SeanOMik
/
lyra-engine
1
0
Fork 0
Code Issues 5 Pull Requests Actions Packages Projects Releases Wiki Activity

Enforce single mutable borrows of component columns

This commit is contained in:
SeanOMik 2023-11-27 22:24:29 -05:00
parent 4c0b517127
commit e8e2bc0c24
Signed by: SeanOMik
GPG Key ID: 568F326C7EB33ACB
5 changed files with 148 additions and 63 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

1
lyra-ecs/Cargo.toml
View File

@ -7,6 +7,5 @@ edition = "2021"
[dependencies]
[dev-dependencies]
rand = "0.8.5" # used for tests

4
lyra-ecs/README.md
View File

@ -12,11 +12,11 @@ I couldn't find anything that fulfilled my needs, specifically an ECS that can s
- [x] Find some way to fill in the gaps in component columns after entities are deleted
* This was done by moving the last entity in the column to the gap that was just removed.
- [x] Grow archetype as it fills up
- [ ] Borrow safety of components inside Archetypes
* Its wonk right now; a component can be borrowed mutably from a non-mutable reference.
- [x] Borrow safety of components inside Archetypes
- [ ] Querying components from archetypes
- [x] Views
- [ ] Mutable views
- [ ] Make it possible so that ONLY `ViewMut` can borrow mutably
- [ ] Resources
- [ ] Relationships (maybe this can be done through queries, idk)
- [ ] Dynamic queries

