Represents a Lie group and its associated Lie algebra, i.e. More...

#include <aikido/statespace/StateSpace.hpp>

Inheritance diagram for aikido::statespace::StateSpace:

Classes
class	State

Public Types
using	StateHandle = statespace::StateHandle< StateSpace, State >

using	StateHandleConst = statespace::StateHandle< StateSpace, const State >

using	ScopedState = statespace::ScopedState< StateHandle >

using	ScopedStateConst = statespace::ScopedState< StateHandleConst >

Public Member Functions
virtual	~StateSpace ()=default

ScopedState	createState () const
	Helper function to create a `ScopedState`. More...

ScopedState	cloneState (const State *stateIn) const
	Creates an identical clone of `stateIn`. More...

virtual State *	allocateState () const
	Allocate a new state. More...

virtual void	freeState (State *_state) const
	Free a state previously created by `allocateState`. More...

virtual std::size_t	getStateSizeInBytes () const =0
	Gets the size of a State, in bytes. More...

virtual State *	allocateStateInBuffer (void *_buffer) const =0
	Create a new state in a pre-allocated buffer. More...

virtual void	freeStateInBuffer (State *_state) const =0
	Free a state previously created by `allocateStateInBuffer`. More...

virtual void	compose (const State _state1, const State _state2, State *_out) const =0
	Lie group operation for this StateSpace. More...

virtual void	compose (State _state1, const State _state2) const
	Lie group operation for this StateSpace. More...

virtual void	getIdentity (State *_out) const =0
	Gets the identity element for this Lie group, such that: More...

virtual void	getInverse (const State _state, State _out) const =0
	Gets the inverse of `_in` in this Lie group, such that: More...

virtual void	getInverse (State *_state) const
	Gets the inverse of `_in` in this Lie group. More...

virtual std::size_t	getDimension () const =0
	Get the dimension of this Lie group. More...

virtual void	copyState (const StateSpace::State _source, StateSpace::State _destination) const =0
	Copy a state. More...

virtual void	expMap (const Eigen::VectorXd &_tangent, State *_out) const =0
	Exponential mapping of Lie algebra element to a Lie group element. More...

virtual void	logMap (const State *_in, Eigen::VectorXd &_tangent) const =0
	Log mapping of Lie group element to a Lie algebra element. More...

virtual void	print (const State *_state, std::ostream &_os) const =0
	Print the state to the output stream. More...

Detailed Description

Represents a Lie group and its associated Lie algebra, i.e.

a differentiable manifold embedded in Euclidean space. This is a base class for all other state spaces and provides the following operations:

a group operation
an identity element
an inverse operation
the log map from an element of the Lie group to the Lie algebra
the exponential map from an element of the Lie algebra to the Lie group

These operations on StateSpace are only defined on on State objects created by the same StateSpace instance. State is an opaque class that can only be modified if you know which concrete type of StateSpace created it. We strongly recommend using the ScopedState and StateHandle mechanism to keep each State paired with the StateSpace that it resides in.

Member Typedef Documentation

◆ ScopedState

using aikido::statespace::StateSpace::ScopedState = statespace::ScopedState<StateHandle>

◆ ScopedStateConst

using aikido::statespace::StateSpace::ScopedStateConst = statespace::ScopedState<StateHandleConst>

◆ StateHandle

using aikido::statespace::StateSpace::StateHandle = statespace::StateHandle<StateSpace, State>

◆ StateHandleConst

using aikido::statespace::StateSpace::StateHandleConst = statespace::StateHandle<StateSpace, const State>

Constructor & Destructor Documentation

◆ ~StateSpace()

virtual aikido::statespace::StateSpace::~StateSpace ( )

virtualdefault

Member Function Documentation

◆ allocateState()

virtual State* aikido::statespace::StateSpace::allocateState ( ) const

virtual

Allocate a new state.

