#include <PBDCollisionSolverJacobi.h>

Public Member Functions
	FPBDCollisionSolverJacobi ()

FORCEINLINE_DEBUGGABLE void	Reset ()

FORCEINLINE_DEBUGGABLE void	ResetManifold ()

FORCEINLINE_DEBUGGABLE int32	AddManifoldPoint ()

FORCEINLINE_DEBUGGABLE FSolverReal	StaticFriction () const

FORCEINLINE_DEBUGGABLE FSolverReal	DynamicFriction () const

FORCEINLINE_DEBUGGABLE FSolverReal	VelocityFriction () const

FORCEINLINE_DEBUGGABLE void	SetFriction (const FSolverReal InStaticFriction, const FSolverReal InDynamicFriction, const FSolverReal InVelocityFriction)

FORCEINLINE_DEBUGGABLE void	SetStiffness (const FSolverReal InStiffness)

FORCEINLINE_DEBUGGABLE void	SetSolverBodies (FSolverBody &SolverBody0, FSolverBody &SolverBody1)

FORCEINLINE_DEBUGGABLE int32	NumManifoldPoints () const

FORCEINLINE_DEBUGGABLE FSolverVec3	GetNetPushOut (const int32 ManifoldPointIndex) const

FORCEINLINE_DEBUGGABLE FSolverVec3	GetNetImpulse (const int32 ManifoldPointIndex) const

FORCEINLINE_DEBUGGABLE FSolverReal	GetStaticFrictionRatio (const int32 ManifoldPointIndex) const

FORCEINLINE_DEBUGGABLE void	SetManifoldPoint (const int32 ManifoldPointIndex, const FSolverVec3 &InRelativeContactPosition0, const FSolverVec3 &InRelativeContactPosition1, const FSolverVec3 &InWorldContactNormal, const FSolverVec3 &InWorldContactTangentU, const FSolverVec3 &InWorldContactTangentV, const FSolverReal InWorldContactDeltaNormal, const FSolverReal InWorldContactDeltaTangentU, const FSolverReal InWorldContactDeltaTangentV, const FSolverReal InWorldContactVelocityTargetNormal)

FORCEINLINE_DEBUGGABLE void	InitManifoldPoint (const int32 ManifoldPointIndex, const FSolverVec3 &InRelativeContactPosition0, const FSolverVec3 &InRelativeContactPosition1, const FSolverVec3 &InWorldContactNormal, const FSolverVec3 &InWorldContactTangentU, const FSolverVec3 &InWorldContactTangentV, const FSolverReal InWorldContactDeltaNormal, const FSolverReal InWorldContactDeltaTangentU, const FSolverReal InWorldContactDeltaTangentV, const FSolverReal InWorldContactVelocityTargetNormal)

FORCEINLINE_DEBUGGABLE void	FinalizeManifoldPoint (const int32 ManifoldPointIndex)

FORCEINLINE_DEBUGGABLE FConstraintSolverBody &	SolverBody0 ()
	Get the first (decorated) solver body The decorator add a possible mass scale.

FORCEINLINE_DEBUGGABLE const FConstraintSolverBody &	SolverBody0 () const

FORCEINLINE_DEBUGGABLE FConstraintSolverBody &	SolverBody1 ()
	Get the second (decorated) solver body The decorator add a possible mass scale.

FORCEINLINE_DEBUGGABLE const FConstraintSolverBody &	SolverBody1 () const

void	EnablePositionShockPropagation ()
	Set up the mass scaling for shock propagation, using the position-phase mass scale.

void	EnableVelocityShockPropagation ()
	Set up the mass scaling for shock propagation, using the velocity-phase mass scale.

void	DisableShockPropagation ()
	Disable mass scaling.

FORCEINLINE_DEBUGGABLE bool	SolvePositionNoFriction (const FSolverReal Dt, const FSolverReal MaxPushOut)
	Calculate and apply the position correction for this iteration.

FORCEINLINE_DEBUGGABLE bool	SolvePositionWithFriction (const FSolverReal Dt, const FSolverReal MaxPushOut)

FORCEINLINE_DEBUGGABLE bool	SolveVelocity (const FSolverReal Dt, const bool bApplyDynamicFriction)
	Calculate and apply the velocity correction for this iteration.

Static Public Member Functions
static FPBDCollisionSolverJacobi	MakeInitialized ()

static FPBDCollisionSolverJacobi	MakeUninitialized ()

Static Public Attributes
static const int32	MaxConstrainedBodies = 2

static const int32	MaxPointsPerConstraint = 4

Detailed Description

A Jocobi solver for the contact manifold between two shapes. This solves each manifold point independently and sums and dampens the net impulses before applying to the bodies.

