Struct bevy::math::bounding::Aabb2d

pub struct Aabb2d {
    pub min: Vec2,
    pub max: Vec2,
}

A 2D axis-aligned bounding box, or bounding rectangle

Fields

min: Vec2

The minimum, conventionally bottom-left, point of the box

max: Vec2

The maximum, conventionally top-right, point of the box

Implementations

impl Aabb2d

pub fn new(center: Vec2, half_size: Vec2) -> Aabb2d

Constructs an AABB from its center and half-size.

Examples found in repository

examples/2d/bounding_2d.rs (line 348)

fn aabb_cast_system(
    mut gizmos: Gizmos,
    time: Res<Time>,
    mut volumes: Query<(&CurrentVolume, &mut Intersects)>,
) {
    let ray_cast = get_and_draw_ray(&mut gizmos, &time);
    let aabb_cast = AabbCast2d {
        aabb: Aabb2d::new(Vec2::ZERO, Vec2::splat(15.)),
        ray: ray_cast,
    };

    for (volume, mut intersects) in volumes.iter_mut() {
        let toi = match *volume {
            CurrentVolume::Aabb(a) => aabb_cast.aabb_collision_at(a),
            CurrentVolume::Circle(_) => None,
        };

        **intersects = toi.is_some();
        if let Some(toi) = toi {
            gizmos.rect_2d(
                aabb_cast.ray.ray.origin
                    + *aabb_cast.ray.ray.direction * toi
                    + aabb_cast.aabb.center(),
                0.,
                aabb_cast.aabb.half_size() * 2.,
                Color::GREEN,
            );
        }
    }
}

fn bounding_circle_cast_system(
    mut gizmos: Gizmos,
    time: Res<Time>,
    mut volumes: Query<(&CurrentVolume, &mut Intersects)>,
) {
    let ray_cast = get_and_draw_ray(&mut gizmos, &time);
    let circle_cast = BoundingCircleCast {
        circle: BoundingCircle::new(Vec2::ZERO, 15.),
        ray: ray_cast,
    };

    for (volume, mut intersects) in volumes.iter_mut() {
        let toi = match *volume {
            CurrentVolume::Aabb(_) => None,
            CurrentVolume::Circle(c) => circle_cast.circle_collision_at(c),
        };

        **intersects = toi.is_some();
        if let Some(toi) = toi {
            gizmos.circle_2d(
                circle_cast.ray.ray.origin
                    + *circle_cast.ray.ray.direction * toi
                    + circle_cast.circle.center(),
                circle_cast.circle.radius(),
                Color::GREEN,
            );
        }
    }
}

fn get_intersection_position(time: &Time) -> Vec2 {
    let x = (0.8 * time.elapsed_seconds()).cos() * 250.;
    let y = (0.4 * time.elapsed_seconds()).sin() * 100.;
    Vec2::new(x, y)
}

fn aabb_intersection_system(
    mut gizmos: Gizmos,
    time: Res<Time>,
    mut volumes: Query<(&CurrentVolume, &mut Intersects)>,
) {
    let center = get_intersection_position(&time);
    let aabb = Aabb2d::new(center, Vec2::splat(50.));
    gizmos.rect_2d(center, 0., aabb.half_size() * 2., Color::YELLOW);

    for (volume, mut intersects) in volumes.iter_mut() {
        let hit = match volume {
            CurrentVolume::Aabb(a) => aabb.intersects(a),
            CurrentVolume::Circle(c) => aabb.intersects(c),
        };

        **intersects = hit;
    }
}

examples/games/breakout.rs (lines 371-374)

fn check_for_collisions(
    mut commands: Commands,
    mut scoreboard: ResMut<Scoreboard>,
    mut ball_query: Query<(&mut Velocity, &Transform), With<Ball>>,
    collider_query: Query<(Entity, &Transform, Option<&Brick>), With<Collider>>,
    mut collision_events: EventWriter<CollisionEvent>,
) {
    let (mut ball_velocity, ball_transform) = ball_query.single_mut();

    // check collision with walls
    for (collider_entity, transform, maybe_brick) in &collider_query {
        let collision = collide_with_side(
            BoundingCircle::new(ball_transform.translation.truncate(), BALL_DIAMETER / 2.),
            Aabb2d::new(
                transform.translation.truncate(),
                transform.scale.truncate() / 2.,
            ),
        );

        if let Some(collision) = collision {
            // Sends a collision event so that other systems can react to the collision
            collision_events.send_default();

