SimpleMap Class Reference

Simple 2D uint8_t grid using basic C++ types, with full metric conversion support. More...

#include <SimpleMap.hpp>

Public Member Functions
uint8_t &	at (int x, int y)
	Access a cell (non-const) at (x, y).
uint8_t	at (int x, int y) const
	Access a cell (const) at (x, y).
std::pair< double, double >	cell_to_metric (int x, int y) const
	Converts a cell index (x, y) to real-world metric coordinates (meters).
bool	check_bounds_metric (double mx, double my) const
	Checks if given metric coordinates are within the map bounds.
void	deep_copy (const SimpleMap &other)
	Performs a deep copy from another SimpleMap.
std::shared_ptr< SimpleMap >	downsample (double new_resolution) const
	Creates a downsampled version of the map to match a target resolution.
std::shared_ptr< SimpleMap >	downsample_factor (int factor) const
	Creates a downsampled version of the map by an integer factor.
void	fill (uint8_t value)
	Set all cells to a given value.
void	from_occupancy_grid (const nav_msgs::msg::OccupancyGrid &grid_msg)
	Load map data and metadata from a nav_msgs::msg::OccupancyGrid message.
size_t	height () const
	Returns the height (number of rows) of the map.
void	initialize (int width, int height, double resolution, double origin_x, double origin_y, bool initial_value=false)
	Initialize the map to new dimensions, resolution, and origin.
bool	load_from_file (const std::string &path)
	Loads the map from a file, reading metadata and cell data.
std::pair< int, int >	metric_to_cell (double mx, double my) const
	Converts real-world metric coordinates (meters) to a cell index (x, y).
double	origin_x () const
	Returns the metric origin x coordinate.
double	origin_y () const
	Returns the metric origin y coordinate.
void	print (bool view_data=false) const
	Prints metadata and optionally all map cell values with coordinates.
double	resolution () const
	Returns the resolution (cell size in meters).
bool	save_to_file (const std::string &path) const
	Saves the map to a file, including metadata and cell data.
	SimpleMap ()
	Default constructor.
void	to_occupancy_grid (nav_msgs::msg::OccupancyGrid &grid_msg) const
	Updates a nav_msgs::msg::OccupancyGrid message from the SimpleMap contents.
size_t	width () const
	Returns the width (number of columns) of the map.

Detailed Description

Simple 2D uint8_t grid using basic C++ types, with full metric conversion support.

Supports arbitrary metric origins, allowing negative coordinates.

Constructor & Destructor Documentation

SimpleMap()

SimpleMap

(

)

Default constructor.

Creates an empty (0x0) SimpleMap with 1.0 meter resolution and origin (0.0, 0.0).

Member Function Documentation

at() [1/2]

uint8_t & at	(	int	x,
		int	y )

Access a cell (non-const) at (x, y).

Exceptions

std::out_of_range

if (x,y) is out of bounds.

at() [2/2]

uint8_t at	(	int	x,
		int	y ) const

Access a cell (const) at (x, y).

Exceptions

std::out_of_range

if (x,y) is out of bounds.

cell_to_metric()

std::pair< double, double > cell_to_metric	(	int	x,
		int	y ) const

Converts a cell index (x, y) to real-world metric coordinates (meters).

Parameters

x	Cell column index.
y	Cell row index.

Returns

Pair (meters_x, meters_y).

check_bounds_metric()

bool check_bounds_metric	(	double	mx,
		double	my ) const

Checks if given metric coordinates are within the map bounds.

Parameters

mx	Metric x coordinate.
my	Metric y coordinate.

Returns

true if inside the map bounds, false otherwise.

deep_copy()

void deep_copy

(

const SimpleMap &

other

)

Performs a deep copy from another SimpleMap.

Copies width, height, resolution, origin, and all grid data.

Parameters

other

The SimpleMap to copy from.

downsample()

std::shared_ptr< SimpleMap > downsample

(

double

new_resolution

)

const

Creates a downsampled version of the map to match a target resolution.

Parameters

new_resolution

New desired resolution (must be a multiple of current).

Returns

A shared pointer to the new downsampled SimpleMap.

downsample_factor()

std::shared_ptr< SimpleMap > downsample_factor

(

int

factor

)

const

Creates a downsampled version of the map by an integer factor.

Parameters

factor

Integer factor (>1) to reduce resolution.

Returns

A shared pointer to the new downsampled SimpleMap.

fill()

void fill

(

uint8_t

value

)

Set all cells to a given value.

Parameters

value

Value to fill the map with.

from_occupancy_grid()

void from_occupancy_grid

(

const nav_msgs::msg::OccupancyGrid &

grid_msg

)

Load map data and metadata from a nav_msgs::msg::OccupancyGrid message.

This function resizes the internal grid to match the occupancy grid dimensions, sets the resolution and origin, and copies the data.

Parameters

grid_msg

The occupancy grid message to load from.

height()

size_t height

(

)

const

Returns the height (number of rows) of the map.

initialize()

void initialize	(	int	width,
		int	height,
		double	resolution,
		double	origin_x,
		double	origin_y,
		bool	initial_value = false )

Initialize the map to new dimensions, resolution, and origin.

Parameters

width	Number of columns.
height	Number of rows.
resolution	Size of each cell in meters.
origin_x	Metric X coordinate corresponding to cell (0,0).
origin_y	Metric Y coordinate corresponding to cell (0,0).
initial_value	Value to initialize all cells.

load_from_file()

bool load_from_file

(

const std::string &

path

)

Loads the map from a file, reading metadata and cell data.

Parameters

path	Path to the input file.

Returns

true if the file was read successfully and is valid, false otherwise.

metric_to_cell()

std::pair< int, int > metric_to_cell	(	double	mx,
		double	my ) const

Converts real-world metric coordinates (meters) to a cell index (x, y).

Parameters

mx	Metric x coordinate.
my	Metric y coordinate.

Returns

Pair (x, y) cell indices.

Exceptions

std::out_of_range

if resulting indices are out of map bounds.

origin_x()

double origin_x

(

)

const

Returns the metric origin x coordinate.

origin_y()

double origin_y

(

)

const

Returns the metric origin y coordinate.

print()

void print

(

bool

view_data = false

)

const

Prints metadata and optionally all map cell values with coordinates.

Parameters

view_data

If true, prints cell-by-cell content with coordinates. Default is false.

resolution()

double resolution

(

)

const

Returns the resolution (cell size in meters).

save_to_file()

bool save_to_file

(

const std::string &

path

)

const

Saves the map to a file, including metadata and cell data.

Parameters

path	Path to the output file.

Returns

true if the file was written successfully, false otherwise.

to_occupancy_grid()

void to_occupancy_grid

(

nav_msgs::msg::OccupancyGrid &

grid_msg

)

const

Updates a nav_msgs::msg::OccupancyGrid message from the SimpleMap contents.

Cells are mapped as follows:

• true -> 100 (occupied)
• false -> 0 (free)

If the grid dimensions do not match, the message is rdata_esized automatically.

Parameters

grid_msg

The occupancy grid message to fill or update.

width()

size_t width

(

)

const

Returns the width (number of columns) of the map.

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

• easynav_simple_common/include/easynav_simple_common/SimpleMap.hpp
• easynav_simple_common/src/easynav_simple_common/SimpleMap.cpp