#include <EulerSolver.h>

Inheritance diagram for sofa::component::odesolver::forward::EulerExplicitSolver:

Detailed Description

The simplest time integration. Two variants of the Euler solver are available in this component:

forward Euler method, also called explicit Euler method
semi-implicit Euler method, also called semi-explicit Euler method or symplectic Euler

In both variants, acceleration is first computed. The system to compute the acceleration is M * a = f, where M is the mass matrix and f can be a force. In case of a diagonal mass matrix, M is trivially invertible and the acceleration can be computed without a linear solver.

f is accumulated by force fields through the addForce function. Mappings can also contribute by projecting forces of mapped objects. f is computed based on the current state (current velocity and position).

Explicit Euler method: The option "symplectic" must be set to false to use this variant. The explicit Euler method produces an approximate discrete solution by iterating x_{n+1} = x_n + v_n * dt v_{n+1} = v_n + a * dt

Semi-implicit Euler method: The option "symplectic" must be set to true to use this variant. The semi-implicit Euler method produces an approximate discrete solution by iterating v_{n+1} = v_n + a * dt x_{n+1} = x_n + v_{n+1} * dt

The semi-implicit Euler method is more robust than the standard Euler method.

Public Attributes
Data< bool >	d_symplectic
	If true (default), the velocities are updated before the positions and the method is symplectic, more robust. If false, the positions are updated before the velocities (standard Euler, less robust). More...

Data< bool >	d_threadSafeVisitor
	If true, do not use realloc and free visitors in fwdInteractionForceField. More...

SingleLink< EulerExplicitSolver, core::behavior::LinearSolver, BaseLink::FLAG_STRONGLINK >	l_linearSolver

Public Attributes inherited from sofa::core::objectmodel::BaseObject
Data< bool >	f_listening
	if true, handle the events, otherwise ignore the events More...

Public Attributes inherited from sofa::core::objectmodel::Base
std::vector< lifecycle::DeprecatedData * >	m_oldAttributes

Data< int >	d_messageLogCount

Data< std::string >	name
	Name of the object. More...

Data< bool >	f_printLog
	if true, emits extra messages at runtime. More...

Data< sofa::core::objectmodel::TagSet >	f_tags
	list of the subsets the objet belongs to More...

Data< sofa::type::BoundingBox >	f_bbox
	this object bounding box More...

Data< sofa::core::objectmodel::ComponentState >	d_componentState
	The state of the component among (Dirty, Valid, Undefined, Loading, Invalid). More...

std::string	m_definitionSourceFileName {""}

int	m_definitionSourceFilePos {-1}

std::string	m_instanciationSourceFileName {""}

int	m_instanciationSourceFilePos {-1}

Public Member Functions
	SOFA_CLASS (EulerExplicitSolver, sofa::core::behavior::OdeSolver)

void	solve (const core::ExecParams *params, SReal dt, sofa::core::MultiVecCoordId xResult, sofa::core::MultiVecDerivId vResult) override

SReal	getIntegrationFactor (int inputDerivative, int outputDerivative) const override

SReal	getSolutionIntegrationFactor (int outputDerivative) const override

void	init () override
	Initialization method called at graph creation and modification, during top-down traversal. More...

Public Member Functions inherited from sofa::core::behavior::OdeSolver
	SOFA_ABSTRACT_CLASS (OdeSolver, objectmodel::BaseObject)

virtual void	solve (const core::ExecParams *params, SReal dt)

virtual void	computeResidual (const core::ExecParams *, SReal, sofa::core::MultiVecCoordId, sofa::core::MultiVecDerivId)

virtual SReal	getVelocityIntegrationFactor () const

virtual SReal	getPositionIntegrationFactor () const

bool	insertInNode (objectmodel::BaseNode *node) override

bool	removeInNode (objectmodel::BaseNode *node) override

Public Member Functions inherited from sofa::core::objectmodel::BaseObject
	SOFA_CLASS (BaseObject, Base)

virtual void	draw (const core::visual::VisualParams *)
	Render internal data of this object, for debugging purposes. More...

virtual void	computeBBox (const core::ExecParams *, bool=false)

void	setSrc (const std::string &v, std::vector< std::string > *attributeList=nullptr)
	Sets a source Object and parses it to collect dependent Data. More...

void	setSrc (const std::string &v, const BaseObject loader, std::vector< std::string > attributeList=nullptr)

Base *	findLinkDestClass (const BaseClass destType, const std::string &path, const BaseLink link) override

virtual std::string	getPathName () const override
	Return the full path name of this object. More...