138
lyra-ecs/src/archetype.rs
View File

@ -1,27 +1,40 @@
use std::{any::TypeId, ptr::{NonNull, self}, alloc::{self, Layout, alloc, dealloc}, mem, collections::HashMap};
use std::{any::TypeId, ptr::{NonNull, self}, alloc::{self, Layout, alloc, dealloc}, mem, collections::HashMap, cell::{RefCell, Ref, RefMut, BorrowError, BorrowMutError}, ops::{DerefMut, Deref}};
use crate::{world::{Entity, ArchetypeEntityId, Record}, bundle::Bundle, component_info::ComponentInfo};
use crate::{world::{Entity, ArchetypeEntityId}, bundle::Bundle, component_info::ComponentInfo};
pub struct ComponentColumn {
pub data: NonNull<u8>,
pub capacity: usize,
data: RefCell<NonNull<u8>>,
len: usize,
capacity: usize,
pub info: ComponentInfo,
pub entry_size: usize,
pub len: usize,
}
impl Drop for ComponentColumn {
fn drop(&mut self) {
let data = self.data.borrow_mut();
let data = data.as_ptr();
unsafe {
// layout of current alloc
let layout = Layout::from_size_align_unchecked(self.info.layout.size() * self.capacity,
self.info.layout.align());
dealloc(data, layout);
}
}
}
#[allow(dead_code)]
impl ComponentColumn {
/// Creates an invalid component column. Do not attempt to use it.
pub unsafe fn dangling() -> Self {
/* pub unsafe fn dangling() -> Self {
ComponentColumn {
data: NonNull::dangling(),
data: RefCell::
capacity: 0,
info: ComponentInfo::new::<()>(),
entry_size: 0,
len: 0,
}
}
} */
pub unsafe fn alloc(component_layout: Layout, capacity: usize) -> NonNull<u8> {
let new_layout = Layout::from_size_align(
@ -39,12 +52,10 @@ impl ComponentColumn {
pub unsafe fn new(info: ComponentInfo, capacity: usize) -> Self {
let data = ComponentColumn::alloc(info.layout, capacity);
let size = info.layout.size();
Self {
data,
data: RefCell::new(data),
capacity,
info,
entry_size: size,
len: 0,
}
}
@ -56,8 +67,12 @@ impl ComponentColumn {
/// This column must have space to fit the component, if it does not have room it will panic.
pub unsafe fn set_at(&mut self, entity_index: usize, comp_src: NonNull<u8>) {
assert!(entity_index < self.capacity);
let dest = NonNull::new_unchecked(self.data.as_ptr().add(entity_index * self.entry_size));
ptr::copy_nonoverlapping(comp_src.as_ptr(), dest.as_ptr(), self.entry_size);
let mut data = self.data.borrow_mut();
let data = data.deref_mut();
let dest = NonNull::new_unchecked(data.as_ptr().add(entity_index * self.info.layout.size()));
ptr::copy_nonoverlapping(comp_src.as_ptr(), dest.as_ptr(), self.info.layout.size());
self.len += 1;
}
@ -67,8 +82,11 @@ impl ComponentColumn {
///
/// This column MUST have the entity. If it does not, it WILL NOT panic and will cause UB.
pub unsafe fn get<T>(&self, entity_index: usize) -> &T {
let ptr = NonNull::new_unchecked(self.data.as_ptr()
.add(entity_index * self.entry_size))
let data = self.data.borrow();
let data = data.deref();
let ptr = NonNull::new_unchecked(data.as_ptr()
.add(entity_index * self.info.layout.size()))
.cast();
&*ptr.as_ptr()
}
@ -79,9 +97,12 @@ impl ComponentColumn {
///
/// This column must have the entity.
pub unsafe fn get_mut<T>(&mut self, entity_index: usize) -> &mut T {
let p = self.data.as_ptr()
let mut data = self.data.borrow_mut();
let data = data.deref_mut();
let p = data.as_ptr()
.cast::<T>()
.add(entity_index * self.entry_size);
.add(entity_index * self.info.layout.size());
&mut *p
}
@ -95,31 +116,46 @@ impl ComponentColumn {
/// Will panic if `new_capacity` is less than the current capacity of the column.
pub unsafe fn grow(&mut self, new_capacity: usize) {
assert!(new_capacity > self.capacity);
let mut new_ptr = Self::alloc(self.info.layout, new_capacity);
ptr::copy_nonoverlapping(self.data.as_ptr(), new_ptr.as_ptr(), self.capacity * self.entry_size);
let mut data = self.data.borrow_mut();
//let data = data.deref_mut();
let mut new_ptr = Self::alloc(self.info.layout, new_capacity);
if self.len > 0 {
ptr::copy_nonoverlapping(data.as_ptr(), new_ptr.as_ptr(), self.len * self.info.layout.size());
}
// dont attempt to free if we weren't able to store anything anyway
if self.capacity != 0 {