Pros (vs Gauss Seidel):

If the contacts are symmetric, the impusles will be too. This fixed spurious rotations when a box with high restitution bounces exactly flat on the ground.
We can run the points in the manifold in parallel
Stacking is much more stable (but see below) Cons
We overestimate the impulse and must apply a damping factor to prevent energy gain. It is not clear how we select the value of this damping - it is empirically tuned.
The damping factor leads to spongey stacks/piles

Constructor & Destructor Documentation

◆ FPBDCollisionSolverJacobi()

Chaos::Private::FPBDCollisionSolverJacobi::FPBDCollisionSolverJacobi ( )

inline

Member Function Documentation

◆ AddManifoldPoint()

FORCEINLINE_DEBUGGABLE int32 Chaos::Private::FPBDCollisionSolverJacobi::AddManifoldPoint ( )

inline

◆ DisableShockPropagation()

void Chaos::Private::FPBDCollisionSolverJacobi::DisableShockPropagation ( )

Disable mass scaling.

◆ DynamicFriction()

FORCEINLINE_DEBUGGABLE FSolverReal Chaos::Private::FPBDCollisionSolverJacobi::DynamicFriction ( ) const

inline

◆ EnablePositionShockPropagation()

void Chaos::Private::FPBDCollisionSolverJacobi::EnablePositionShockPropagation ( )

Set up the mass scaling for shock propagation, using the position-phase mass scale.

◆ EnableVelocityShockPropagation()

void Chaos::Private::FPBDCollisionSolverJacobi::EnableVelocityShockPropagation ( )

Set up the mass scaling for shock propagation, using the velocity-phase mass scale.

◆ FinalizeManifoldPoint()

FORCEINLINE_DEBUGGABLE void Chaos::Private::FPBDCollisionSolverJacobi::FinalizeManifoldPoint ( const int32 ManifoldPointIndex )

inline

Finish manifold point setup. NOTE: Can only be called after the InitManifoldPoint has been called

◆ GetNetImpulse()

FORCEINLINE_DEBUGGABLE FSolverVec3 Chaos::Private::FPBDCollisionSolverJacobi::GetNetImpulse ( const int32 ManifoldPointIndex ) const

inline

◆ GetNetPushOut()

FORCEINLINE_DEBUGGABLE FSolverVec3 Chaos::Private::FPBDCollisionSolverJacobi::GetNetPushOut ( const int32 ManifoldPointIndex ) const

inline

◆ GetStaticFrictionRatio()

FORCEINLINE_DEBUGGABLE FSolverReal Chaos::Private::FPBDCollisionSolverJacobi::GetStaticFrictionRatio ( const int32 ManifoldPointIndex ) const

inline

◆ InitManifoldPoint()

FORCEINLINE_DEBUGGABLE void Chaos::Private::FPBDCollisionSolverJacobi::InitManifoldPoint	(	const int32	ManifoldPointIndex,
		const FSolverVec3 &	InRelativeContactPosition0,
		const FSolverVec3 &	InRelativeContactPosition1,
		const FSolverVec3 &	InWorldContactNormal,
		const FSolverVec3 &	InWorldContactTangentU,
		const FSolverVec3 &	InWorldContactTangentV,
		const FSolverReal	InWorldContactDeltaNormal,
		const FSolverReal	InWorldContactDeltaTangentU,
		const FSolverReal	InWorldContactDeltaTangentV,
		const FSolverReal	InWorldContactVelocityTargetNormal
	)

inline

◆ MakeInitialized()

static FPBDCollisionSolverJacobi Chaos::Private::FPBDCollisionSolverJacobi::MakeInitialized ( )

inlinestatic

◆ MakeUninitialized()

static FPBDCollisionSolverJacobi Chaos::Private::FPBDCollisionSolverJacobi::MakeUninitialized ( )

inlinestatic

◆ NumManifoldPoints()

FORCEINLINE_DEBUGGABLE int32 Chaos::Private::FPBDCollisionSolverJacobi::NumManifoldPoints ( ) const

inline

◆ Reset()

FORCEINLINE_DEBUGGABLE void Chaos::Private::FPBDCollisionSolverJacobi::Reset ( )

inline

Reset the state of the collision solver

◆ ResetManifold()

FORCEINLINE_DEBUGGABLE void Chaos::Private::FPBDCollisionSolverJacobi::ResetManifold ( )

inline

◆ SetFriction()

FORCEINLINE_DEBUGGABLE void Chaos::Private::FPBDCollisionSolverJacobi::SetFriction	(	const FSolverReal	InStaticFriction,
		const FSolverReal	InDynamicFriction,
		const FSolverReal	InVelocityFriction
	)

inline

◆ SetManifoldPoint()

FORCEINLINE_DEBUGGABLE void Chaos::Private::FPBDCollisionSolverJacobi::SetManifoldPoint	(	const int32	ManifoldPointIndex,
		const FSolverVec3 &	InRelativeContactPosition0,
		const FSolverVec3 &	InRelativeContactPosition1,
		const FSolverVec3 &	InWorldContactNormal,
		const FSolverVec3 &	InWorldContactTangentU,
		const FSolverVec3 &	InWorldContactTangentV,
		const FSolverReal	InWorldContactDeltaNormal,
		const FSolverReal	InWorldContactDeltaTangentU,
		const FSolverReal	InWorldContactDeltaTangentV,
		const FSolverReal	InWorldContactVelocityTargetNormal
	)

inline

Set up a manifold point (also calls FinalizeManifoldPoint)