SReal	getTime () const
	Current time. More...

const BaseContext *	getContext () const

BaseContext *	getContext ()

const BaseObject *	getMaster () const

BaseObject *	getMaster ()

const VecSlaves &	getSlaves () const

BaseObject *	getSlave (const std::string &name) const

virtual void	addSlave (BaseObject::SPtr s)

virtual void	removeSlave (BaseObject::SPtr s)

virtual void	handleEvent (Event *)
	Handle an event. More...

virtual void	handleTopologyChange ()

virtual void	handleTopologyChange (core::topology::Topology *t)

void	parse (BaseObjectDescription *arg) override
	Parse the given description to assign values to this object's fields and potentially other parameters. More...

virtual void	bwdInit ()
	Initialization method called at graph creation and modification, during bottom-up traversal. More...

virtual void	reinit ()
	Update method called when variables used in precomputation are modified. More...

void	updateInternal ()
	Update method called when variables (used to compute other internal variables) are modified. More...

virtual void	storeResetState ()
	Save the initial state for later uses in reset() More...

virtual void	reset ()
	Reset to initial state. More...

virtual void	cleanup ()

Public Member Functions inherited from sofa::core::objectmodel::Base
virtual const BaseClass *	getClass () const

void	addDeprecatedAttribute (lifecycle::DeprecatedData *attribute)

void	addUpdateCallback (const std::string &name, std::initializer_list< BaseData * > inputs, std::function< sofa::core::objectmodel::ComponentState(const DataTracker &)> function, std::initializer_list< BaseData * > outputs)

void	addOutputsToCallback (const std::string &name, std::initializer_list< BaseData * > outputs)

const std::string &	getName () const
	Accessor to the object name. More...

void	setName (const std::string &n)
	Set the name of this object. More...

void	setName (const std::string &n, int counter)
	Set the name of this object, adding an integer counter. More...

std::string	getTypeName () const
	Get the type name of this object (i.e. class and template types) More...

virtual std::string	getClassName () const
	Get the class name of this object. More...

virtual std::string	getTemplateName () const final
	Get the template type names (if any) used to instantiate this object. More...

std::string	getNameSpaceName () const
	Get the template type names (if any) used to instantiate this object. More...

void	setDefinitionSourceFileName (const std::string &sourceFileName)
	Set the source filename (where the component is implemented) More...

const std::string &	getDefinitionSourceFileName () const
	Get the source filename (where the component is implemented) More...

void	setDefinitionSourceFilePos (const int)
	Set the source location (where the component is implemented) More...

int	getDefinitionSourceFilePos () const
	Get the source location (where the component is implemented) More...

void	setInstanciationSourceFileName (const std::string &sourceFileName)

const std::string &	getInstanciationSourceFileName () const

void	setInstanciationSourceFilePos (const int)

int	getInstanciationSourceFilePos () const

void	addMessage (const sofa::helper::logging::Message &m) const

size_t	countLoggedMessages (sofa::helper::logging::Message::TypeSet t=sofa::helper::logging::Message::AnyTypes) const

const std::deque< sofa::helper::logging::Message > &	getLoggedMessages () const

const std::string	getLoggedMessagesAsString (sofa::helper::logging::Message::TypeSet t=sofa::helper::logging::Message::AnyTypes) const

void	clearLoggedMessages () const

bool	notMuted () const

const sofa::core::objectmodel::TagSet &	getTags () const
	Represents the subsets the object belongs to. More...

bool	hasTag (Tag t) const
	Return true if the object belong to the given subset. More...

void	addTag (Tag t)
	Add a subset qualification to the object. More...

void	removeTag (Tag t)
	Remove a subset qualification to the object. More...

