The system part of a full ECS (Entity-Component-System).
It also contains a World
structure, which holds the game data used by systems,
as well as the Dispatcher
that is used to execute systems in parallel and in
an optimised order.
Add the following to you Cargo.toml file:
world_dispatcher = "1.0.0"
Use it like so: ```rust use world_dispatcher::*; fn main() { #[derive(Default)] pub struct A;
let mut world = World::default();
let sys = (|_comps: &A| Ok(())).system();
let mut dispatch = DispatcherBuilder::new().add_system(sys).build(&mut world);
dispatch.run_seq(&world).unwrap();
dispatch.run_seq(&world).unwrap();
dispatch.run_seq(&world).unwrap();
assert!(world.get::<A>().is_ok());
} ```
It is also possible to convert most functions into systems.
There are five requirements for this:
- Take only & and &mut references as arguments
- Return a SystemResult
- Use all & references before all &mut references in the arguments.
- Do not use the same type twice in the arguments.
- All types in the arguments must implement Default
. If they don't, use
&/&mut Option<YourType>
instead.
```rust
use world_dispatcher::*;
pub struct A;
pub struct B;
pub struct C; pub struct D;
fn systemfunction(a: &A, b: &B, _c: &mut C, d: &mut Option
fn main() {
let mut world = World::default();
// Will automatically create A, B, C, Option
dispatch.run_seq(&world).unwrap();
dispatch.run_seq(&world).unwrap();
dispatch.run_seq(&world).unwrap();
assert!(world.get::<Option<D>>().unwrap().is_some());
} ```
CC0, public domain.
TLDR: You can do whatever you want with it. Have fun!