[](https://ci.codeberg.org/repos/15785)
[](https://docs.rs/rstared/)
[](https://crates.io/crates/rstared)
[](#licence)
# rstared
`rstared::RTree` is a simple
[decorator](https://en.wikipedia.org/wiki/Decorator_pattern)
that adds a passively listening R-tree,
[`rstar::RTree`](https://docs.rs/rstar/0.12.2/rstar/struct.RTree.html), to the
following collections:
- [`HashMap`](https://doc.rust-lang.org/std/collections/struct.HashMap.html), gated by the `std` feature (enabled by default);
- [`HashSet`](https://doc.rust-lang.org/stable/std/collections/struct.HashSet.html), gated by the `std` feature (enabled by default);
- [`BTreeMap`](https://doc.rust-lang.org/std/collections/struct.BTreeMap.html), not feature-gated;
- [`BTreeSet`](https://doc.rust-lang.org/stable/std/collections/struct.BTreeSet.html), not feature-gated;
- [`stable_vec::StableVec`](https://docs.rs/stable-vec/latest/stable_vec/),
gated by the `stable-vec` feature (example usage:
[examples/stable_vec.rs](./examples/stable_vec.rs));
- [`thunderdome::Arena`](https://docs.rs/thunderdome/latest/thunderdome/),
gated by the `thunderdome` feature (example usage:
[examples/thunderdome.rs](./examples/thunderdome.rs)).
## Usage
### Basic usage
Add `rstared` as a dependency to your `Cargo.toml` together with the features
that gate the collections you are going to use. For example, to use `rstared`
with `stable_vec::StableVec` and `thunderdome::Arena`, write
```toml
[dependencies]
rstared = { version = "0.1", features = ["stable-vec", "thunderdome"] }
```
Following is a basic usage example taken from
[examples/basic_usage.rs](./examples/basic_usage.rs):
```rust
use std::collections::HashMap;
use rstar::{AABB, primitives::Rectangle};
use rstared::{Insert, RTreed, Remove};
fn main() {
// A hashmap of 2D rectangles will be the underlying collection.
let rect_hashmap: HashMap<i32, Rectangle<(i32, i32)>> = HashMap::new();
// Wrap `RTreed` around the hashmap.
let mut rtreed =
RTreed::<i32, Rectangle<(i32, i32)>, HashMap<i32, Rectangle<(i32, i32)>>>::new(
rect_hashmap,
);
// Insert two rectangles, recording them in the R-tree.
rtreed.insert(1, Rectangle::from_corners((0, 0), (1, 1)));
rtreed.insert(2, Rectangle::from_corners((1, 1), (2, 2)));
// Locate the two rectangles in the R-tree.
assert_eq!(
rtreed
.rtree()
.locate_in_envelope(&AABB::from_corners((0, 0), (2, 2)))
.count(),
2
);
// Now remove one of the rectangles, recording this in the R-tree.
rtreed.remove(&1);
// Make the same query to the R-tree as before.
// Only one rectangle is now present.
assert_eq!(
rtreed
.rtree()
.locate_in_envelope(&AABB::from_corners((0, 0), (2, 2)))
.count(),
1
);
}
```
### Usage on maps with pushing
Some data structures with map semantics also provide a special type of insertion
where a value is inserted without specifying a key, which the structure
instead automatically generates and returns by itself. This operation is called
"pushing".
If a supported type has a push interface, you can use it through `RTreed` by
calling `.push()`, like this:
```rust-ignore
rtreed.push('A');
```
`StableVec` and `thunderdome::Arena` are instances of supported pushable maps.
## Contributing
We welcome issues and pull requests from anyone both to our canonical
[repository](https://codeberg.org/topola/rstared) on Codeberg and to our GitHub
[mirror](https://github.com/mikwielgus/rstared).
**NOTE:** This repository currently contains a Git submodule:
`src/maplike`, which we currently use to share functionality with the
[`undoredo`](https://docs.rs/undoredo/) crate to avoid creating another crate
for now. After `git clone`, remember to run
```bash
git submodule update --init
```
in the cloned directory.
## Licence
`undoredo` is dual-licensed as under either of
- [MIT license](./LICENSES/MIT.txt),
- [Apache License, Version 2.0](./LICENSES/Apache-2.0.txt),
at your option.