Description

Class representing the interface for containers of proximity pairs, that is pairs of collision models that have been obtained from the broadphase collision.

There might be implementations of this interface in form of plain CPU linked lists of objects (ex. springs or similar forcefields for cloth simulation etc.) or highly optimized GPU buffers, etc. etc. This is only the basic interface with the features that are in common.

#include <ChProximityContainer.h>

Inheritance diagram for chrono::ChProximityContainer:

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Collaboration diagram for chrono::ChProximityContainer:

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Classes
class	AddProximityCallback
	Class to be used as a callback interface for some user defined action to be taken each time a proximity info is added to the container. More...

class	ReportProximityCallback
	Class to be used as a callback interface for some user defined action to be taken for each proximity pair (already added to the container). More...

Public Member Functions
	ChProximityContainer (const ChProximityContainer &other)

virtual int	GetNproximities () const =0
	Tell the number of added proximity pairs. To be implemented by child classes.

virtual void	RemoveAllProximities ()=0
	Remove (delete) all contained proximity pairs. To be implemented by child classes.

virtual void	BeginAddProximities ()
	The collision system will call BeginAddProximity() before adding all proximity pairs (for example with AddProximity() or similar). More...

virtual void	AddProximity (collision::ChCollisionModel modA, collision::ChCollisionModel modB)=0
	Add a proximity pair between two collision models, storing it into this container. More...

virtual void	EndAddProximities ()
	The collision system will call this after adding all pairs (for example with AddProximity() or similar). More...

void	RegisterAddProximityCallback (AddProximityCallback *mcallback)
	Specify a callback object to be used each time a proximity pair is added to the container. More...

virtual void	ReportAllProximities (ReportProximityCallback *mcallback)=0
	Scans all the proximity pairs and, for each pair, executes the OnReportProximity() function of the provided callback object. More...

virtual void	ArchiveOUT (ChArchiveOut &marchive)
	Method to allow serialization of transient data to archives.

virtual void	ArchiveIN (ChArchiveIn &marchive)
	Method to allow de-serialization of transient data from archives.

Public Member Functions inherited from chrono::ChPhysicsItem
	ChPhysicsItem (const ChPhysicsItem &other)

virtual ChPhysicsItem *	Clone () const override
	"Virtual" copy constructor (covariant return type).

ChSystem *	GetSystem () const
	Get the pointer to the parent ChSystem()

virtual void	SetSystem (ChSystem *m_system)
	Set the pointer to the parent ChSystem() and also add to new collision system / remove from old coll.system.

void	AddAsset (std::shared_ptr< ChAsset > masset)
	Add an optional asset (it can be used to define visualization shapes, es ChSphereShape, or textures, or custom attached properties that the user can define by creating his class inherited from ChAsset)

std::vector< std::shared_ptr< ChAsset > > &	GetAssets ()
	Access to the list of optional assets.

std::shared_ptr< ChAsset >	GetAssetN (unsigned int num)
	Access the Nth asset in the list of optional assets.

virtual ChFrame	GetAssetsFrame (unsigned int nclone=0)
	Get the master coordinate system for assets that have some geometric meaning. More...

virtual unsigned int	GetAssetsFrameNclones ()
	Optionally, a ChPhysicsItem can return multiple asset coordinate systems; this can be helpful if, for example, when a ChPhysicsItem contains 'clones' with the same assets (ex. More...

virtual bool	GetCollide () const
	Tell if the object is subject to collision. More...

virtual void	SyncCollisionModels ()
	If this physical item contains one or more collision models, synchronize their coordinates and bounding boxes to the state of the item.

virtual void	AddCollisionModelsToSystem ()
	If this physical item contains one or more collision models, add them to the system's collision engine.

virtual void	RemoveCollisionModelsFromSystem ()
	If this physical item contains one or more collision models, remove them from the system's collision engine.

virtual void	GetTotalAABB (ChVector<> &bbmin, ChVector<> &bbmax)
	Get the entire AABB axis-aligned bounding box of the object. More...

