tf::Transformer Class Reference

A Class which provides coordinate transforms between any two frames in a system. More...

#include <tf.h>

Inheritance diagram for tf::Transformer:

Public Member Functions
boost::signals::connection	addTransformsChangedListener (boost::function< void(void)> callback)
	Add a callback that happens when a new transform has arrived.
std::string	allFramesAsDot () const
	A way to see what frames have been cached Useful for debugging.
std::string	allFramesAsString () const
	A way to see what frames have been cached Useful for debugging.
bool	canTransform (const std::string &target_frame, const ros::Time &target_time, const std::string &source_frame, const ros::Time &source_time, const std::string &fixed_frame, std::string *error_msg=NULL) const
	Test if a transform is possible.
bool	canTransform (const std::string &target_frame, const std::string &source_frame, const ros::Time &time, std::string *error_msg=NULL) const
	Test if a transform is possible.
std::string	chainAsString (const std::string &target_frame, ros::Time target_time, const std::string &source_frame, ros::Time source_time, const std::string &fixed_frame) const
	Debugging function that will print the spanning chain of transforms. Possible exceptions tf::LookupException, tf::ConnectivityException, tf::MaxDepthException.
void	chainAsVector (const std::string &target_frame, ros::Time target_time, const std::string &source_frame, ros::Time source_time, const std::string &fixed_frame, std::vector< std::string > &output) const
	Debugging function that will print the spanning chain of transforms. Possible exceptions tf::LookupException, tf::ConnectivityException, tf::MaxDepthException.
void	clear ()
	Clear all data.
bool	frameExists (const std::string &frame_id_str) const
	Check if a frame exists in the tree.
ros::Duration	getCacheLength ()
	Get the duration over which this transformer will cache.
void	getFrameStrings (std::vector< std::string > &ids) const
	A way to get a std::vector of available frame ids.
int	getLatestCommonTime (const std::string &source, const std::string &dest, ros::Time &time, std::string *error_string) const
	Return the latest rostime which is common across the spanning set zero if fails to cross.
bool	getParent (const std::string &frame_id, ros::Time time, std::string &parent) const
	Fill the parent of a frame.
std::string	getTFPrefix () const
	Get the tf_prefix this is running with.
bool	isUsingDedicatedThread ()
void	lookupTransform (const std::string &target_frame, const ros::Time &target_time, const std::string &source_frame, const ros::Time &source_time, const std::string &fixed_frame, StampedTransform &transform) const
	Get the transform between two frames by frame ID assuming fixed frame.
void	lookupTransform (const std::string &target_frame, const std::string &source_frame, const ros::Time &time, StampedTransform &transform) const
	Get the transform between two frames by frame ID.
void	lookupTwist (const std::string &tracking_frame, const std::string &observation_frame, const ros::Time &time, const ros::Duration &averaging_interval, geometry_msgs::Twist &twist) const
	lookup the twist of the tracking frame with respect to the observational frame
void	lookupTwist (const std::string &tracking_frame, const std::string &observation_frame, const std::string &reference_frame, const tf::Point &reference_point, const std::string &reference_point_frame, const ros::Time &time, const ros::Duration &averaging_interval, geometry_msgs::Twist &twist) const
	Lookup the twist of the tracking_frame with respect to the observation frame in the reference_frame using the reference point.
void	removeTransformsChangedListener (boost::signals::connection c)
void	setExtrapolationLimit (const ros::Duration &distance)
	Set the distance which tf is allow to extrapolate.
bool	setTransform (const StampedTransform &transform, const std::string &authority="default_authority")
	Add transform information to the tf data structure.
void	setUsingDedicatedThread (bool value)
	Transformer (bool interpolating=true, ros::Duration cache_time_=ros::Duration(DEFAULT_CACHE_TIME))
void	transformPoint (const std::string &target_frame, const ros::Time &target_time, const Stamped< tf::Point > &stamped_in, const std::string &fixed_frame, Stamped< tf::Point > &stamped_out) const
	Transform a Stamped Point into the target frame This can throw anything a lookupTransform can throw as well as tf::InvalidArgument.
void	transformPoint (const std::string &target_frame, const Stamped< tf::Point > &stamped_in, Stamped< tf::Point > &stamped_out) const
	Transform a Stamped Point into the target frame This can throw anything a lookupTransform can throw as well as tf::InvalidArgument.
void	transformPose (const std::string &target_frame, const ros::Time &target_time, const Stamped< tf::Pose > &stamped_in, const std::string &fixed_frame, Stamped< tf::Pose > &stamped_out) const
