Chaos::FSolverBody Class Reference

#include <SolverBody.h>

Public Member Functions
	FSolverBody ()
void	Reset ()
void	SetImplicitVelocity (FReal Dt)
	Calculate and set the velocity and angular velocity from the net transform delta.
FSolverReal	InvM () const
	Get the inverse mass.
void	SetInvM (FReal InInvM)
	Set the inverse mass.
const FSolverMatrix33 &	InvI () const
	Get the world-space inverse inertia.
void	SetInvI (const FMatrix33 &InInvI)
	Set the world-space inverse inertia.
const FSolverVec3 &	InvILocal () const
	Get the local-space inverse inertia (diagonal elements)
void	SetInvILocal (const FVec3 &InInvILocal)
	Set the local-space inverse inertia (diagonal elements)
FRigidTransform3	CoMTransform () const
	The current CoM transform.
const FVec3 &	X () const
	Pre-integration world-space center of mass position.
void	SetX (const FVec3 &InX)
const FRotation3 &	R () const
	Pre-integration world-space center of mass rotation.
void	SetR (const FRotation3 &InR)
const FVec3 &	P () const
	Predicted (post-integrate) world-space center of mass position.
void	SetP (const FVec3 &InP)
const FRotation3 &	Q () const
	Predicted (post-integrate) world-space center of mass rotation.
void	SetQ (const FRotation3 &InQ)
const FSolverVec3 &	V () const
	World-space center of mass velocity.
void	SetV (const FVec3 &InV)
const FSolverVec3 &	W () const
	World-space center of mass angular velocity.
void	SetW (const FVec3 &InW)
const FVec3 &	CoM () const
void	SetCoM (const FVec3 &InCoM)
const FRotation3 &	RoM () const
void	SetRoM (const FRotation3 &InRoM)
const FSolverVec3 &	DP () const
	Net world-space position displacement applied by the constraints.
void	SetDP (const FSolverVec3 &InDP)
const FSolverVec3 &	DQ () const
	Net world-space rotation displacement applied by the constraints (axis-angle vector equivalent to angular velocity but for position)
void	SetDQ (const FSolverVec3 &InDQ)
const FSolverVec3 &	CP () const
	Net world-space position correction applied by the constraints.
const FSolverVec3 &	CQ () const
	Net world-space rotation correction applied by the constraints (axis-angle vector equivalent to angular velocity but for position)
FVec3	CorrectedP () const
	World-space position after applying the net correction DP()
FRotation3	CorrectedQ () const
	World-space rotation after applying the net correction DQ()
void	ApplyCorrections ()
	Apply the accumulated position and rotation corrections to the predicted P and Q This is only used by unit tests that reuse solver bodies between ticks.
FVec3	ActorP () const
	Get the world-space Actor position.
FRotation3	ActorQ () const
	Get the world-space Actor rotation.
FVec3	CorrectedActorP () const
	Get the current world-space Actor position.
FRotation3	CorrectedActorQ () const
	Get the current world-space Actor rotation.
int32	Level () const
	Contact graph level. This is used in shock propagation to determine which of two bodies should have its inverse mass scaled.
void	SetLevel (int32 InLevel)
bool	IsDynamic () const
	Whether the body has a finite mass.
void	ApplyTransformDelta (const FSolverVec3 &DP, const FSolverVec3 &DR)
	Apply a world-space position and rotation delta to the body center of mass, and update inverse mass.
void	ApplyPositionDelta (const FSolverVec3 &DP)
	Apply a world-space position delta to the solver body center of mass.
void	ApplyRotationDelta (const FSolverVec3 &DR)
	Apply a world-space rotation delta to the solver body and update the inverse mass.
void	ApplyPositionCorrectionDelta (const FSolverVec3 &CP)
	Apply a world-space position correction delta to the solver body center of mass This will translate the body without introducing linear velocity.
void	ApplyRotationCorrectionDelta (const FSolverVec3 &CR)
	Apply a world-space rotation correction delta to the solver body This will rotate the body without introducing angular velocity.
void	ApplyVelocityDelta (const FSolverVec3 &DV, const FSolverVec3 &DW)
	Apply a world-space velocity delta to the solver body.
void	ApplyLinearVelocityDelta (const FSolverVec3 &DV)
	Apply a world-space linear velocity delta to the solver body.
void	ApplyAngularVelocityDelta (const FSolverVec3 &DW)
	Apply an world-space angular velocity delta to the solver body.
void	EnforceShortestRotationTo (const FRotation3 &InQ)
	Update the rotation to be in the same hemisphere as the provided quaternion. This is used by joints with angular constraint/drives.
void	UpdateRotationDependentState ()
	Update cached state that depends on rotation (i.e., world space inertia)
void	PrefetchPositionSolverData () const
void	PrefetchVelocitySolverData () const