virtual void	GetCenter (ChVector<> &mcenter)
	Get a symbolic 'center' of the object. More...

virtual void	StreamINstate (ChStreamInBinary &mstream)
	Method to deserialize only the state (position, speed) Must be implemented by child classes.

virtual void	StreamOUTstate (ChStreamOutBinary &mstream)
	Method to serialize only the state (position, speed) Must be implemented by child classes.

virtual void	Setup ()
	This might recompute the number of coordinates, DOFs, constraints, in case this might change (ex in ChAssembly), as well as state offsets of contained items (ex in ChMesh)

virtual void	Update (double mytime, bool update_assets=true)
	This is an important function, which is called by the owner ChSystem at least once per integration step. More...

virtual void	Update (bool update_assets=true)
	As above, but does not require updating of time-dependent data. More...

virtual void	SetNoSpeedNoAcceleration ()
	Set zero speed (and zero accelerations) in state, without changing the position. More...

virtual int	GetDOF ()
	Get the number of scalar coordinates (variables), if any, in this item. More...

virtual int	GetDOF_w ()
	Get the number of scalar coordinates of variables derivatives (usually = DOF, but might be different than DOF, ex. More...

virtual int	GetDOC ()
	Get the number of scalar constraints, if any, in this item.

virtual int	GetDOC_c ()
	Get the number of scalar constraints, if any, in this item (only bilateral constr.) Children classes might override this.

virtual int	GetDOC_d ()
	Get the number of scalar constraints, if any, in this item (only unilateral constr.) Children classes might override this.

unsigned int	GetOffset_x ()
	Get offset in the state vector (position part)

unsigned int	GetOffset_w ()
	Get offset in the state vector (speed part)

unsigned int	GetOffset_L ()
	Get offset in the lagrangian multipliers.

void	SetOffset_x (const unsigned int moff)
	Set offset in the state vector (position part) Note: only the ChSystem::Setup function should use this.

void	SetOffset_w (const unsigned int moff)
	Set offset in the state vector (speed part) Note: only the ChSystem::Setup function should use this.

void	SetOffset_L (const unsigned int moff)
	Set offset in the lagrangian multipliers Note: only the ChSystem::Setup function should use this.

virtual void	IntStateGather (const unsigned int off_x, ChState &x, const unsigned int off_v, ChStateDelta &v, double &T)
	From item's state to global state vectors y={x,v} pasting the states at the specified offsets. More...

virtual void	IntStateScatter (const unsigned int off_x, const ChState &x, const unsigned int off_v, const ChStateDelta &v, const double T, bool full_update)
	From global state vectors y={x,v} to item's state (and update) fetching the states at the specified offsets. More...

virtual void	IntStateGatherAcceleration (const unsigned int off_a, ChStateDelta &a)
	From item's state acceleration to global acceleration vector. More...

virtual void	IntStateScatterAcceleration (const unsigned int off_a, const ChStateDelta &a)
	From global acceleration vector to item's state acceleration. More...

virtual void	IntStateGatherReactions (const unsigned int off_L, ChVectorDynamic<> &L)
	From item's reaction forces to global reaction vector. More...

virtual void	IntStateScatterReactions (const unsigned int off_L, const ChVectorDynamic<> &L)
	From global reaction vector to item's reaction forces. More...

virtual void	IntStateIncrement (const unsigned int off_x, ChState &x_new, const ChState &x, const unsigned int off_v, const ChStateDelta &Dv)
	Computes x_new = x + Dt , using vectors at specified offsets. More...

virtual void	IntLoadResidual_F (const unsigned int off, ChVectorDynamic<> &R, const double c)
	Takes the F force term, scale and adds to R at given offset: R += c*F. More...

virtual void	IntLoadResidual_Mv (const unsigned int off, ChVectorDynamic<> &R, const ChVectorDynamic<> &w, const double c)
	Takes the Mv term, multiplying mass by a vector, scale and adds to R at given offset: R += cM*w. More...

virtual void	IntLoadResidual_CqL (const unsigned int off_L, ChVectorDynamic<> &R, const ChVectorDynamic<> &L, const double c)
	Takes the term Cq'L, scale and adds to R at given offset: R += cCq'*L. More...