	Transform a Stamped Pose into the target frame This can throw anything a lookupTransform can throw as well as tf::InvalidArgument.
void	transformPose (const std::string &target_frame, const Stamped< tf::Pose > &stamped_in, Stamped< tf::Pose > &stamped_out) const
	Transform a Stamped Pose into the target frame This can throw anything a lookupTransform can throw as well as tf::InvalidArgument.
void	transformQuaternion (const std::string &target_frame, const ros::Time &target_time, const Stamped< tf::Quaternion > &stamped_in, const std::string &fixed_frame, Stamped< tf::Quaternion > &stamped_out) const
	Transform a Stamped Quaternion into the target frame This can throw anything a lookupTransform can throw as well as tf::InvalidArgument.
void	transformQuaternion (const std::string &target_frame, const Stamped< tf::Quaternion > &stamped_in, Stamped< tf::Quaternion > &stamped_out) const
	Transform a Stamped Quaternion into the target frame This can throw anything a lookupTransform can throw as well as tf::InvalidArgument.
void	transformVector (const std::string &target_frame, const ros::Time &target_time, const Stamped< tf::Vector3 > &stamped_in, const std::string &fixed_frame, Stamped< tf::Vector3 > &stamped_out) const
	Transform a Stamped Vector3 into the target frame This can throw anything a lookupTransform can throw as well as tf::InvalidArgument.
void	transformVector (const std::string &target_frame, const Stamped< tf::Vector3 > &stamped_in, Stamped< tf::Vector3 > &stamped_out) const
	Transform a Stamped Vector3 into the target frame This can throw anything a lookupTransform can throw as well as tf::InvalidArgument.
bool	waitForTransform (const std::string &target_frame, const ros::Time &target_time, const std::string &source_frame, const ros::Time &source_time, const std::string &fixed_frame, const ros::Duration &timeout, const ros::Duration &polling_sleep_duration=ros::Duration(0.01), std::string *error_msg=NULL) const
	Block until a transform is possible or it times out.
bool	waitForTransform (const std::string &target_frame, const std::string &source_frame, const ros::Time &time, const ros::Duration &timeout, const ros::Duration &polling_sleep_duration=ros::Duration(0.01), std::string *error_msg=NULL) const
	Block until a transform is possible or it times out.
virtual	~Transformer (void)
Public Attributes
bool	fall_back_to_wall_time_
Static Public Attributes
static const double	DEFAULT_CACHE_TIME = 10.0
	The default amount of time to cache data in seconds.
static const int64_t	DEFAULT_MAX_EXTRAPOLATION_DISTANCE = 0ULL
	The default amount of time to extrapolate.
static const unsigned int	MAX_GRAPH_DEPTH = 100UL
	The maximum number of time to recurse before assuming the tree has a loop.
Protected Types
typedef boost::signal< void(void)>	TransformsChangedSignal
Protected Member Functions
btTransform	computeTransformFromList (const TransformLists &list) const
TimeCache *	getFrame (unsigned int frame_number) const
	An accessor to get a frame, which will throw an exception if the frame is no there.
unsigned int	lookupFrameNumber (const std::string &frameid_str) const
	String to number for frame lookup with dynamic allocation of new frames.
std::string	lookupFrameString (unsigned int frame_id_num) const
	Number to string frame lookup may throw LookupException if number invalid.
int	lookupLists (unsigned int target_frame, ros::Time time, unsigned int source_frame, TransformLists &lists, std::string *error_string) const
unsigned int	lookupOrInsertFrameNumber (const std::string &frameid_str)
	String to number for frame lookup with dynamic allocation of new frames.
ros::Time	now () const
virtual bool	ok () const
bool	test_extrapolation (const ros::Time &target_time, const TransformLists &t_lists, std::string *error_string) const
bool	test_extrapolation_future (const ros::Time &target_time, const TransformStorage &tr, std::string *error_string) const
bool	test_extrapolation_one_value (const ros::Time &target_time, const TransformStorage &tr, std::string *error_string) const
bool	test_extrapolation_past (const ros::Time &target_time, const TransformStorage &tr, std::string *error_string) const
Protected Attributes
ros::Duration	cache_time
	How long to cache transform history.
std::map< unsigned int, std::string >	frame_authority_
boost::mutex	frame_mutex_
	A mutex to protect testing and allocating new frames.
std::map< std::string, unsigned int >	frameIDs_
std::vector< std::string >	frameIDs_reverse
std::vector< TimeCache * >	frames_
	The internal storage class for ReferenceTransform.
bool	interpolating
	whether or not to interpolate or extrapolate
ros::Duration	max_extrapolation_distance_
	whether or not to allow extrapolation
std::string	tf_prefix_
	transform prefix to apply as necessary
TransformsChangedSignal	transforms_changed_
	Signal which is fired whenever new transform data has arrived, from the thread the data arrived in.
boost::mutex	transforms_changed_mutex_
bool	using_dedicated_thread_