This must be deleted with freeState. This is a helper function that allocates memory, uses allocateStateInBuffer to create a State, and returns that pointer.

Returns: state in this space

◆ allocateStateInBuffer()

virtual State* aikido::statespace::StateSpace::allocateStateInBuffer ( void * _buffer ) const

pure virtual

Create a new state in a pre-allocated buffer.

The input argument must contain at least getStateSizeInBytes() bytes of memory. This state must be freed with freeStateInBuffer before freeing _buffer.

Parameters

_buffer memory used to store the returned state

Returns: state object allocated in _buffer

Implemented in aikido::statespace::SO2, aikido::statespace::CartesianProduct, aikido::statespace::R< N >, aikido::statespace::SE2, aikido::statespace::SE3, and aikido::statespace::SO3.

◆ cloneState()

ScopedState aikido::statespace::StateSpace::cloneState ( const State * stateIn ) const

Creates an identical clone of stateIn.

◆ compose() [1/2]

virtual void aikido::statespace::StateSpace::compose	(	const State *	_state1,
		const State *	_state2,
		State *	_out
	)		const

pure virtual

Lie group operation for this StateSpace.

It is not acceptable for _out to share memory with _state1 or _state2.

Parameters

	_state1	left input state
	_state2	right input state
[out]	_out	output state

Implemented in aikido::statespace::SO2, aikido::statespace::CartesianProduct, aikido::statespace::R< N >, aikido::statespace::SE2, aikido::statespace::SE3, and aikido::statespace::SO3.

◆ compose() [2/2]

virtual void aikido::statespace::StateSpace::compose	(	State *	_state1,
		const State *	_state2
	)		const

virtual

Lie group operation for this StateSpace.

This is an in-place version of the three argument compose member function that computes:

_state1 = _state1 * _state2.

Parameters

[in,out]	_state1	left input state, overwritten by output
	_state2	right input state

◆ copyState()

virtual void aikido::statespace::StateSpace::copyState	(	const StateSpace::State *	_source,
		StateSpace::State *	_destination
	)		const

pure virtual

Copy a state.

Parameters

	_source	input state
[out]	_destination	output state

Implemented in aikido::statespace::SO2, aikido::statespace::CartesianProduct, aikido::statespace::R< N >, aikido::statespace::SE2, aikido::statespace::SE3, and aikido::statespace::SO3.

◆ createState()

ScopedState aikido::statespace::StateSpace::createState ( ) const

Helper function to create a ScopedState.

Returns: new ScopedState

◆ expMap()

virtual void aikido::statespace::StateSpace::expMap	(	const Eigen::VectorXd &	_tangent,
		State *	_out
	)		const

pure virtual

Exponential mapping of Lie algebra element to a Lie group element.

The parameterization of the tangent space is defined by the concrete implementation of this class.

Parameters

	_tangent	corresponding element of the tangent space
[out]	_out	element of this Lie group

Implemented in aikido::statespace::SO2, aikido::statespace::CartesianProduct, aikido::statespace::R< N >, aikido::statespace::SE2, aikido::statespace::SE3, and aikido::statespace::SO3.

◆ freeState()

virtual void aikido::statespace::StateSpace::freeState ( State * _state ) const

virtual

Free a state previously created by allocateState.

It is undefined behavior to access _state after calling this function.

Parameters

_state state to be deleted

◆ freeStateInBuffer()

virtual void aikido::statespace::StateSpace::freeStateInBuffer ( State * _state ) const

pure virtual

Free a state previously created by allocateStateInBuffer.

It is undefined behavior to access _state after calling this function.

Parameters

_state state to free

Implemented in aikido::statespace::SO2, aikido::statespace::CartesianProduct, aikido::statespace::R< N >, aikido::statespace::SE2, aikido::statespace::SE3, and aikido::statespace::SO3.

◆ getDimension()

virtual std::size_t aikido::statespace::StateSpace::getDimension ( ) const

pure virtual

Get the dimension of this Lie group.

