If you want to use this method after physics step, it can break the simulation.(Collisions and constraints may not be applied properly.) if you want to apply force at the next physic step safely, use SetForce() and AddForce() methods.

Parameters

value

A force value to apply.

ApplyForceToParticleSegment()

void QParticle::ApplyForceToParticleSegment ( QParticle *  pA, QParticle *  pB, QVector  force, QVector  fromPosition  )

static

Applies a specified force to a segment created by two particles at a specific position.

Parameters

pA	A particle in the world.
pB	Another particle in the world.
force	A force value to apply.
fromPosition	The position of the force.

ClearAccumulatedForces()

QParticle * QParticle::ClearAccumulatedForces

(

)

Clears the accumulated forces. It should be called before working with accumulated forces. Additionally, the accumulated forces are automatically cleared after the ApplyAccumulatedForce() method is called.

GetAABB()

QAABB QParticle::GetAABB ( )

inline

Returns the AABB of the particle.

GetEnabled()

bool QParticle::GetEnabled ( )

inline

Returns whether the particle is enabled. Disabled particles are not exempt from the collision tests that involve the meshes they belong to, but the solutions of their manifolds are not applied. Additionally, in body types where particles can move freely individually (e.g., QSoftBody), force and velocity integrations are not applied.

Note

Disabled particles in QRigidBody objects may appear to move because they are transformed based on the position and rotation of the rigid body.

GetForce()

QVector QParticle::GetForce ( )

inline

Returns the current force value of the particle.

GetGlobalPosition()

QVector QParticle::GetGlobalPosition ( )

inline

Returns the global position of the particle.

GetIsInternal()

bool QParticle::GetIsInternal ( )

inline

Returns whether the particle is internal. Internal particle definition is used not for the particles that define the collision boundaries of a mesh, but for the grid particles inside these boundaries. This feature is important for simulation types that require different internal particle simulation, such as volume preserved soft bodies.

GetIsLazy()

bool QParticle::GetIsLazy ( )

inline

Returns whether the particle's lazy feature is enabled. This feature allows the particle to react once in a one-sided manner when colliding with an object; after that, it won't react again until it exits and re-enters the collision. This feature is used for particles that lightly interact with surrounding objects when necessary.

GetMass()

float QParticle::GetMass ( )

inline

Returns the mass of the particle.

GetOwnerMesh()

QMesh* QParticle::GetOwnerMesh ( )

inline

Returns owner mesh of the particle. The Owner mesh is the mesh in which the particle is appointed.

GetPosition()

QVector QParticle::GetPosition ( )

inline

Returns the local position of the particle.

GetPreviousGlobalPosition()

QVector QParticle::GetPreviousGlobalPosition ( )

inline

Returns the previous global position of the particle.

GetRadius()

float QParticle::GetRadius ( )

inline

Returns the radius of the particle.

IsConnectedWithSpring()

bool QParticle::IsConnectedWithSpring

(

QParticle *

particle

)

Checks if the given particle is connected to this particle via a spring. Returns true if a connection exists, otherwise returns false.

Parameters

particle

A particle to check

Returns

Returns true if a connection exists, otherwise returns false.

SetEnabled()

QParticle * QParticle::SetEnabled

(

bool

value

)

Sets whether the particle is enabled. Disabled particles are not exempt from the collision tests that involve the meshes they belong to, but the solutions of their manifolds are not applied. Additionally, in body types where particles can move freely individually (e.g., QSoftBody), force and velocity integrations are not applied.

Note

Disabled particles in QRigidBody objects may appear to move because they are transformed based on the position and rotation of the rigid body.

Parameters

value

A value to set.

Returns

A pointer to the particle itself.

SetForce()

QParticle * QParticle::SetForce

(

QVector

value

)

Sets the force value of the particle. Set forces determine the force to be applied to a particle object at the next physics step from the current step.

Parameters

value

A value to set.

Returns

A pointer to the particle itself.

SetGlobalPosition()

QParticle * QParticle::SetGlobalPosition

(

QVector

value

)

Sets the global position of the particle.

Parameters

value

A position value to set.

Returns

A pointer to the particle itself.

SetIsInternal()

QParticle * QParticle::SetIsInternal

(

bool

value

)

Sets whether the particle is internal.Internal particle definition is used not for the particles that define the collision boundaries of a mesh, but for the grid particles inside these boundaries. This feature is important for simulation types that require different internal particle simulation, such as volume preserved soft bodies.

Parameters

value

True or false.

Returns

A pointer to the particle itself.

SetIsLazy()

QParticle * QParticle::SetIsLazy

(

bool

value

)

Sets whether the particle's lazy feature is enabled. This feature allows the particle to react once in a one-sided manner when colliding with an object; after that, it won't react again until it exits and re-enters the collision. This feature is used for particles that lightly interact with surrounding objects when necessary.

Parameters

value

A value to set.

Returns

A pointer to the particle itself.

SetMass()

QParticle * QParticle::SetMass

(

float

value

)

Sets the mass of the particle.

Parameters

value

A value to set.

Returns

A pointer to the particle itself.

SetOwnerMesh()

QParticle * QParticle::SetOwnerMesh

(

QMesh *

mesh

)

Sets the owner mesh of the particle. Usually the owner mesh is defining when a particle added to a mesh.

Parameters

mesh	A pointer of the mesh to set.

Returns

A pointer to the particle itself.

SetPosition()

QParticle * QParticle::SetPosition

(

QVector

value

)

Sets local position of the particle.

Parameters

value

A value to set.

Returns

A pointer to the particle itself.

SetPreviousGlobalPosition()

QParticle * QParticle::SetPreviousGlobalPosition

(

QVector

value

)

Sets the previous global position of the particle.

Parameters

value

A position value to set.

Returns

A pointer to the particle itself.

SetRadius()

QParticle * QParticle::SetRadius

(

float

radius

)

Sets the radius of the particle.

Parameters

radius

A value to set.

Returns

A pointer to the particle itself.

Member Data Documentation

manualDeletion

bool QParticle::manualDeletion =false

By default, objects included in the physics engine are deleted by the destructors of the objects they belong to. When this flag is enabled, it indicates that this object should never be deleted by this engine. It is disabled by default, and it is recommended to keep it disabled. However, it can be used if needed for advanced purposes and integrations.

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

• QuarkPhysics/qparticle.h
• QuarkPhysics/qparticle.cpp