Static Public Member Functions
static constexpr FSolverReal	ZeroMassThreshold ()
static FSolverBody	MakeInitialized ()
static FSolverBody	MakeUninitialized ()

Detailed Description

Used by the constraint solver loop to cache all state for a particle and accumulate solver results. Uses a gather/scatter mechanism to read/write data to the particle SOAs at the beginning/end of the constraint solve. Constraint solver algorithms, and collision Update functions are implemented to use FSolverBody, and do not directly read/write to the particle handles. Constraint Solvers will modify P(), Q(), V() and W() via ApplyTransformDelta() and other methods.

There is one SolverBody for each particle in an island. Most constraint solvers will actually wrap the FSolverBody in FConstraintSolverBody, which allows us to apply per-constraint modifiers to the Solver Body.

Note

the X(), P(), R(), Q() accessors on FSolverBody return the Center of Mass positions and rotations, in contrast to the Particle methods which gives Actor positions and rotations. This is because the Constraint Solvers all calculate impulses and position corrections relative to the center of mass.

Constructor & Destructor Documentation

FSolverBody()

Chaos::FSolverBody::FSolverBody ( )

inline

Create an empty solver body. All properties are uninitialized.

Member Function Documentation

ActorP()

FVec3 Chaos::FSolverBody::ActorP ( ) const

inline

Get the world-space Actor position.

ActorQ()

FRotation3 Chaos::FSolverBody::ActorQ ( ) const

inline

Get the world-space Actor rotation.

ApplyAngularVelocityDelta()

void Chaos::FSolverBody::ApplyAngularVelocityDelta ( const FSolverVec3 &  DW )

inline

Apply an world-space angular velocity delta to the solver body.

ApplyCorrections()

void Chaos::FSolverBody::ApplyCorrections ( )

inline

Apply the accumulated position and rotation corrections to the predicted P and Q This is only used by unit tests that reuse solver bodies between ticks.

ApplyLinearVelocityDelta()

void Chaos::FSolverBody::ApplyLinearVelocityDelta ( const FSolverVec3 &  DV )

inline

Apply a world-space linear velocity delta to the solver body.

ApplyPositionCorrectionDelta()

void Chaos::FSolverBody::ApplyPositionCorrectionDelta ( const FSolverVec3 &  CP )

inline

Apply a world-space position correction delta to the solver body center of mass This will translate the body without introducing linear velocity.

ApplyPositionDelta()

void Chaos::FSolverBody::ApplyPositionDelta ( const FSolverVec3 &  DP )

inline

Apply a world-space position delta to the solver body center of mass.

ApplyRotationCorrectionDelta()

void Chaos::FSolverBody::ApplyRotationCorrectionDelta ( const FSolverVec3 &  CR )

inline

Apply a world-space rotation correction delta to the solver body This will rotate the body without introducing angular velocity.