let old_layout = Layout::from_size_align_unchecked(
self.info.layout.size().checked_mul(self.capacity).unwrap(),
self.info.layout.align()
);
mem::swap(&mut self.data, &mut new_ptr); // 'new_ptr' is now the old pointer
mem::swap(data.deref_mut(), &mut new_ptr);
dealloc(new_ptr.as_ptr(), old_layout);
} else {
*data = new_ptr;
}
self.capacity = new_capacity;
}
/// Removes a component from the column, freeing it, and returning the old index of the entity that took its place in the column.
pub unsafe fn remove_component(&mut self, entity_index: usize) -> Option<usize> {
let mut old_comp_ptr = NonNull::new_unchecked(self.data.as_ptr()
.add(entity_index * self.entry_size));
let mut data = self.data.borrow_mut();
let data = data.deref_mut();
let mut old_comp_ptr = NonNull::new_unchecked(data.as_ptr()
.add(entity_index * self.info.layout.size()));
let moved_index = if entity_index != self.len - 1 {
let moved_index = self.len - 1;
let mut new_comp_ptr = NonNull::new_unchecked(self.data.as_ptr()
.add(moved_index * self.entry_size));
let mut new_comp_ptr = NonNull::new_unchecked(data.as_ptr()
.add(moved_index * self.info.layout.size()));
ptr::copy_nonoverlapping(new_comp_ptr.as_ptr(), old_comp_ptr.as_ptr(), self.entry_size);
ptr::copy_nonoverlapping(new_comp_ptr.as_ptr(), old_comp_ptr.as_ptr(), self.info.layout.size());
mem::swap(&mut old_comp_ptr, &mut new_comp_ptr); // new_comp_ptr is now the old ptr
Some(moved_index)
@ -129,6 +165,22 @@ impl ComponentColumn {
moved_index
}
pub fn borrow_ptr<'a>(&'a self) -> Ref<'a, NonNull<u8>> {
self.data.borrow()
}
pub fn borrow_mut_ptr<'a>(&'a self) -> RefMut<'a, NonNull<u8>> {
self.data.borrow_mut()
}
pub fn try_borrow_ptr<'a>(&'a self) -> Result<Ref<'a, NonNull<u8>>, BorrowError> {
self.data.try_borrow()
}
pub fn try_borrow_mut_ptr<'a>(&'a self) -> Result<RefMut<'a, NonNull<u8>>, BorrowMutError> {
self.data.try_borrow_mut()
}
}
#[derive(Debug, Copy, Clone, PartialEq, Eq, Hash)]
@ -252,6 +304,8 @@ impl Archetype {
for c in self.columns.iter_mut() {
unsafe { c.grow(new_capacity); }
}
self.capacity = new_capacity;
}
}
@ -353,19 +407,30 @@ mod tests {
assert_eq!(vec3.clone(), b2.1);
}
/// Tests manual growth of archetypes
#[test]
fn column_growth() {
fn archetype_growth() {
let info = (Vec2::new(0.0, 0.0),).info();
let mut a = Archetype::from_bundle_info(super::ArchetypeId(0), info);
a.grow_columns(64);
a.grow_columns(128);
a.grow_columns(256);
}
/// Tests the auto growth of archetypes when adding entities
#[test]
fn auto_archetype_growth() {
let mut rng = rand::thread_rng();
let bundle_count = rng.gen_range(50..150);
let mut bundles = vec![];
let mut bundles: Vec<(Vec2,)> = vec![];
bundles.reserve(bundle_count);
let info = (Vec2::new(0.0, 0.0),).info();
let mut a = Archetype::from_bundle_info(super::ArchetypeId(0), info);
for i in 0..bundle_count {
let c = (Vec2::new(rng.gen_range(10.0..3000.0), rng.gen_range(10.0..3000.0)),);
let c = (Vec2::rand(),);
bundles.push(c);
a.add_entity(
@ -376,6 +441,7 @@ mod tests {
c
);
}
println!("Inserted {} entities", bundle_count);
let col = a.columns.get(0).unwrap();
for i in 0..bundle_count {
@ -386,14 +452,8 @@ mod tests {
#[test]
fn remove_entity() {
let mut rng = rand::thread_rng();
let range = 30.0..1853.0;
let bundles = vec![
( Vec2::new(rng.gen_range(range.clone()), rng.gen_range(range.clone())), ),
( Vec2::new(rng.gen_range(range.clone()), rng.gen_range(range.clone())), ),
( Vec2::new(rng.gen_range(range.clone()), rng.gen_range(range.clone())), )
];
let bundles = vec![Vec2::rand(), Vec2::rand(), Vec2::rand()];
println!("Bundles: {:?}", bundles);
let info = (Vec2::new(0.0, 0.0),).info();
let mut a = Archetype::from_bundle_info(super::ArchetypeId(0), info);
@ -405,7 +465,7 @@ mod tests {
id: EntityId(i as u64),
generation: 0
},
bundles[i],
(bundles[i],),
);
}
@ -424,6 +484,6 @@ mod tests {
// make sure that the entities' component was actually moved in the column
let col = &a.columns[0];
let comp = unsafe { col.get::<Vec2>(1) };
assert_eq!(comp.clone(), bundles[2].0);
assert_eq!(comp.clone(), bundles[2]);
}
}