ComponentState	getComponentState () const

bool	isComponentStateValid () const

virtual bool	parseField (const std::string &attribute, const std::string &value)
	Assign one field value (Data or Link) More...

virtual bool	hasField (const std::string &attribute) const
	Check if a given Data field or Link exists. More...

void	parseFields (const std::list< std::string > &str)
	Assign the field values stored in the given list of name + value pairs of strings. More...

virtual void	parseFields (const std::map< std::string, std::string * > &str)
	Assign the field values stored in the given map of name -> value pairs. More...

void	writeDatas (std::map< std::string, std::string * > &str)
	Write the current field values to the given map of name -> value pairs. More...

void	writeDatas (std::ostream &out, const std::string &separator=" ")

BaseData *	findData (const std::string &name) const

std::vector< BaseData * >	findGlobalField (const std::string &name) const
	Find data fields given a name: several can be found as we look into the alias map. More...

BaseLink *	findLink (const std::string &name) const

std::vector< BaseLink * >	findLinks (const std::string &name) const
	Find link fields given a name: several can be found as we look into the alias map. More...

virtual void	updateLinks (bool logErrors=true)
	Update pointers in case the pointed-to objects have appeared. More...

template<class T >
BaseData::BaseInitData	initData (::sofa::core::objectmodel::Data< T > field, const char name, const char *help, ::sofa::core::objectmodel::BaseData::DataFlags dataflags)
	Helper method used to initialize a data field containing a value of type T. More...

template<class T >
BaseData::BaseInitData	initData (Data< T > field, const char name, const char *help, bool isDisplayed=true, bool isReadOnly=false)
	Helper method used to initialize a data field containing a value of type T. More...

template<class T >
Data< T >::InitData	initData (Data< T > field, const T &value, const char name, const char *help, bool isDisplayed=true, bool isReadOnly=false)
	Helper method used to initialize a data field containing a value of type T. More...

void	addData (BaseData *f, const std::string &name)

void	addData (BaseData *f)

void	removeData (BaseData *f)
	Remove a data field. More...

void	addAlias (BaseData field, const char alias)
	Add an alias to a Data. More...

void	addLink (BaseLink *l)
	Add a link. More...

void	addAlias (BaseLink link, const char alias)
	Add an alias to a Link. More...

const VecData &	getDataFields () const
	Accessor to the vector containing all the fields of this object. More...

const MapData &	getDataAliases () const
	Accessor to the map containing all the aliases of this object. More...

const VecLink &	getLinks () const
	Accessor to the vector containing all the fields of this object. More...

const MapLink &	getLinkAliases () const
	Accessor to the map containing all the aliases of this object. More...

virtual bool	findDataLinkDest (BaseData &ptr, const std::string &path, const BaseLink link)

template<class T >
bool	findLinkDest (T &ptr, const std::string &path, const BaseLink link)

Protected Member Functions
	EulerExplicitSolver ()

void	updateState (sofa::simulation::common::VectorOperations vop, sofa::simulation::common::MechanicalOperations mop, sofa::core::MultiVecCoordId xResult, sofa::core::MultiVecDerivId vResult, const sofa::core::behavior::MultiVecDeriv &acc, SReal dt) const

void	assembleSystemMatrix (sofa::simulation::common::MechanicalOperations *mop) const

void	solveSystem (core::MultiVecDerivId solution, core::MultiVecDerivId rhs) const

Protected Member Functions inherited from sofa::core::behavior::OdeSolver
	OdeSolver ()

	~OdeSolver () override

Protected Member Functions inherited from sofa::core::objectmodel::BaseObject
	BaseObject ()

	~BaseObject () override

virtual void	doUpdateInternal ()
	Implementation of the internal update. More...

void	changeContextLink (BaseContext before, BaseContext &after)

void	changeSlavesLink (BaseObject::SPtr ptr, std::size_t, bool add)
	This method insures that slaves objects have master and context links set correctly. More...

void	trackInternalData (const BaseData &data)
	Method called to add the Data to the DataTracker (listing the Data to track) More...

void	cleanTracker ()

bool	hasDataChanged (const BaseData &data)
	Method called to know if a tracked Data has changed. More...

