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 std::string &source_frame, const ros::Time &time, std::string *error_msg=NULL) const
	Test if a transform is possible.
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.
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_frame, const std::string &target_frame, 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 std::string &source_frame, const ros::Time &time, StampedTransform &transform) const
	Get the transform between two frames by frame ID.
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	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	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	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 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	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	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	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	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	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	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.
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.
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.
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.
virtual	~Transformer (void)
Public Attributes
bool	fall_back_to_wall_time_
Static Public Attributes
static const double	DEFAULT_CACHE_TIME = 10.0
	10.0 is the default amount of time to cache data in seconds, set in cpp file.
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::unordered_map < std::string, CompactFrameID >	M_StringToCompactFrameID
	The internal storage class for ReferenceTransform.
typedef boost::signal< void(void)>	TransformsChangedSignal
Protected Member Functions
TimeCache *	getFrame (unsigned int frame_number) const
	An accessor to get a frame, which will throw an exception if the frame is no there.
CompactFrameID	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.
CompactFrameID	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
Protected Attributes
ros::Duration	cache_time
	How long to cache transform history.
ros::Duration	cache_time_
	How long to cache transform history.
std::map< CompactFrameID, std::string >	frame_authority_
	A map to lookup the most recent authority for a given frame.
boost::recursive_mutex	frame_mutex_
	A mutex to protect testing and allocating new frames on the above vector.
M_StringToCompactFrameID	frameIDs_
std::vector< std::string >	frameIDs_reverse
	A map from CompactFrameID frame_id_numbers to string for debugging and output.
std::vector< TimeCache * >	frames_
	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.
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_
Private Member Functions
bool	canTransformInternal (CompactFrameID target_id, CompactFrameID source_id, const ros::Time &time, std::string *error_msg) const
bool	canTransformNoLock (CompactFrameID target_id, CompactFrameID source_id, const ros::Time &time, std::string *error_msg) const
void	createConnectivityErrorString (CompactFrameID source_frame, CompactFrameID target_frame, std::string *out) const
int	getLatestCommonTime (CompactFrameID target_frame, CompactFrameID source_frame, ros::Time &time, std::string *error_string) const
	Return the latest rostime which is common across the spanning set zero if fails to cross.
template<typename F >
int	walkToTopParent (F &f, ros::Time time, CompactFrameID target_id, CompactFrameID source_id, std::string *error_string) const

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 86 of file tf.h.

Member Typedef Documentation

typedef boost::unordered_map<std::string, CompactFrameID> tf::Transformer::M_StringToCompactFrameID [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.A map from string frame ids to CompactFrameID

Definition at line 334 of file tf.h.

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

Definition at line 382 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 200 of file tf.cpp.

Transformer::~Transformer ( void ) [virtual]

Definition at line 215 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 1527 of file tf.cpp.

std::string Transformer::allFramesAsDot ( ) const

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

Definition at line 1305 of file tf.cpp.

std::string Transformer::allFramesAsString ( ) const

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

regular transforms

Definition at line 1279 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

Definition at line 641 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 663 of file tf.cpp.

bool Transformer::canTransformInternal	(	CompactFrameID	target_id,
		CompactFrameID	source_id,
		const ros::Time &	time,
		std::string *	error_msg
	)		const `[private]`

Definition at line 634 of file tf.cpp.

bool Transformer::canTransformNoLock	(	CompactFrameID	target_id,
		CompactFrameID	source_id,
		const ros::Time &	time,
		std::string *	error_msg
	)		const `[private]`

Definition at line 617 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.

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

regular transforms

Definition at line 1251 of file tf.cpp.

void Transformer::clear ( )

Clear all data.

Definition at line 227 of file tf.cpp.

void Transformer::createConnectivityErrorString	(	CompactFrameID	source_frame,
		CompactFrameID	target_frame,
		std::string *	out
	)		const `[private]`

Definition at line 721 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 708 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 1398 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 1382 of file tf.cpp.

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

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

Definition at line 746 of file tf.cpp.

int Transformer::getLatestCommonTime	(	CompactFrameID	target_frame,
		CompactFrameID	source_frame,
		ros::Time &	time,
		std::string *	error_string
	)		const `[private]`

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

Definition at line 762 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 679 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.

CompactFrameID 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 420 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 454 of file tf.h.

CompactFrameID 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 437 of file tf.h.

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 443 of file tf.cpp.

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 489 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 512 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 503 of file tf.cpp.

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

Hack method to work around #4150

Definition at line 396 of file tf.h.

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

Reimplemented in tf::TransformListener.

Definition at line 1380 of file tf.cpp.

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

Definition at line 1533 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 716 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 372 of file tf.cpp.

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

Definition at line 332 of file tf.h.

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 1438 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 1497 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 1448 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 1512 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 1407 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 1459 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 1420 of file tf.cpp.

void tf::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.

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 589 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 670 of file tf.cpp.

template<typename F >

int Transformer::walkToTopParent	(	F &	f,
		ros::Time	time,
		CompactFrameID	target_id,
		CompactFrameID	source_id,
		std::string *	error_string
	)		const `[private]`