Detailed Description

A Class which provides coordinate transforms between any two frames in a system.

This class provides a simple interface to allow recording and lookup of relationships between arbitrary frames of the system.

libTF assumes that there is a tree of coordinate frame transforms which define the relationship between all coordinate frames. For example your typical robot would have a transform from global to real world. And then from base to hand, and from base to head. But Base to Hand really is composed of base to shoulder to elbow to wrist to hand. libTF is designed to take care of all the intermediate steps for you.

Internal Representation libTF will store frames with the parameters necessary for generating the transform into that frame from it's parent and a reference to the parent frame. Frames are designated using an std::string 0 is a frame without a parent (the top of a tree) The positions of frames over time must be pushed in.

All function calls which pass frame ids can potentially throw the exception tf::LookupException

Definition at line 85 of file tf.h.

Member Typedef Documentation

typedef boost::signal<void(void)> tf::Transformer::TransformsChangedSignal [protected]

Definition at line 375 of file tf.h.

Constructor & Destructor Documentation

Transformer::Transformer	(	bool	interpolating = `true`,
		ros::Duration	cache_time_ = `ros::Duration(DEFAULT_CACHE_TIME)`
	)

Constructor

Parameters:

	interpolating	Whether to interpolate, if this is false the closest value will be returned
	cache_time	How long to keep a history of transforms in nanoseconds

Definition at line 92 of file tf.cpp.

Transformer::~Transformer ( void ) [virtual]

Definition at line 107 of file tf.cpp.

Member Function Documentation

boost::signals::connection Transformer::addTransformsChangedListener ( boost::function< void(void)> callback )

Add a callback that happens when a new transform has arrived.

Parameters:

callback

The callback, of the form void func();

Returns:: A boost::signals::connection object that can be used to remove this listener

Definition at line 1206 of file tf.cpp.

std::string Transformer::allFramesAsDot ( ) const

A way to see what frames have been cached Useful for debugging.

Definition at line 985 of file tf.cpp.

std::string Transformer::allFramesAsString ( ) const

A way to see what frames have been cached Useful for debugging.

Definition at line 961 of file tf.cpp.

bool Transformer::canTransform	(	const std::string &	target_frame,
		const ros::Time &	target_time,
		const std::string &	source_frame,
		const ros::Time &	source_time,
		const std::string &	fixed_frame,
		std::string *	error_msg = `NULL`
	)			const

Test if a transform is possible.

Parameters:

	target_frame	The frame into which to transform
	target_time	The time into which to transform
	source_frame	The frame from which to transform
	source_time	The time from which to transform
	fixed_frame	The frame in which to treat the transform as constant in time
	error_msg	A pointer to a string which will be filled with why the transform failed, if not NULL

Definition at line 452 of file tf.cpp.

bool Transformer::canTransform	(	const std::string &	target_frame,
		const std::string &	source_frame,
		const ros::Time &	time,
		std::string *	error_msg = `NULL`
	)			const

Test if a transform is possible.