ApplyRotationDelta()

void Chaos::FSolverBody::ApplyRotationDelta ( const FSolverVec3 &  DR )

inline

Apply a world-space rotation delta to the solver body and update the inverse mass.

ApplyTransformDelta()

void Chaos::FSolverBody::ApplyTransformDelta ( const FSolverVec3 &  DP, const FSolverVec3 &  DR  )

inline

Apply a world-space position and rotation delta to the body center of mass, and update inverse mass.

ApplyVelocityDelta()

void Chaos::FSolverBody::ApplyVelocityDelta ( const FSolverVec3 &  DV, const FSolverVec3 &  DW  )

inline

Apply a world-space velocity delta to the solver body.

CoM()

const FVec3 & Chaos::FSolverBody::CoM ( ) const

inline

CoMTransform()

FRigidTransform3 Chaos::FSolverBody::CoMTransform ( ) const

inline

The current CoM transform.

CorrectedActorP()

FVec3 Chaos::FSolverBody::CorrectedActorP ( ) const

inline

Get the current world-space Actor position.

Note

This is recalculated from the current CoM transform including the accumulated position and rotation corrections.

CorrectedActorQ()

FRotation3 Chaos::FSolverBody::CorrectedActorQ ( ) const

inline

Get the current world-space Actor rotation.

Note

This is recalculated from the current CoM transform including the accumulated position and rotation corrections.

CorrectedP()

FVec3 Chaos::FSolverBody::CorrectedP ( ) const

inline

World-space position after applying the net correction DP()

Note

Calculated on demand from P() and DP() (only requires vector addition)

CorrectedQ()

FRotation3 Chaos::FSolverBody::CorrectedQ ( ) const

inline

World-space rotation after applying the net correction DQ()

Note

Calculated on demand from Q() and DQ() (requires quaternion multiply and normalization)

CP()

const FSolverVec3 & Chaos::FSolverBody::CP ( ) const

inline

Net world-space position correction applied by the constraints.

Note

This only includes correction terms that do not introduce linear velocity. The full solver displacement is given by DP

CQ()

const FSolverVec3 & Chaos::FSolverBody::CQ ( ) const

inline

Net world-space rotation correction applied by the constraints (axis-angle vector equivalent to angular velocity but for position)

Note

This only includes correction terms that do not introduce angular velocity. The full solver angular displacement is given by DQ

DP()

const FSolverVec3 & Chaos::FSolverBody::DP ( ) const

inline

Net world-space position displacement applied by the constraints.

DQ()

const FSolverVec3 & Chaos::FSolverBody::DQ ( ) const

inline

Net world-space rotation displacement applied by the constraints (axis-angle vector equivalent to angular velocity but for position)

EnforceShortestRotationTo()

void Chaos::FSolverBody::EnforceShortestRotationTo ( const FRotation3 &  InQ )

inline

Update the rotation to be in the same hemisphere as the provided quaternion. This is used by joints with angular constraint/drives.

InvI()

const FSolverMatrix33 & Chaos::FSolverBody::InvI ( ) const

inline

Get the world-space inverse inertia.

InvILocal()

const FSolverVec3 & Chaos::FSolverBody::InvILocal ( ) const

inline

Get the local-space inverse inertia (diagonal elements)

InvM()

FSolverReal Chaos::FSolverBody::InvM ( ) const

inline

Get the inverse mass.

IsDynamic()

bool Chaos::FSolverBody::IsDynamic ( ) const

inline

Whether the body has a finite mass.

Note

This is based on the current inverse mass, so a "dynamic" particle with 0 inverse mass will return true here.

Level()

int32 Chaos::FSolverBody::Level ( ) const

inline

Contact graph level. This is used in shock propagation to determine which of two bodies should have its inverse mass scaled.

MakeInitialized()

static FSolverBody Chaos::FSolverBody::MakeInitialized ( )

inlinestatic

A factory method to create a safely initialized Solverbody. The defaultconstructor assumes you are going to set all properties manually.