virtual void	IntLoadConstraint_C (const unsigned int off, ChVectorDynamic<> &Qc, const double c, bool do_clamp, double recovery_clamp)
	Takes the term C, scale and adds to Qc at given offset: Qc += c*C. More...

virtual void	IntLoadConstraint_Ct (const unsigned int off, ChVectorDynamic<> &Qc, const double c)
	Takes the term Ct, scale and adds to Qc at given offset: Qc += c*Ct. More...

virtual void	IntToDescriptor (const unsigned int off_v, const ChStateDelta &v, const ChVectorDynamic<> &R, const unsigned int off_L, const ChVectorDynamic<> &L, const ChVectorDynamic<> &Qc)
	Prepare variables and constraints to accommodate a solution: More...

virtual void	IntFromDescriptor (const unsigned int off_v, ChStateDelta &v, const unsigned int off_L, ChVectorDynamic<> &L)
	After a solver solution, fetch values from variables and constraints into vectors: More...

virtual void	VariablesFbReset ()
	Sets the 'fb' part (the known term) of the encapsulated ChVariables to zero.

virtual void	VariablesFbLoadForces (double factor=1)
	Adds the current forces (applied to item) into the encapsulated ChVariables, in the 'fb' part: qf+=forces*factor.

virtual void	VariablesQbLoadSpeed ()
	Initialize the 'qb' part of the ChVariables with the current value of speeds. More...

virtual void	VariablesFbIncrementMq ()
	Adds M*q (masses multiplied current 'qb') to Fb, ex. More...

virtual void	VariablesQbSetSpeed (double step=0)
	Fetches the item speed (ex. More...

virtual void	VariablesQbIncrementPosition (double step)
	Increment item positions by the 'qb' part of the ChVariables, multiplied by a 'step' factor. More...

virtual void	InjectVariables (ChSystemDescriptor &mdescriptor)
	Tell to a system descriptor that there are variables of type ChVariables in this object (for further passing it to a solver) Basically does nothing, but maybe that inherited classes may specialize this.

virtual void	InjectConstraints (ChSystemDescriptor &mdescriptor)
	Tell to a system descriptor that there are constraints of type ChConstraint in this object (for further passing it to a solver) Basically does nothing, but maybe that inherited classes may specialize this.

virtual void	ConstraintsBiReset ()
	Sets to zero the known term (b_i) of encapsulated ChConstraints.

virtual void	ConstraintsBiLoad_C (double factor=1, double recovery_clamp=0.1, bool do_clamp=false)
	Adds the current C (constraint violation) to the known term (b_i) of encapsulated ChConstraints.

virtual void	ConstraintsBiLoad_Ct (double factor=1)
	Adds the current Ct (partial t-derivative, as in C_dt=0-> [Cq]*q_dt=-Ct) to the known term (b_i) of encapsulated ChConstraints.

virtual void	ConstraintsBiLoad_Qc (double factor=1)
	Adds the current Qc (the vector of C_dtdt=0 -> [Cq]*q_dtdt=Qc ) to the known term (b_i) of encapsulated ChConstraints.

virtual void	ConstraintsFbLoadForces (double factor=1)
	Adds the current link-forces, if any, (caused by springs, etc.) to the 'fb' vectors of the ChVariables referenced by encapsulated ChConstraints.

virtual void	ConstraintsLoadJacobians ()
	Adds the current jacobians in encapsulated ChConstraints.

virtual void	ConstraintsFetch_react (double factor=1)
	Fetches the reactions from the lagrangian multiplier (l_i) of encapsulated ChConstraints. More...

virtual void	InjectKRMmatrices (ChSystemDescriptor &mdescriptor)
	Tell to a system descriptor that there are items of type ChKblock in this object (for further passing it to a solver) Basically does nothing, but maybe that inherited classes may specialize this.

virtual void	KRMmatricesLoad (double Kfactor, double Rfactor, double Mfactor)
	Adds the current stiffness K and damping R and mass M matrices in encapsulated ChKblock item(s), if any. More...