1
lyra-ecs/src/main.rs
View File

@ -1,4 +1,3 @@
//#![feature(cell_leak)]
use crate::world::World;
mod archetype;

55
lyra-ecs/src/query/borrow.rs
View File

@ -1,10 +1,10 @@
use std::{marker::PhantomData, any::TypeId, ptr::NonNull};
use std::{marker::PhantomData, any::TypeId, ptr::NonNull, cell::{Ref, RefCell, RefMut}};
use super::{Fetch, Query, AsQuery, DefaultQuery};
/// Fetcher for borrowing components from archetypes.
pub struct FetchBorrow<'a, T> {
ptr: NonNull<u8>,
ptr: Option<Ref<'a, NonNull<u8>>>,
size: usize,
_phantom: PhantomData<&'a T>
}
@ -17,14 +17,15 @@ where
fn dangling() -> Self {
FetchBorrow {
ptr: NonNull::dangling(),
ptr: None,
size: 0,
_phantom: PhantomData::default()
}
}
unsafe fn get_item(&mut self, entity: crate::world::ArchetypeEntityId) -> Self::Item {
let ptr = NonNull::new_unchecked(self.ptr.as_ptr()
let ptr = self.ptr.as_ref().unwrap();
let ptr = NonNull::new_unchecked(ptr.as_ptr()
.add(entity.0 as usize * self.size))
.cast();
&*ptr.as_ptr()
@ -68,10 +69,10 @@ where
unsafe fn fetch<'a>(&self, _arch_id: crate::archetype::ArchetypeId, archetype: &'a crate::archetype::Archetype) -> Self::Fetch<'a> {
let col = archetype.columns.iter().find(|c| c.info.type_id == self.type_id)
.expect("You ignored 'can_visit_archetype'!");
let col_data = col.data;
let col_data = col.borrow_ptr();
FetchBorrow {
ptr: NonNull::new_unchecked(col_data.as_ptr()),
ptr: Some(col_data),
size: col.info.layout.size(),
_phantom: PhantomData,
}
@ -100,7 +101,7 @@ impl<T: 'static> DefaultQuery for &T {
/// A fetcher for mutably borrowing components from archetypes.
pub struct FetchBorrowMut<'a, T> {
ptr: NonNull<u8>,
ptr: Option<RefMut<'a, NonNull<u8>>>,
size: usize,
_phantom: PhantomData<&'a T>
}
@ -113,14 +114,15 @@ where
fn dangling() -> Self {
FetchBorrowMut {
ptr: NonNull::dangling(),
ptr: None,
size: 0,
_phantom: PhantomData::default()
}
}
unsafe fn get_item(&mut self, entity: crate::world::ArchetypeEntityId) -> Self::Item {
let ptr = NonNull::new_unchecked(self.ptr.as_ptr()
let ptr = self.ptr.as_ref().unwrap();
let ptr = NonNull::new_unchecked(ptr.as_ptr()
.add(entity.0 as usize * self.size))
.cast();
&mut *ptr.as_ptr()
@ -164,10 +166,10 @@ where
unsafe fn fetch<'a>(&self, _arch_id: crate::archetype::ArchetypeId, archetype: &'a crate::archetype::Archetype) -> Self::Fetch<'a> {
let col = archetype.columns.iter().find(|c| c.info.type_id == self.type_id)
.expect("You ignored 'can_visit_archetype'!");
let col_data = col.data;
let col_data = col.borrow_mut_ptr();
FetchBorrowMut {
ptr: NonNull::new_unchecked(col_data.as_ptr()),
ptr: Some(col_data),
size: col.info.layout.size(),
_phantom: PhantomData,
}
@ -196,11 +198,11 @@ impl<T: 'static> DefaultQuery for &mut T {
#[cfg(test)]
mod tests {
use std::any::TypeId;
use std::{any::TypeId, mem::size_of, marker::PhantomData};
use crate::{world::World, archetype::Archetype, query::View, tests::Vec2};
use crate::{world::{World, Entity, EntityId}, archetype::{Archetype, ArchetypeId}, query::View, tests::Vec2, bundle::Bundle};
use super::{QueryBorrow, QueryBorrowMut};
use super::{QueryBorrow, QueryBorrowMut, FetchBorrowMut};
/// Creates a world with two entities, one at Vec(10, 50) and
/// the other at Vec2(25, 30).
@ -262,4 +264,29 @@ mod tests {
}
println!("They were modified!");
}
#[test]
fn only_one_mutable_borrow() {
let info = (Vec2::new(0.0, 0.0),).info();
let mut a = Archetype::from_bundle_info(ArchetypeId(0), info);
for i in 0..10 {
a.add_entity(Entity {
id: EntityId(i),
generation: 0,
}, (Vec2::rand(),));
}
let col = a.columns.iter().find(|c| c.info.type_id == TypeId::of::<Vec2>()).unwrap();
let bmut = FetchBorrowMut::<Vec2> {
ptr: Some(col.borrow_mut_ptr()),
size: size_of::<Vec2>(),
_phantom: PhantomData,
};
assert!(col.try_borrow_mut_ptr().is_err());
drop(bmut);
assert!(col.try_borrow_mut_ptr().is_ok());
}
}