Struct flat_spatial::shapegrid::AABBGrid

pub struct AABBGrid<O: Copy, AB: AABB> { /* private fields */ }

ShapeGrid is a generic aabb-based spatial partitioning structure that uses a generic storage of cells which acts as a grid instead of a tree.

Fast queries

In theory, ShapeGrid should be faster than a quadtree/r-tree because it has no log costs (calculating the cells around a point is trivial).
However, it only works if the cell size is adapted to the problem, much like how a tree has to be balanced to be efficient.

Dynamicity

ShapeGrid's allows eager removals and position updates, however for big aabbs (spanning many cells) this can be expensive, so beware.

Use this grid for mostly static objects with the occasional removal/position update if needed.

A SlotMap is used for objects managing, adding a level of indirection between aabbs and objects. SlotMap is used because removal doesn’t alter handles given to the user, while still having constant time access. However it requires O to be copy, but SlotMap's author stated that they were working on a similar map where Copy isn’t required.

About object management

In theory, you don’t have to use the object management directly, you can make your custom Handle -> Object map by specifying “()” to be the object type. (This can be useful if your object is not Copy) Since () is zero sized, it should probably optimize away a lot of the object management code.

use flat_spatial::AABBGrid;
use euclid::default::Rect;

let mut g: AABBGrid<(), Rect<f32>> = AABBGrid::new(10);
let handle = g.insert(Rect::new([0.0, 0.0].into(), [10.0, 10.0].into()), ());
// Use handle however you want

Implementations

impl<O: Copy, AB: AABB> AABBGrid<O, AB>

pub fn new(cell_size: i32) -> Self

Creates an empty grid. The cell size should be about the same magnitude as your queries size.

pub fn clear(&mut self) -> impl Iterator<Item = (AB, O)>

Clears the grid.

pub fn insert(&mut self, aabb: AB, obj: O) -> ShapeGridHandle

Inserts a new object with a position and an associated object Returns the unique and stable handle to be used with get_obj

pub fn set_aabb(&mut self, handle: ShapeGridHandle, aabb: AB)

Updates the aabb of an object.

pub fn remove(&mut self, handle: ShapeGridHandle) -> Option<O>

Removes an object from the grid.

pub fn handles(&self) -> impl Iterator<Item = ShapeGridHandle> + '_

Iterate over all handles

pub fn objects(&self) -> impl Iterator<Item = &O> + '_

Iterate over all objects

pub fn get(&self, id: ShapeGridHandle) -> Option<&StoreObject<O, AB>>

Returns a reference to the associated object and its position, using the handle.

pub fn get_mut(&mut self, id: ShapeGridHandle) -> Option<&mut StoreObject<O, AB>>

Returns a mutable reference to the associated object and its position, using the handle.

pub fn storage(&self) -> &SparseStorage<ShapeGridCell>

The underlying storage

pub fn query(
    &self,
    aabb: AB
) -> impl Iterator<Item = (ShapeGridHandle, &AB, &O)> + '_

Queries for objects intersecting a given AABB.

pub fn query_broad(&self, bbox: AB) -> impl Iterator<Item = ShapeGridHandle> + '_

Queries for all objects in the cells intersecting the given AABB

pub fn query_visitor(
    &self,
    aabb: AB,
    visitor: impl FnMut(ShapeGridHandle, &AB, &O)
)

Queries for objects intersecting a given AABB. Uses a visitor for slightly better performance.

pub fn query_broad_visitor(&self, bbox: AB, visitor: impl FnMut(ShapeGridHandle))

Queries for all objects in the cells intersecting the given AABB Uses a visitor for slightly better performance.

pub fn len(&self) -> usize

Returns the number of objects currently available

pub fn is_empty(&self) -> bool

Checks if the grid contains objects or not

Trait Implementations

impl<O: Clone + Copy, AB: Clone + AABB> Clone for AABBGrid<O, AB>

fn clone(&self) -> AABBGrid<O, AB>

Returns a copy of the value.

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

Performs copy-assignment from source.