bevy/crates/bevy_ecs/src/system/exclusive_system_param.rs
dis-da-moe 8853bef6df implement TypeUuid for primitives and fix multiple-parameter generics having the same TypeUuid (#6633)
# Objective

- Fixes #5432 
- Fixes #6680

## Solution

- move code responsible for generating the `impl TypeUuid` from `type_uuid_derive` into a new function, `gen_impl_type_uuid`.
- this allows the new proc macro, `impl_type_uuid`, to call the code for generation.
- added struct `TypeUuidDef` and implemented `syn::Parse` to allow parsing of the input for the new macro.
- finally, used the new macro `impl_type_uuid` to implement `TypeUuid` for the standard library (in `crates/bevy_reflect/src/type_uuid_impl.rs`).
- fixes #6680 by doing a wrapping add of the param's index to its `TYPE_UUID`

Co-authored-by: dis-da-moe <84386186+dis-da-moe@users.noreply.github.com>
2023-02-16 17:09:44 +00:00

89 lines
2.8 KiB
Rust

use crate::{
prelude::{FromWorld, QueryState},
query::{ReadOnlyWorldQuery, WorldQuery},
system::{Local, SystemMeta, SystemParam, SystemState},
world::World,
};
use bevy_utils::all_tuples;
use bevy_utils::synccell::SyncCell;
pub trait ExclusiveSystemParam: Sized {
type State: Send + Sync + 'static;
type Item<'s>: ExclusiveSystemParam<State = Self::State>;
fn init(world: &mut World, system_meta: &mut SystemMeta) -> Self::State;
fn get_param<'s>(state: &'s mut Self::State, system_meta: &SystemMeta) -> Self::Item<'s>;
}
pub type ExclusiveSystemParamItem<'s, P> = <P as ExclusiveSystemParam>::Item<'s>;
impl<'a, Q: WorldQuery + 'static, F: ReadOnlyWorldQuery + 'static> ExclusiveSystemParam
for &'a mut QueryState<Q, F>
{
type State = QueryState<Q, F>;
type Item<'s> = &'s mut QueryState<Q, F>;
fn init(world: &mut World, _system_meta: &mut SystemMeta) -> Self::State {
QueryState::new(world)
}
fn get_param<'s>(state: &'s mut Self::State, _system_meta: &SystemMeta) -> Self::Item<'s> {
state
}
}
impl<'a, P: SystemParam + 'static> ExclusiveSystemParam for &'a mut SystemState<P> {
type State = SystemState<P>;
type Item<'s> = &'s mut SystemState<P>;
fn init(world: &mut World, _system_meta: &mut SystemMeta) -> Self::State {
SystemState::new(world)
}
fn get_param<'s>(state: &'s mut Self::State, _system_meta: &SystemMeta) -> Self::Item<'s> {
state
}
}
impl<'_s, T: FromWorld + Send + 'static> ExclusiveSystemParam for Local<'_s, T> {
type State = SyncCell<T>;
type Item<'s> = Local<'s, T>;
fn init(world: &mut World, _system_meta: &mut SystemMeta) -> Self::State {
SyncCell::new(T::from_world(world))
}
fn get_param<'s>(state: &'s mut Self::State, _system_meta: &SystemMeta) -> Self::Item<'s> {
Local(state.get())
}
}
macro_rules! impl_exclusive_system_param_tuple {
($($param: ident),*) => {
#[allow(unused_variables)]
#[allow(non_snake_case)]
impl<$($param: ExclusiveSystemParam),*> ExclusiveSystemParam for ($($param,)*) {
type State = ($($param::State,)*);
type Item<'s> = ($($param::Item<'s>,)*);
#[inline]
fn init(_world: &mut World, _system_meta: &mut SystemMeta) -> Self::State {
(($($param::init(_world, _system_meta),)*))
}
#[inline]
#[allow(clippy::unused_unit)]
fn get_param<'s>(
state: &'s mut Self::State,
system_meta: &SystemMeta,
) -> Self::Item<'s> {
let ($($param,)*) = state;
($($param::get_param($param, system_meta),)*)
}
}
};
}
all_tuples!(impl_exclusive_system_param_tuple, 0, 16, P);