Protected Member Functions inherited from sofa::core::objectmodel::Base
	Base ()

virtual	~Base ()

void	initData0 (BaseData field, BaseData::BaseInitData &res, const char name, const char *help, bool isDisplayed=true, bool isReadOnly=false)
	Helper method used by initData() More...

void	initData0 (BaseData field, BaseData::BaseInitData &res, const char name, const char *help, BaseData::DataFlags dataFlags)
	Helper method used by initData() More...

template<class T >
void	initData0 (Data< T > field, typename Data< T >::InitData &res, const T &value, const char name, const char *help, bool isDisplayed=true, bool isReadOnly=false)
	Helper method used by initData() More...

Static Protected Member Functions
static void	addSeparateGravity (sofa::simulation::common::MechanicalOperations *mop, SReal dt, core::MultiVecDerivId v)

static void	computeForce (sofa::simulation::common::MechanicalOperations *mop, core::MultiVecDerivId f)
	Assemble the force vector (right-hand side of the equation) More...

static void	computeAcceleration (sofa::simulation::common::MechanicalOperations *mop, core::MultiVecDerivId acc, core::ConstMultiVecDerivId f)

static void	projectResponse (sofa::simulation::common::MechanicalOperations *mop, core::MultiVecDerivId vecId)
	Apply projective constraints, such as FixedProjectiveConstraint. More...

static void	solveConstraints (sofa::simulation::common::MechanicalOperations *mop, core::MultiVecDerivId acc)

Additional Inherited Members
Protected Attributes inherited from sofa::core::objectmodel::BaseObject
SingleLink< BaseObject, BaseContext, BaseLink::FLAG_DOUBLELINK >	l_context

LinkSlaves	l_slaves

SingleLink< BaseObject, BaseObject, BaseLink::FLAG_DOUBLELINK >	l_master

Protected Attributes inherited from sofa::core::objectmodel::Base
std::map< std::string, sofa::core::DataTrackerCallback >	m_internalEngine

VecData	m_vecData
	List of fields (Data instances) More...

MapData	m_aliasData
	name -> Data multi-map (includes names and aliases) More...

VecLink	m_vecLink
	List of links. More...

MapLink	m_aliasLink
	name -> Link multi-map (includes names and aliases) More...

Static Public Member Functions inherited from sofa::core::objectmodel::BaseObject
template<class T >
static bool	canCreate (T , BaseContext , BaseObjectDescription *)
	Pre-construction check method called by ObjectFactory. More...

template<class T >
static T::SPtr	create (T , BaseContext context, BaseObjectDescription *arg)
	Construction method called by ObjectFactory. More...

Static Public Member Functions inherited from sofa::core::objectmodel::Base
static const BaseClass *	GetClass ()

template<class T >
static std::string	shortName (const T ptr=nullptr, BaseObjectDescription =nullptr)

Attribute details

◆ d_symplectic

Data<bool> sofa::component::odesolver::forward::EulerExplicitSolver::d_symplectic

If true (default), the velocities are updated before the positions and the method is symplectic, more robust. If false, the positions are updated before the velocities (standard Euler, less robust).

◆ d_threadSafeVisitor

Data<bool> sofa::component::odesolver::forward::EulerExplicitSolver::d_threadSafeVisitor

If true, do not use realloc and free visitors in fwdInteractionForceField.

◆ l_linearSolver

SingleLink<EulerExplicitSolver, core::behavior::LinearSolver, BaseLink::FLAG_STRONGLINK> sofa::component::odesolver::forward::EulerExplicitSolver::l_linearSolver

Constructor details

◆ EulerExplicitSolver()

sofa::component::odesolver::forward::EulerExplicitSolver::EulerExplicitSolver ( )

protected

Function details

◆ addSeparateGravity()

void sofa::component::odesolver::forward::EulerExplicitSolver::addSeparateGravity	(	sofa::simulation::common::MechanicalOperations *	mop,
		SReal	dt,
		core::MultiVecDerivId	v
	)

staticprotected

Gravity times time step size is added to the velocity for some masses v += g * dt