Parameters:

	target_frame	The frame into which to transform
	source_frame	The frame from which to transform
	time	The time at which to transform
	error_msg	A pointer to a string which will be filled with why the transform failed, if not NULL

Todo:: check return

Todo:: WRITE HELPER FUNCITON TO RETHROW

Definition at line 397 of file tf.cpp.

std::string Transformer::chainAsString	(	const std::string &	target_frame,
		ros::Time	target_time,
		const std::string &	source_frame,
		ros::Time	source_time,
		const std::string &	fixed_frame
	)			const

Debugging function that will print the spanning chain of transforms. Possible exceptions tf::LookupException, tf::ConnectivityException, tf::MaxDepthException.

Todo:: check return code

Definition at line 889 of file tf.cpp.

void Transformer::chainAsVector	(	const std::string &	target_frame,
		ros::Time	target_time,
		const std::string &	source_frame,
		ros::Time	source_time,
		const std::string &	fixed_frame,
		std::vector< std::string > &	output
	)			const

Debugging function that will print the spanning chain of transforms. Possible exceptions tf::LookupException, tf::ConnectivityException, tf::MaxDepthException.

Todo:: check return code

Definition at line 920 of file tf.cpp.

void Transformer::clear ( )

Clear all data.

Definition at line 119 of file tf.cpp.

btTransform Transformer::computeTransformFromList ( const TransformLists & list ) const [protected]

Compute the transform based on the list of frames

Todo:: change these to iterators

Definition at line 871 of file tf.cpp.

bool Transformer::frameExists ( const std::string & frame_id_str ) const

Check if a frame exists in the tree.

Parameters:

frame_id_str

The frame id in question

Definition at line 497 of file tf.cpp.

ros::Duration tf::Transformer::getCacheLength ( ) [inline]

Get the duration over which this transformer will cache.

Definition at line 314 of file tf.h.

tf::TimeCache * Transformer::getFrame ( unsigned int frame_number ) const [protected]

An accessor to get a frame, which will throw an exception if the frame is no there.

Parameters:

frame_number

The frameID of the desired Reference Frame

This is an internal function which will get the pointer to the frame associated with the frame id Possible Exception: tf::LookupException

Todo:: check larger values too

Definition at line 1077 of file tf.cpp.

void Transformer::getFrameStrings ( std::vector< std::string > & ids ) const

A way to get a std::vector of available frame ids.

Definition at line 1061 of file tf.cpp.

int Transformer::getLatestCommonTime	(	const std::string &	source,
		const std::string &	dest,
		ros::Time &	time,
		std::string *	error_string
	)			const

Return the latest rostime which is common across the spanning set zero if fails to cross.

Todo:: replace with ros::TIME_MAX when it is merged from stable

Definition at line 516 of file tf.cpp.

bool Transformer::getParent	(	const std::string &	frame_id,
		ros::Time	time,
		std::string &	parent
	)			const

Fill the parent of a frame.

Parameters:

	frame_id	The frame id of the frame in question
	parent	The reference to the string to fill the parent Returns true unless "NO_PARENT"

Definition at line 468 of file tf.cpp.

std::string tf::Transformer::getTFPrefix ( ) const [inline]

Get the tf_prefix this is running with.

Definition at line 329 of file tf.h.

bool tf::Transformer::isUsingDedicatedThread ( ) [inline]

Definition at line 334 of file tf.h.

unsigned int tf::Transformer::lookupFrameNumber ( const std::string & frameid_str ) const [inline, protected]

String to number for frame lookup with dynamic allocation of new frames.

Definition at line 412 of file tf.h.

std::string tf::Transformer::lookupFrameString ( unsigned int frame_id_num ) const [inline, protected]

Number to string frame lookup may throw LookupException if number invalid.