MakeUninitialized()

static FSolverBody Chaos::FSolverBody::MakeUninitialized ( )

inlinestatic

Create an empty solver body. All properties are uninitialized.

P()

const FVec3 & Chaos::FSolverBody::P ( ) const

inline

Predicted (post-integrate) world-space center of mass position.

Note

This does not get updated as we iterate

See also

DP(), CorrectedP()

PrefetchPositionSolverData()

void Chaos::FSolverBody::PrefetchPositionSolverData ( ) const

inline

PrefetchVelocitySolverData()

void Chaos::FSolverBody::PrefetchVelocitySolverData ( ) const

inline

Q()

const FRotation3 & Chaos::FSolverBody::Q ( ) const

inline

Predicted (post-integrate) world-space center of mass rotation.

Note

This does not get updated as we iterate

See also

DQ(), CorrectedQ()

R()

const FRotation3 & Chaos::FSolverBody::R ( ) const

inline

Pre-integration world-space center of mass rotation.

Reset()

void Chaos::FSolverBody::Reset ( )

inline

Reset the solver accumulators

RoM()

const FRotation3 & Chaos::FSolverBody::RoM ( ) const

inline

SetCoM()

void Chaos::FSolverBody::SetCoM ( const FVec3 &  InCoM )

inline

SetDP()

void Chaos::FSolverBody::SetDP ( const FSolverVec3 &  InDP )

inline

SetDQ()

void Chaos::FSolverBody::SetDQ ( const FSolverVec3 &  InDQ )

inline

SetImplicitVelocity()

void Chaos::FSolverBody::SetImplicitVelocity ( FReal  Dt )

inline

Calculate and set the velocity and angular velocity from the net transform delta.

SetInvI()

void Chaos::FSolverBody::SetInvI ( const FMatrix33 &  InInvI )

inline

Set the world-space inverse inertia.

SetInvILocal()

void Chaos::FSolverBody::SetInvILocal ( const FVec3 &  InInvILocal )

inline

Set the local-space inverse inertia (diagonal elements)

SetInvM()

void Chaos::FSolverBody::SetInvM ( FReal  InInvM )

inline

Set the inverse mass.

SetLevel()

void Chaos::FSolverBody::SetLevel ( int32  InLevel )

inline

SetP()

void Chaos::FSolverBody::SetP ( const FVec3 &  InP )

inline

SetQ()

void Chaos::FSolverBody::SetQ ( const FRotation3 &  InQ )

inline

SetR()

void Chaos::FSolverBody::SetR ( const FRotation3 &  InR )

inline

SetRoM()

void Chaos::FSolverBody::SetRoM ( const FRotation3 &  InRoM )

inline

SetV()

void Chaos::FSolverBody::SetV ( const FVec3 &  InV )

inline

SetW()

void Chaos::FSolverBody::SetW ( const FVec3 &  InW )

inline

SetX()

void Chaos::FSolverBody::SetX ( const FVec3 &  InX )

inline

UpdateRotationDependentState()

void Chaos::FSolverBody::UpdateRotationDependentState

(

)

Update cached state that depends on rotation (i.e., world space inertia)

V()

const FSolverVec3 & Chaos::FSolverBody::V ( ) const

inline

World-space center of mass velocity.

W()

const FSolverVec3 & Chaos::FSolverBody::W ( ) const

inline

World-space center of mass angular velocity.

X()

const FVec3 & Chaos::FSolverBody::X ( ) const

inline

Pre-integration world-space center of mass position.

ZeroMassThreshold()

static constexpr FSolverReal Chaos::FSolverBody::ZeroMassThreshold ( )

inlinestaticconstexpr

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

• Engine/Source/Runtime/Experimental/Chaos/Public/Chaos/Evolution/SolverBody.h
• Engine/Source/Runtime/Experimental/Chaos/Private/Chaos/Evolution/SolverBody.cpp