◆ assembleSystemMatrix()

void sofa::component::odesolver::forward::EulerExplicitSolver::assembleSystemMatrix ( sofa::simulation::common::MechanicalOperations * mop ) const

protected

◆ computeAcceleration()

void sofa::component::odesolver::forward::EulerExplicitSolver::computeAcceleration	(	sofa::simulation::common::MechanicalOperations *	mop,
		core::MultiVecDerivId	acc,
		core::ConstMultiVecDerivId	f
	)

staticprotected

Compute the acceleration from the force and the inverse of the mass acc = M^-1 * f

◆ computeForce()

void sofa::component::odesolver::forward::EulerExplicitSolver::computeForce	(	sofa::simulation::common::MechanicalOperations *	mop,
		core::MultiVecDerivId	f
	)

staticprotected

Assemble the force vector (right-hand side of the equation)

◆ getIntegrationFactor()

SReal sofa::component::odesolver::forward::EulerExplicitSolver::getIntegrationFactor	(	int	inputDerivative,
		int	outputDerivative
	)		const

overridevirtual

Given an input derivative order (0 for position, 1 for velocity, 2 for acceleration), how much will it affect the output derivative of the given order.

Reimplemented from sofa::core::behavior::OdeSolver.

◆ getSolutionIntegrationFactor()

SReal sofa::component::odesolver::forward::EulerExplicitSolver::getSolutionIntegrationFactor ( int outputDerivative ) const

overridevirtual

Given a solution of the linear system, how much will it affect the output derivative of the given order.

Reimplemented from sofa::core::behavior::OdeSolver.

◆ init()

void sofa::component::odesolver::forward::EulerExplicitSolver::init ( void )

overridevirtual

Initialization method called at graph creation and modification, during top-down traversal.

Reimplemented from sofa::core::objectmodel::BaseObject.

◆ projectResponse()

void sofa::component::odesolver::forward::EulerExplicitSolver::projectResponse	(	sofa::simulation::common::MechanicalOperations *	mop,
		core::MultiVecDerivId	vecId
	)

staticprotected

Apply projective constraints, such as FixedProjectiveConstraint.

◆ SOFA_CLASS()

sofa::component::odesolver::forward::EulerExplicitSolver::SOFA_CLASS	(	EulerExplicitSolver	,
		sofa::core::behavior::OdeSolver
	)

◆ solve()

void sofa::component::odesolver::forward::EulerExplicitSolver::solve	(	const core::ExecParams *	,
		SReal	,
		sofa::core::MultiVecCoordId	,
		sofa::core::MultiVecDerivId
	)

overridevirtual

Main computation method.

Specify and execute all computation for timestep integration, i.e. advancing the state from time t to t+dt, putting the resulting position and velocity in the provided vectors.

Implements sofa::core::behavior::OdeSolver.

◆ solveConstraints()

void sofa::component::odesolver::forward::EulerExplicitSolver::solveConstraints	(	sofa::simulation::common::MechanicalOperations *	mop,
		core::MultiVecDerivId	acc
	)

staticprotected

◆ solveSystem()

void sofa::component::odesolver::forward::EulerExplicitSolver::solveSystem	(	core::MultiVecDerivId	solution,
		core::MultiVecDerivId	rhs
	)		const

protected

◆ updateState()

void sofa::component::odesolver::forward::EulerExplicitSolver::updateState	(	sofa::simulation::common::VectorOperations *	vop,
		sofa::simulation::common::MechanicalOperations *	mop,
		sofa::core::MultiVecCoordId	xResult,
		sofa::core::MultiVecDerivId	vResult,
		const sofa::core::behavior::MultiVecDeriv &	acc,
		SReal	dt
	)		const

protected

Update state variable (new position and velocity) based on the computed acceleration The update takes constraints into account

Detailed Description

Public Attributes

Public Member Functions

Protected Member Functions

Static Protected Member Functions

Additional Inherited Members

Attribute details

◆ d_symplectic

◆ d_threadSafeVisitor

◆ l_linearSolver

Constructor details

◆ EulerExplicitSolver()

Function details

◆ addSeparateGravity()

◆ assembleSystemMatrix()

◆ computeAcceleration()

◆ computeForce()

◆ getIntegrationFactor()

◆ getSolutionIntegrationFactor()

◆ init()

◆ projectResponse()

◆ SOFA_CLASS()

◆ solve()

◆ solveConstraints()

◆ solveSystem()

◆ updateState()