Definition at line 446 of file tf.h.

int Transformer::lookupLists	(	unsigned int	target_frame,
		ros::Time	time,
		unsigned int	source_frame,
		TransformLists &	lists,
		std::string *	error_string
	)			const `[protected]`

Find the list of connected frames necessary to connect two different frames

Todo:: add fixed frame support

Definition at line 563 of file tf.cpp.

unsigned int tf::Transformer::lookupOrInsertFrameNumber ( const std::string & frameid_str ) [inline, protected]

String to number for frame lookup with dynamic allocation of new frames.

Definition at line 429 of file tf.h.

void Transformer::lookupTransform	(	const std::string &	target_frame,
		const ros::Time &	target_time,
		const std::string &	source_frame,
		const ros::Time &	source_time,
		const std::string &	fixed_frame,
		StampedTransform &	transform
	)			const

Get the transform between two frames by frame ID assuming fixed frame.

Parameters:

	target_frame	The frame to which data should be transformed
	target_time	The time to which the data should be transformed. (0 will get the latest)
	source_frame	The frame where the data originated
	source_time	The time at which the source_frame should be evaluated. (0 will get the latest)
	fixed_frame	The frame in which to assume the transform is constant in time.
	transform	The transform reference to fill.

Possible exceptions tf::LookupException, tf::ConnectivityException, tf::MaxDepthException, tf::ExtrapolationException

Definition at line 269 of file tf.cpp.

void Transformer::lookupTransform	(	const std::string &	target_frame,
		const std::string &	source_frame,
		const ros::Time &	time,
		StampedTransform &	transform
	)			const

Get the transform between two frames by frame ID.

Parameters:

	target_frame	The frame to which data should be transformed
	source_frame	The frame where the data originated
	time	The time at which the value of the transform is desired. (0 will get the latest)
	transform	The transform reference to fill.

Possible exceptions tf::LookupException, tf::ConnectivityException, tf::MaxDepthException, tf::ExtrapolationException

Definition at line 192 of file tf.cpp.

void Transformer::lookupTwist	(	const std::string &	tracking_frame,
		const std::string &	observation_frame,
		const ros::Time &	time,
		const ros::Duration &	averaging_interval,
		geometry_msgs::Twist &	twist
	)			const

lookup the twist of the tracking frame with respect to the observational frame

This is a simplified version of lookupTwist with it assumed that the reference point is the origin of the tracking frame, and the reference frame is the observation frame.

New in geometry 1.1

Definition at line 283 of file tf.cpp.

void Transformer::lookupTwist	(	const std::string &	tracking_frame,
		const std::string &	observation_frame,
		const std::string &	reference_frame,
		const tf::Point &	reference_point,
		const std::string &	reference_point_frame,
		const ros::Time &	time,
		const ros::Duration &	averaging_interval,
		geometry_msgs::Twist &	twist
	)			const

Lookup the twist of the tracking_frame with respect to the observation frame in the reference_frame using the reference point.

Parameters:

	tracking_frame	The frame to track
	observation_frame	The frame from which to measure the twist
	reference_frame	The reference frame in which to express the twist
	reference_point	The reference point with which to express the twist
	reference_point_frame	The frame_id in which the reference point is expressed
	time	The time at which to get the velocity
	duration	The period over which to average
	twist	The twist output

This will compute the average velocity on the interval (time - duration/2, time+duration/2). If that is too close to the most recent reading, in which case it will shift the interval up to duration/2 to prevent extrapolation. Possible exceptions tf::LookupException, tf::ConnectivityException, tf::MaxDepthException, tf::ExtrapolationException

New in geometry 1.1

check time on reference point too

Definition at line 292 of file tf.cpp.

ros::Time tf::Transformer::now ( ) const [inline, protected]

Hack method to work around #4150

Definition at line 392 of file tf.h.

bool Transformer::ok ( ) const [protected, virtual]

Reimplemented in tf::TransformListener.

Definition at line 1059 of file tf.cpp.

void Transformer::removeTransformsChangedListener ( boost::signals::connection c )

Definition at line 1212 of file tf.cpp.

void Transformer::setExtrapolationLimit ( const ros::Duration & distance )

Set the distance which tf is allow to extrapolate.