◆ SetSolverBodies()

FORCEINLINE_DEBUGGABLE void Chaos::Private::FPBDCollisionSolverJacobi::SetSolverBodies	(	FSolverBody &	SolverBody0,
		FSolverBody &	SolverBody1
	)

inline

◆ SetStiffness()

FORCEINLINE_DEBUGGABLE void Chaos::Private::FPBDCollisionSolverJacobi::SetStiffness ( const FSolverReal InStiffness )

inline

◆ SolvePositionNoFriction()

FORCEINLINE_DEBUGGABLE bool Chaos::Private::FPBDCollisionSolverJacobi::SolvePositionNoFriction	(	const FSolverReal	Dt,
		const FSolverReal	MaxPushOut
	)

inline

Calculate and apply the position correction for this iteration.

Returns: true if we need to run more iterations, false if we did not apply any correction

◆ SolvePositionWithFriction()

FORCEINLINE_DEBUGGABLE bool Chaos::Private::FPBDCollisionSolverJacobi::SolvePositionWithFriction	(	const FSolverReal	Dt,
		const FSolverReal	MaxPushOut
	)

inline

◆ SolverBody0() [1/2]

FORCEINLINE_DEBUGGABLE FConstraintSolverBody & Chaos::Private::FPBDCollisionSolverJacobi::SolverBody0 ( )

inline

Get the first (decorated) solver body The decorator add a possible mass scale.

◆ SolverBody0() [2/2]

FORCEINLINE_DEBUGGABLE const FConstraintSolverBody & Chaos::Private::FPBDCollisionSolverJacobi::SolverBody0 ( ) const

inline

◆ SolverBody1() [1/2]

FORCEINLINE_DEBUGGABLE FConstraintSolverBody & Chaos::Private::FPBDCollisionSolverJacobi::SolverBody1 ( )

inline

Get the second (decorated) solver body The decorator add a possible mass scale.

◆ SolverBody1() [2/2]

FORCEINLINE_DEBUGGABLE const FConstraintSolverBody & Chaos::Private::FPBDCollisionSolverJacobi::SolverBody1 ( ) const

inline

◆ SolveVelocity()

FORCEINLINE_DEBUGGABLE bool Chaos::Private::FPBDCollisionSolverJacobi::SolveVelocity	(	const FSolverReal	Dt,
		const bool	bApplyDynamicFriction
	)

inline

Calculate and apply the velocity correction for this iteration.

Returns: true if we need to run more iterations, false if we did not apply any correction

◆ StaticFriction()

FORCEINLINE_DEBUGGABLE FSolverReal Chaos::Private::FPBDCollisionSolverJacobi::StaticFriction ( ) const

inline

◆ VelocityFriction()

FORCEINLINE_DEBUGGABLE FSolverReal Chaos::Private::FPBDCollisionSolverJacobi::VelocityFriction ( ) const

inline

Member Data Documentation

◆ MaxConstrainedBodies

const int32 Chaos::Private::FPBDCollisionSolverJacobi::MaxConstrainedBodies = 2

static

◆ MaxPointsPerConstraint

const int32 Chaos::Private::FPBDCollisionSolverJacobi::MaxPointsPerConstraint = 4

static

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

Engine/Source/Runtime/Experimental/Chaos/Public/Chaos/Collision/PBDCollisionSolverJacobi.h
Engine/Source/Runtime/Experimental/Chaos/Private/Chaos/Collision/PBDCollisionSolverJacobi.cpp

Public Member Functions

Static Public Member Functions

Static Public Attributes

Detailed Description

Constructor & Destructor Documentation

◆ FPBDCollisionSolverJacobi()

Member Function Documentation

◆ AddManifoldPoint()

◆ DisableShockPropagation()

◆ DynamicFriction()

◆ EnablePositionShockPropagation()

◆ EnableVelocityShockPropagation()

◆ FinalizeManifoldPoint()

◆ GetNetImpulse()

◆ GetNetPushOut()

◆ GetStaticFrictionRatio()

◆ InitManifoldPoint()

◆ MakeInitialized()

◆ MakeUninitialized()

◆ NumManifoldPoints()

◆ Reset()

◆ ResetManifold()

◆ SetFriction()

◆ SetManifoldPoint()

◆ SetSolverBodies()

◆ SetStiffness()

◆ SolvePositionNoFriction()

◆ SolvePositionWithFriction()

◆ SolverBody0() [1/2]

◆ SolverBody0() [2/2]

◆ SolverBody1() [1/2]

◆ SolverBody1() [2/2]

◆ SolveVelocity()

◆ StaticFriction()

◆ VelocityFriction()

Member Data Documentation

◆ MaxConstrainedBodies

◆ MaxPointsPerConstraint