This is also the dimension of the tangent space, i.e. the Lie algebra, associated with this group.

Returns: dimension of this state space

Implemented in aikido::statespace::CartesianProduct, aikido::statespace::R< N >, aikido::statespace::SE2, aikido::statespace::SE3, aikido::statespace::SO3, and aikido::statespace::SO2.

◆ getIdentity()

virtual void aikido::statespace::StateSpace::getIdentity ( State * _out ) const

pure virtual

Gets the identity element for this Lie group, such that:

compose(state, identity) = state

Parameters

[out] _out output state

Implemented in aikido::statespace::SO2, aikido::statespace::CartesianProduct, aikido::statespace::R< N >, aikido::statespace::SE2, aikido::statespace::SE3, and aikido::statespace::SO3.

◆ getInverse() [1/2]

virtual void aikido::statespace::StateSpace::getInverse	(	const State *	_state,
		State *	_out
	)		const

pure virtual

Gets the inverse of _in in this Lie group, such that:

compose(state, inverse(state)) = identity

It is not acceptable for _in to share memory with _out.

Parameters

	_state	input state
[out]	_out	output state

Implemented in aikido::statespace::SO2, aikido::statespace::CartesianProduct, aikido::statespace::R< N >, aikido::statespace::SE2, aikido::statespace::SE3, and aikido::statespace::SO3.

◆ getInverse() [2/2]

virtual void aikido::statespace::StateSpace::getInverse ( State * _state ) const

virtual

Gets the inverse of _in in this Lie group.

This is an in-place version of the two-argument getInverse member function.

Parameters

[in,out] _state input state, to be overwritten by output

◆ getStateSizeInBytes()

virtual std::size_t aikido::statespace::StateSpace::getStateSizeInBytes ( ) const

pure virtual

Gets the size of a State, in bytes.

Returns: size, in bytes, requires to store a State

Implemented in aikido::statespace::CartesianProduct, aikido::statespace::R< N >, aikido::statespace::SE2, aikido::statespace::SE3, aikido::statespace::SO3, and aikido::statespace::SO2.

◆ logMap()

virtual void aikido::statespace::StateSpace::logMap	(	const State *	_in,
		Eigen::VectorXd &	_tangent
	)		const

pure virtual

Log mapping of Lie group element to a Lie algebra element.

The parameterization of the tangent space is defined by the concrete implementation of this class.

Parameters

	_in	element of this Lie group
[out]	_tangent	corresponding element of the tangent space

Implemented in aikido::statespace::SO2, aikido::statespace::SE2, aikido::statespace::CartesianProduct, aikido::statespace::R< N >, aikido::statespace::SE3, and aikido::statespace::SO3.

◆ print()

virtual void aikido::statespace::StateSpace::print	(	const State *	_state,
		std::ostream &	_os
	)		const

pure virtual

Print the state to the output stream.

Parameters

_state	The element to print
_os	The stream to print to

Implemented in aikido::statespace::SO2, aikido::statespace::CartesianProduct, aikido::statespace::R< N >, aikido::statespace::SE3, aikido::statespace::SE2, and aikido::statespace::SO3.

Classes

Public Types

Public Member Functions

Detailed Description

Member Typedef Documentation

◆ ScopedState

◆ ScopedStateConst

◆ StateHandle

◆ StateHandleConst

Constructor & Destructor Documentation

◆ ~StateSpace()

Member Function Documentation

◆ allocateState()

◆ allocateStateInBuffer()

◆ cloneState()

◆ compose() [1/2]

◆ compose() [2/2]

◆ copyState()

◆ createState()

◆ expMap()

◆ freeState()

◆ freeStateInBuffer()

◆ getDimension()

◆ getIdentity()

◆ getInverse() [1/2]

◆ getInverse() [2/2]

◆ getStateSizeInBytes()

◆ logMap()

◆ print()