Parameters:

distance

How far to extrapolate before throwing an exception default is zero

Definition at line 511 of file tf.cpp.

bool Transformer::setTransform	(	const StampedTransform &	transform,
		const std::string &	authority = `"default_authority"`
	)

Add transform information to the tf data structure.

Parameters:

	transform	The transform to store
	authority	The source of the information for this transform returns true unless an error occured

Definition at line 132 of file tf.cpp.

void tf::Transformer::setUsingDedicatedThread ( bool value ) [inline]

Definition at line 332 of file tf.h.

bool Transformer::test_extrapolation	(	const ros::Time &	target_time,
		const TransformLists &	t_lists,
		std::string *	error_string
	)			const `[protected]`

Definition at line 848 of file tf.cpp.

bool Transformer::test_extrapolation_future	(	const ros::Time &	target_time,
		const TransformStorage &	tr,
		std::string *	error_string
	)			const `[protected]`

Definition at line 824 of file tf.cpp.

bool Transformer::test_extrapolation_one_value	(	const ros::Time &	target_time,
		const TransformStorage &	tr,
		std::string *	error_string
	)			const `[protected]`

Definition at line 772 of file tf.cpp.

bool Transformer::test_extrapolation_past	(	const ros::Time &	target_time,
		const TransformStorage &	tr,
		std::string *	error_string
	)			const `[protected]`

Definition at line 800 of file tf.cpp.

void Transformer::transformPoint	(	const std::string &	target_frame,
		const ros::Time &	target_time,
		const Stamped< tf::Point > &	stamped_in,
		const std::string &	fixed_frame,
		Stamped< tf::Point > &	stamped_out
	)			const

Transform a Stamped Point into the target frame This can throw anything a lookupTransform can throw as well as tf::InvalidArgument.

Definition at line 1176 of file tf.cpp.

void Transformer::transformPoint	(	const std::string &	target_frame,
		const Stamped< tf::Point > &	stamped_in,
		Stamped< tf::Point > &	stamped_out
	)			const

Transform a Stamped Point into the target frame This can throw anything a lookupTransform can throw as well as tf::InvalidArgument.

Definition at line 1117 of file tf.cpp.

void Transformer::transformPose	(	const std::string &	target_frame,
		const ros::Time &	target_time,
		const Stamped< tf::Pose > &	stamped_in,
		const std::string &	fixed_frame,
		Stamped< tf::Pose > &	stamped_out
	)			const

Transform a Stamped Pose into the target frame This can throw anything a lookupTransform can throw as well as tf::InvalidArgument.

Definition at line 1191 of file tf.cpp.

void Transformer::transformPose	(	const std::string &	target_frame,
		const Stamped< tf::Pose > &	stamped_in,
		Stamped< tf::Pose > &	stamped_out
	)			const

Transform a Stamped Pose into the target frame This can throw anything a lookupTransform can throw as well as tf::InvalidArgument.

Definition at line 1127 of file tf.cpp.

void Transformer::transformQuaternion	(	const std::string &	target_frame,
		const ros::Time &	target_time,
		const Stamped< tf::Quaternion > &	stamped_in,
		const std::string &	fixed_frame,
		Stamped< tf::Quaternion > &	stamped_out
	)			const

Transform a Stamped Quaternion into the target frame This can throw anything a lookupTransform can throw as well as tf::InvalidArgument.

Definition at line 1138 of file tf.cpp.

void Transformer::transformQuaternion	(	const std::string &	target_frame,
		const Stamped< tf::Quaternion > &	stamped_in,
		Stamped< tf::Quaternion > &	stamped_out
	)			const

Transform a Stamped Quaternion into the target frame This can throw anything a lookupTransform can throw as well as tf::InvalidArgument.

Definition at line 1086 of file tf.cpp.

void Transformer::transformVector	(	const std::string &	target_frame,
		const ros::Time &	target_time,
		const Stamped< tf::Vector3 > &	stamped_in,
		const std::string &	fixed_frame,
		Stamped< tf::Vector3 > &	stamped_out
	)			const

Transform a Stamped Vector3 into the target frame This can throw anything a lookupTransform can throw as well as tf::InvalidArgument.

