World

class Kilosim::World

The World provides the base environment for running simulations. It represents a two-dimensional bounded arena for simulating Kilobots.

The user can configure the World dimensions and the monochrome light intensity at every point in the World (with a LightPattern), and add Robots to the World to simulate.

After initial configuration, the simulation is run simply by invoking the step() method, which processes a single time step (1/32 second, by default) for all Robots.

References to a World are used by both the Logger (to save information about the Robots during simulation) and the Viewer (to visualize the simulation).

It manages fixed-step simulated control over all Robots placed in it.

Public Functions

World(const double arena_width, const double arena_height, const std::string light_pattern_src = "", const uint32_t num_threads = 0)

Construct a world of a fixed size with the background light pattern

Parameters

  • arena_width – Width of the rectangular World/arena in mm

  • arena_height – Height of the rectangular World/arena in mm

  • light_pattern_src – Name of image file of the light pattern to use. Aspect ratio should match the arena, but no specific resolution is mandated. If no light_pattern_src is provided (empty string), the background will be black.

  • num_threads – How many threads to parallelize the simulation over. If set to 0 (default), dynamic threading will be used.

void step()

Run a step of the simulator. This runs the controllers, communication, pseudo-physics, and movement for all Robots. It also increments the tick time.

This is what you should call in your main function to run the simulation.

bool has_light_pattern() const

Check whether the World has a light pattern image set

Returns

Whether LightPattern has an image source

void set_light_pattern(const std::string light_img_src)

Set the world’s light pattern using the given image file. The image type must be supported by SFML’s Image::loadFromFile

Parameters

light_img_src – Name and location of the image file to use for light pattern

void add_robot(Robot *robot)

Add a robot to the world by its pointer.

Warning

It is possible right now to add a Robot twice, so be careful.

void remove_robot(Robot *robot)

Remove a robot from the world by its pointer

TODO: remove_robot is currently unimplemented…

Warning

…I haven’t implemented this yet.

uint16_t get_tick_rate() const

Get the tick rate (should be 32 by default, if not changed by user).

Returns

Number of simulation ticks per second of real-world (wall clock) time

void set_tick_rate(const uint16_t tick_rate)

Set the tick rate of the simulation (how many ticks per second are simulated).

Parameters

tick_rate – Number of simulation ticks per second of real-world (wall clock) time

uint32_t get_tick() const

Get the current tick of the simulation (only set by simulator)

Returns

Number of ticks since simulation started

double get_time() const

Get the current computed time in seconds (from tick and tickRate)

Returns

Time since simulation started (in seconds)

std::vector<Robot*> &get_robots()

Get a reference to a vector of pointers to all robots in the world. This is useful for Logger and Viewer functions, but you likely won’t need to use it as an end-user.

Returns

All the Robots added to the world

std::vector<double> get_dimensions() const

Get the dimensions of the world (in mm)

Returns

2-element [width, height] vector of dimensions in mm

void check_validity() const

Check that the world is in a valid state. (i.e., all Robots in the World are within the arena bounds, and none are overlapping).

Note

If you want to allow intersections, you can just not call this.

Throws

std::runtime_error – if any robots are out of bounds or overlapping