            // Bricks should be despawned and increment the scoreboard on collision
            if maybe_brick.is_some() {
                scoreboard.score += 1;
                commands.entity(collider_entity).despawn();
            }

            // reflect the ball when it collides
            let mut reflect_x = false;
            let mut reflect_y = false;

            // only reflect if the ball's velocity is going in the opposite direction of the
            // collision
            match collision {
                Collision::Left => reflect_x = ball_velocity.x > 0.0,
                Collision::Right => reflect_x = ball_velocity.x < 0.0,
                Collision::Top => reflect_y = ball_velocity.y < 0.0,
                Collision::Bottom => reflect_y = ball_velocity.y > 0.0,
            }

            // reflect velocity on the x-axis if we hit something on the x-axis
            if reflect_x {
                ball_velocity.x = -ball_velocity.x;
            }

            // reflect velocity on the y-axis if we hit something on the y-axis
            if reflect_y {
                ball_velocity.y = -ball_velocity.y;
            }
        }
    }
}

pub fn from_point_cloud( translation: Vec2, rotation: f32, points: &[Vec2] ) -> Aabb2d

Computes the smallest Aabb2d containing the given set of points, transformed by translation and rotation.

Panics

Panics if the given set of points is empty.

pub fn bounding_circle(&self) -> BoundingCircle

Computes the smallest BoundingCircle containing this Aabb2d.

pub fn closest_point(&self, point: Vec2) -> Vec2

Finds the point on the AABB that is closest to the given point.

If the point is outside the AABB, the returned point will be on the perimeter of the AABB. Otherwise, it will be inside the AABB and returned as is.

Examples found in repository

examples/games/breakout.rs (line 445)

fn collide_with_side(ball: BoundingCircle, wall: Aabb2d) -> Option<Collision> {
    if !ball.intersects(&wall) {
        return None;
    }

    let closest = wall.closest_point(ball.center());
    let offset = ball.center() - closest;
    let side = if offset.x.abs() > offset.y.abs() {
        if offset.x < 0. {
            Collision::Left
        } else {
            Collision::Right
        }
    } else if offset.y > 0. {
        Collision::Top
    } else {
        Collision::Bottom
    };

    Some(side)
}

Trait Implementations

impl BoundingVolume for Aabb2d

type Position = Vec2

The position type used for the volume. This should be Vec2 for 2D and Vec3 for 3D.

type HalfSize = Vec2

The type used for the size of the bounding volume. Usually a half size. For example an f32 radius for a circle, or a Vec3 with half sizes for x, y and z for a 3D axis-aligned bounding box

fn center(&self) -> <Aabb2d as BoundingVolume>::Position

Returns the center of the bounding volume.

fn half_size(&self) -> <Aabb2d as BoundingVolume>::HalfSize

Returns the half size of the bounding volume.

fn visible_area(&self) -> f32

Computes the visible surface area of the bounding volume. This method can be useful to make decisions about merging bounding volumes, using a Surface Area Heuristic.

fn contains(&self, other: &Aabb2d) -> bool

Checks if this bounding volume contains another one.

fn merge(&self, other: &Aabb2d) -> Aabb2d

Computes the smallest bounding volume that contains both self and other.

fn grow(&self, amount: <Aabb2d as BoundingVolume>::HalfSize) -> Aabb2d

Increase the size of the bounding volume in each direction by the given amount

fn shrink(&self, amount: <Aabb2d as BoundingVolume>::HalfSize) -> Aabb2d

Decrease the size of the bounding volume in each direction by the given amount

impl Clone for Aabb2d

fn clone(&self) -> Aabb2d

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for Aabb2d

fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>

Formats the value using the given formatter.

impl IntersectsVolume<Aabb2d> for Aabb2d

fn intersects(&self, other: &Aabb2d) -> bool

Check if a volume intersects with this intersection test

impl IntersectsVolume<Aabb2d> for AabbCast2d

fn intersects(&self, volume: &Aabb2d) -> bool

Check if a volume intersects with this intersection test

impl IntersectsVolume<Aabb2d> for BoundingCircle

fn intersects(&self, aabb: &Aabb2d) -> bool

Check if a volume intersects with this intersection test

impl IntersectsVolume<Aabb2d> for RayCast2d

fn intersects(&self, volume: &Aabb2d) -> bool

Check if a volume intersects with this intersection test

impl IntersectsVolume<BoundingCircle> for Aabb2d

fn intersects(&self, circle: &BoundingCircle) -> bool

Check if a volume intersects with this intersection test

impl Copy for Aabb2d