Todo:: may not be most efficient

Definition at line 1155 of file tf.cpp.

void Transformer::transformVector	(	const std::string &	target_frame,
		const Stamped< tf::Vector3 > &	stamped_in,
		Stamped< tf::Vector3 > &	stamped_out
	)			const

Transform a Stamped Vector3 into the target frame This can throw anything a lookupTransform can throw as well as tf::InvalidArgument.

Todo:: may not be most efficient

Definition at line 1099 of file tf.cpp.

bool Transformer::waitForTransform	(	const std::string &	target_frame,
		const ros::Time &	target_time,
		const std::string &	source_frame,
		const ros::Time &	source_time,
		const std::string &	fixed_frame,
		const ros::Duration &	timeout,
		const ros::Duration &	polling_sleep_duration = `ros::Duration(0.01)`,
		std::string *	error_msg = `NULL`
	)			const

Block until a transform is possible or it times out.

Parameters:

	target_frame	The frame into which to transform
	target_time	The time into which to transform
	source_frame	The frame from which to transform
	source_time	The time from which to transform
	fixed_frame	The frame in which to treat the transform as constant in time
	timeout	How long to block before failing
	polling_sleep_duration	How often to retest if failed
	error_msg	A pointer to a string which will be filled with why the transform failed, if not NULL

Definition at line 459 of file tf.cpp.

bool Transformer::waitForTransform	(	const std::string &	target_frame,
		const std::string &	source_frame,
		const ros::Time &	time,
		const ros::Duration &	timeout,
		const ros::Duration &	polling_sleep_duration = `ros::Duration(0.01)`,
		std::string *	error_msg = `NULL`
	)			const

Block until a transform is possible or it times out.

Parameters:

	target_frame	The frame into which to transform
	source_frame	The frame from which to transform
	time	The time at which to transform
	timeout	How long to block before failing
	polling_sleep_duration	How often to retest if failed
	error_msg	A pointer to a string which will be filled with why the transform failed, if not NULL

Definition at line 369 of file tf.cpp.

Member Data Documentation

ros::Duration tf::Transformer::cache_time [protected]

How long to cache transform history.

Definition at line 363 of file tf.h.

const double tf::Transformer::DEFAULT_CACHE_TIME = 10.0 [static]

The default amount of time to cache data in seconds.

Definition at line 90 of file tf.h.

const int64_t tf::Transformer::DEFAULT_MAX_EXTRAPOLATION_DISTANCE = 0ULL [static]

The default amount of time to extrapolate.

Definition at line 91 of file tf.h.

bool tf::Transformer::fall_back_to_wall_time_

Definition at line 385 of file tf.h.

std::map<unsigned int, std::string> tf::Transformer::frame_authority_ [protected]

Definition at line 359 of file tf.h.

boost::mutex tf::Transformer::frame_mutex_ [protected]

A mutex to protect testing and allocating new frames.

Definition at line 356 of file tf.h.

std::map<std::string, unsigned int> tf::Transformer::frameIDs_ [protected]

Definition at line 358 of file tf.h.

std::vector<std::string> tf::Transformer::frameIDs_reverse [protected]

Definition at line 360 of file tf.h.

std::vector< TimeCache*> tf::Transformer::frames_ [protected]

The internal storage class for ReferenceTransform.

An instance of this class is created for each frame in the system. This class natively handles the relationship between frames.

The derived class Pose3DCache provides a buffered history of positions with interpolation. The pointers to potential frames that the tree can be made of. The frames will be dynamically allocated at run time when set the first time.

Definition at line 334 of file tf.h.

bool tf::Transformer::interpolating [protected]

whether or not to interpolate or extrapolate

Definition at line 366 of file tf.h.

ros::Duration tf::Transformer::max_extrapolation_distance_ [protected]

whether or not to allow extrapolation

Definition at line 369 of file tf.h.

const unsigned int tf::Transformer::MAX_GRAPH_DEPTH = 100UL [static]

The maximum number of time to recurse before assuming the tree has a loop.

Definition at line 89 of file tf.h.

std::string tf::Transformer::tf_prefix_ [protected]

transform prefix to apply as necessary