Public Member Functions inherited from chrono::ChObj
	ChObj (const ChObj &other)

int	GetIdentifier () const
	Gets the numerical identifier of the object.

void	SetIdentifier (int id)
	Sets the numerical identifier of the object.

double	GetChTime () const
	Gets the simulation time of this object.

void	SetChTime (double m_time)
	Sets the simulation time of this object.

const char *	GetName () const
	Gets the name of the object as C Ascii null-terminated string -for reading only!

void	SetName (const char myname[])
	Sets the name of this object, as ascii string.

std::string	GetNameString () const
	Gets the name of the object as C Ascii null-terminated string.

void	SetNameString (const std::string &myname)
	Sets the name of this object, as std::string.

void	MFlagsSetAllOFF (int &mflag)

void	MFlagsSetAllON (int &mflag)

void	MFlagSetON (int &mflag, int mask)

void	MFlagSetOFF (int &mflag, int mask)

int	MFlagGet (int &mflag, int mask)

virtual std::string &	ArchiveContainerName ()

Protected Attributes
AddProximityCallback *	add_proximity_callback

ReportProximityCallback *	report_proximity_callback

Protected Attributes inherited from chrono::ChPhysicsItem
ChSystem *	system
	parent system

std::vector< std::shared_ptr< ChAsset > >	assets
	set of assets

unsigned int	offset_x
	offset in vector of state (position part)

unsigned int	offset_w
	offset in vector of state (speed part)

unsigned int	offset_L
	offset in vector of lagrangian multipliers

Protected Attributes inherited from chrono::ChObj
double	ChTime
	the time of simulation for the object

Member Function Documentation

◆ AddProximity()

virtual void chrono::ChProximityContainer::AddProximity	(	collision::ChCollisionModel *	modA,
		collision::ChCollisionModel *	modB
	)

pure virtual

Add a proximity pair between two collision models, storing it into this container.

To be implemented by child classes. Some specialized child classes (ex. one that uses GPU buffers) could implement also other more efficient functions to add many proximity pairs in a batch (so that, for example, a special GPU collision system can exploit it); yet most collision system might still fall back to this function if no other specialized add-functions are found.

Parameters

modA	get contact model 1
modB	get contact model 2

Implemented in chrono::ChProximityContainerMeshless, and chrono::ChProximityContainerSPH.

◆ BeginAddProximities()

virtual void chrono::ChProximityContainer::BeginAddProximities ( )

inlinevirtual

The collision system will call BeginAddProximity() before adding all proximity pairs (for example with AddProximity() or similar).

By default it deletes all previous contacts. Custom more efficient implementations might reuse contacts if possible.

Reimplemented in chrono::ChProximityContainerMeshless, and chrono::ChProximityContainerSPH.

◆ EndAddProximities()

virtual void chrono::ChProximityContainer::EndAddProximities ( )

inlinevirtual

The collision system will call this after adding all pairs (for example with AddProximity() or similar).

By default it does nothing.

Reimplemented in chrono::ChProximityContainerMeshless, and chrono::ChProximityContainerSPH.

◆ RegisterAddProximityCallback()

void chrono::ChProximityContainer::RegisterAddProximityCallback ( AddProximityCallback * mcallback )

inline

Specify a callback object to be used each time a proximity pair is added to the container.

Note that not all derived classes can support this. If supported, the OnAddProximity() method of the provided callback object will be called for each proximity pair as it is created.

◆ ReportAllProximities()

virtual void chrono::ChProximityContainer::ReportAllProximities ( ReportProximityCallback * mcallback )

pure virtual

Scans all the proximity pairs and, for each pair, executes the OnReportProximity() function of the provided callback object.

Derived classes of ChProximityContainer should try to implement this.

Implemented in chrono::ChProximityContainerMeshless, and chrono::ChProximityContainerSPH.

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

/builds/uwsbel/chrono/src/chrono/physics/ChProximityContainer.h
/builds/uwsbel/chrono/src/chrono/physics/ChProximityContainer.cpp