navfn::NavFn Class Reference

Navigation function class. Holds buffers for costmap, navfn map. Maps are pixel-based. Origin is upper left, x is right, y is down. More...

#include <navfn.h>

Public Member Functions
bool	calcNavFnAstar ()
	Calculates a plan using the A* heuristic, returns true if one is found. More...
bool	calcNavFnDijkstra (bool atStart=false)
	Caclulates the full navigation function using Dijkstra. More...
int	calcPath (int n, int *st=NULL)
	Calculates the path for at mose <n> cycles. More...
void	display (void fn(NavFn *nav), int n=100)
float	getLastPathCost ()
	Gets the cost of the path found the last time a navigation function was computed. More...
int	getPathLen ()
	Accessor for the length of a path. More...
float *	getPathX ()
	Accessor for the x-coordinates of a path. More...
float *	getPathY ()
	Accessor for the y-coordinates of a path. More...
float	gradCell (int n)
void	initCost (int k, float v)
	Initialize cell k with cost v for propagation. More...
	NavFn (int nx, int ny)
	Constructs the planner. More...
bool	propNavFnAstar (int cycles)
	Run propagation for <cycles> iterations, or until start is reached using the best-first A* method with Euclidean distance heuristic. More...
bool	propNavFnDijkstra (int cycles, bool atStart=false)
	Run propagation for <cycles> iterations, or until start is reached using breadth-first Dijkstra method. More...
void	savemap (const char *fname)
void	setCostmap (const COSTTYPE *cmap, bool isROS=true, bool allow_unknown=true)
	Set up the cost array for the planner, usually from ROS. More...
void	setGoal (int *goal)
	Sets the goal position for the planner. Note: the navigation cost field computed gives the cost to get to a given point from the goal, not from the start. More...
void	setNavArr (int nx, int ny)
	Sets or resets the size of the map. More...
void	setStart (int *start)
	Sets the start position for the planner. Note: the navigation cost field computed gives the cost to get to a given point from the goal, not from the start. More...
void	setupNavFn (bool keepit=false)
void	updateCell (int n)
	Updates the cell at index n. More...
void	updateCellAstar (int n)
	Updates the cell at index n using the A* heuristic. More...
	~NavFn ()

Public Attributes
COSTTYPE *	costarr
int *	curP
int	curPe
float	curT
void(*	displayFn )(NavFn *nav)
int	displayInt
int	goal [2]
float *	gradx
float *	grady
float	last_path_cost_
int *	nextP
int	nextPe
int	nobs
int	npath
int	npathbuf
int	ns
int	nx
int	ny
int *	overP
int	overPe
float	pathStep
float *	pathx
float *	pathy
int *	pb1
int *	pb2
int *	pb3
bool *	pending
float *	potarr
float	priInc
int	start [2]

Detailed Description

Navigation function class. Holds buffers for costmap, navfn map. Maps are pixel-based. Origin is upper left, x is right, y is down.

Definition at line 106 of file navfn.h.

Constructor & Destructor Documentation

navfn::NavFn::NavFn	(	int	nx,
		int	ny
	)

Constructs the planner.

Parameters

nx	The x size of the map
ny	The y size of the map

Definition at line 110 of file navfn.cpp.

navfn::NavFn::~NavFn

(

)

Definition at line 143 of file navfn.cpp.

Member Function Documentation

bool navfn::NavFn::calcNavFnAstar

(

)

Calculates a plan using the A* heuristic, returns true if one is found.

Returns

True if a plan is found, false otherwisecalculates a plan, returns true if found

Definition at line 319 of file navfn.cpp.

bool navfn::NavFn::calcNavFnDijkstra

(

bool

atStart = false

)

Caclulates the full navigation function using Dijkstra.

calculates the full navigation function

Definition at line 290 of file navfn.cpp.

int navfn::NavFn::calcPath	(	int	n,
		int *	st = NULL
	)

Calculates the path for at mose <n> cycles.

Parameters

n	The maximum number of cycles to run for

Returns

The lenght of the path foundcalculates path for at most <n> cycles, returns path length, 0 if none

Definition at line 785 of file navfn.cpp.

void navfn::NavFn::display	(	void	fnNavFn *nav,
		int	n = 100
	)

display callback <n> is the number of cycles between updates

Definition at line 1014 of file navfn.cpp.

float navfn::NavFn::getLastPathCost

(

)

Gets the cost of the path found the last time a navigation function was computed.

Returns

The cost of the last path foundReturn cost of path found the last time A* was called

Definition at line 767 of file navfn.cpp.

int navfn::NavFn::getPathLen

(

)

Accessor for the length of a path.

Returns

The length of a pathlength of path, 0 if not found

Definition at line 348 of file navfn.cpp.

float * navfn::NavFn::getPathX

(

)

Accessor for the x-coordinates of a path.

Returns

The x-coordinates of a pathx-coordinates of path

Definition at line 346 of file navfn.cpp.

float * navfn::NavFn::getPathY

(

)

Accessor for the y-coordinates of a path.

Returns

The y-coordinates of a pathy-coordinates of path

Definition at line 347 of file navfn.cpp.

float navfn::NavFn::gradCell

(

int

n

)

calculates gradient at cell <n>, returns norm

Definition at line 955 of file navfn.cpp.

void navfn::NavFn::initCost	(	int	k,
		float	v
	)

Initialize cell k with cost v for propagation.

Parameters

k	the cell to initialize
v	the cost to give to the cellinitialize cell <k> with cost <v>, for propagation

Definition at line 419 of file navfn.cpp.

bool navfn::NavFn::propNavFnAstar

(

int

cycles

)

Run propagation for <cycles> iterations, or until start is reached using the best-first A* method with Euclidean distance heuristic.

