Computing collisions

CollisionComputation

class CollisionComputation

This class compute collisions of moving points with lists of DiscCache and LineSegment.

__init__() → None

Construct an instance.

dynamic_free_distance(angle: float, max_distance: float, speed: float) → float

Returns the free distance if the agent will be move

Parameters:

• angle – The angle (absolute)

• max_distance – The maximal distance to consider

• speed – The speed of the agent

Returns:

The distance in direction angle before possibly colliding

get_angles_for_sector(from_angle: float, length: float, resolution: int) → list[float]

Return regularly sampled angles.

Parameters:

• from – The interval lower bound

• length – The length of the interval

• resolution – The number of values in the interval

Returns:

Angles regularly sampled in the interval [from, from + length].

get_contour_for_sector(from_angle: float, length: float, resolution: int, max_distance: float, dynamic: bool, speed: float = 0) → list[float]

Return the polar contour for an interval of headings.

Parameters:

• from – The interval lower bound

• length – The length of the interval

• resolution – The number of values in the interval

• max_distance – The maximum distance to consider (collision behind this distance are effectively ignored)

• dynamic – If the agent is moving

• speed – The speed at which the agent is moving

Returns:

An arrays of angles sampled regularly in the interval [from, from + length] and one array with the free distance in their direction.

get_free_distance_for_sector(from_angle: float, length: float, resolution: int, max_distance: float, dynamic: bool, speed: float = 0) → list[float]

Return the free distance to collision for an interval of headings.

Parameters:

• from – The interval lower bound

• length – The length of the interval

• resolution – The number of values in the interval

• max_distance – The maximum distance to consider (collision behind this distance are effectively ignored)

• dynamic – If the agent is moving

• speed – The speed at which the agent is moving

Returns:

The free distance for each angle in the interval [from, from + length].

setup(pose: navground.core.Pose2 = navground.core.Pose2((0, 0), 0), margin: float = 0, line_segments: list[navground.core.LineSegment] = [], static_discs: list[navground.core.Disc] = [], dynamic_discs: list[navground.core.Neighbor] = []) → None

Set the state from collections of LineSegment, Disc, and Neighbor.

Parameters:

• pose – The pose

• margin – The margin

• line_segments – The line segments

• static_discs – The static discs

• dynamic_discs – The dynamic discs

static_free_distance(angle: float, max_distance: float, include_neighbors: bool = True) → float

Returns the free distance if the agent will be static

Parameters:

• angle – The angle (absolute)

• max_distance – The maximal distance to consider

• include_neighbors – Indicates if the neighbors should be included in the computation

Returns:

The distance in direction angle before possibly colliding

CachedCollisionComputation

class CachedCollisionComputation

Bases: CollisionComputation

This class extend CollisionComputation to cache the results.

It assumes that the agents is only interested in possible collisions when moving in directions comprised in an interval \([\alpha, \alpha + \Delta]\), represented by in \(N\) points at regular steps, only up to a maximal distance \(D\), and that the agent moves at at given speed.

__init__() → None

Construct an instance

get_free_distance(dynamic: bool) → list[float]

Returns the free distance to collision for the cached interval of headings.

Parameters:

dynamic – If the agent is moving

Returns:

The distance before possibly colliding for each direction in the interval \([\alpha, \alpha + \Delta]\).

property length

Type:

float

The cache interval length \(\delta\).

property max_distance

Type:

float

The maximal distance \(d\) to consider

property min_angle

Type:

float

The cache interval lower bound \(\alpha\).

property resolution

Type:

int

The resolution: the number of discrete angles \(n\).

property speed

Type:

float

The agent speed.