Parameters

cycles

The maximum number of iterations to run for

Returns

true if the start point is reachedreturns true if start point found

Definition at line 692 of file navfn.cpp.

bool navfn::NavFn::propNavFnDijkstra	(	int	cycles,
		bool	atStart = false
	)

Run propagation for <cycles> iterations, or until start is reached using breadth-first Dijkstra method.

Parameters

cycles	The maximum number of iterations to run for
atStart	Whether or not to stop when the start point is reached

Returns

true if the start point is reachedreturns true if start point found or full prop

Definition at line 615 of file navfn.cpp.

void navfn::NavFn::savemap

(

const char *

fname

)

save costmap write out costmap and start/goal states as fname.pgm and fname.txt

Definition at line 1027 of file navfn.cpp.

void navfn::NavFn::setCostmap	(	const COSTTYPE *	cmap,
		bool	isROS = true,
		bool	allow_unknown = true
	)

Set up the cost array for the planner, usually from ROS.

Parameters

cmap	The costmap
isROS	Whether or not the costmap is coming in in ROS format
allow_unknown	Whether or not the planner should be allowed to plan through unknown spacesets up the cost map

Definition at line 228 of file navfn.cpp.

void navfn::NavFn::setGoal

(

int *

goal

)

Sets the goal position for the planner. Note: the navigation cost field computed gives the cost to get to a given point from the goal, not from the start.

goal and start positions

Parameters

goal	the goal position

Definition at line 173 of file navfn.cpp.

void navfn::NavFn::setNavArr	(	int	nx,
		int	ny
	)

Sets or resets the size of the map.

Parameters

nx	The x size of the map
ny	The y size of the map sets or resets the size of the map

Definition at line 193 of file navfn.cpp.

void navfn::NavFn::setStart

(

int *

start

)

Sets the start position for the planner. Note: the navigation cost field computed gives the cost to get to a given point from the goal, not from the start.

Parameters

start

the start position

Definition at line 181 of file navfn.cpp.

void navfn::NavFn::setupNavFn

(

bool

keepit = false

)

resets all nav fn arrays for propagation

Definition at line 365 of file navfn.cpp.

void navfn::NavFn::updateCell ( int  n )

inline

Updates the cell at index n.

propagation

Parameters

n	The index to updateupdates the cell at index <n>

Definition at line 440 of file navfn.cpp.

void navfn::NavFn::updateCellAstar ( int  n )

inline

Updates the cell at index n using the A* heuristic.

Parameters

n	The index to updateupdates the cell at index <n>, uses A* heuristic

Definition at line 525 of file navfn.cpp.

Member Data Documentation

COSTTYPE* navfn::NavFn::costarr

cell arrays cost array in 2D configuration space

Definition at line 170 of file navfn.h.

int* navfn::NavFn::curP

Definition at line 177 of file navfn.h.

int navfn::NavFn::curPe

Definition at line 178 of file navfn.h.

float navfn::NavFn::curT

block priority thresholds current threshold

Definition at line 181 of file navfn.h.

void(* navfn::NavFn::displayFn) (NavFn *nav)

display function itself

Definition at line 258 of file navfn.h.

int navfn::NavFn::displayInt

save second argument of display() above

Definition at line 257 of file navfn.h.

int navfn::NavFn::goal[2]

Definition at line 197 of file navfn.h.

float* navfn::NavFn::gradx

gradient and paths

Definition at line 237 of file navfn.h.

float * navfn::NavFn::grady

gradient arrays, size of potential array

Definition at line 237 of file navfn.h.

float navfn::NavFn::last_path_cost_

Holds the cost of the path found the last time A* was called

Definition at line 242 of file navfn.h.

int * navfn::NavFn::nextP

Definition at line 177 of file navfn.h.

int navfn::NavFn::nextPe

Definition at line 178 of file navfn.h.

int navfn::NavFn::nobs

number of obstacle cells

Definition at line 173 of file navfn.h.

int navfn::NavFn::npath

number of path points

Definition at line 239 of file navfn.h.

int navfn::NavFn::npathbuf

size of pathx, pathy buffers

Definition at line 240 of file navfn.h.

int navfn::NavFn::ns

size of grid, in pixels

Definition at line 124 of file navfn.h.

int navfn::NavFn::nx

Definition at line 124 of file navfn.h.

int navfn::NavFn::ny

Definition at line 124 of file navfn.h.

int * navfn::NavFn::overP

priority buffer block ptrs

Definition at line 177 of file navfn.h.

int navfn::NavFn::overPe

end points of arrays

Definition at line 178 of file navfn.h.

float navfn::NavFn::pathStep

step size for following gradient

Definition at line 253 of file navfn.h.

float* navfn::NavFn::pathx

Definition at line 238 of file navfn.h.

float * navfn::NavFn::pathy

path points, as subpixel cell coordinates

Definition at line 238 of file navfn.h.

int* navfn::NavFn::pb1

block priority buffers

Definition at line 176 of file navfn.h.

int * navfn::NavFn::pb2

Definition at line 176 of file navfn.h.

int * navfn::NavFn::pb3

storage buffers for priority blocks

Definition at line 176 of file navfn.h.

bool* navfn::NavFn::pending

pending cells during propagation

Definition at line 172 of file navfn.h.

float* navfn::NavFn::potarr

potential array, navigation function potential

Definition at line 171 of file navfn.h.

float navfn::NavFn::priInc

priority threshold increment

Definition at line 182 of file navfn.h.

int navfn::NavFn::start[2]

Definition at line 198 of file navfn.h.

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

• navfn.h
• navfn.cpp