lyra-engine/lyra-ecs/src/world.rs

691 lines
25 KiB
Rust

use std::{any::TypeId, collections::HashMap, ptr::NonNull};
use atomic_refcell::{AtomicRef, AtomicRefMut};
use crate::{archetype::{Archetype, ArchetypeId}, bundle::Bundle, query::{dynamic::DynamicView, AsQuery, Query, ViewIter, ViewOne, ViewState}, resource::ResourceData, ComponentInfo, DynTypeId, DynamicBundle, Entities, Entity, ResourceObject, Tick, TickTracker};
/// The id of the entity for the Archetype.
///
/// The Archetype uses this as the index in the component columns
#[derive(Debug, Copy, Clone, PartialEq, Eq, Hash)]
pub struct ArchetypeEntityId(pub u64);
#[derive(Debug, Copy, Clone, PartialEq, Eq, Hash)]
pub struct Record {
pub id: ArchetypeId,
pub index: ArchetypeEntityId,
}
#[derive(Clone)]
pub struct World {
pub(crate) archetypes: HashMap<ArchetypeId, Archetype>,
next_archetype_id: ArchetypeId,
resources: HashMap<TypeId, ResourceData>,
tracker: TickTracker,
pub(crate) entities: Entities,
}
impl Default for World {
fn default() -> Self {
Self {
archetypes: HashMap::new(),
next_archetype_id: ArchetypeId(0),
resources: HashMap::new(),
tracker: TickTracker::new(),
entities: Entities::default(),
}
}
}
impl World {
pub fn new() -> Self {
Self::default()
}
/// Reserves an entity in the world
pub fn reserve_entity(&mut self) -> Entity {
self.entities.reserve()
}
pub fn spawn<B>(&mut self, bundle: B) -> Entity
where
B: Bundle
{
let new_entity = self.reserve_entity();
self.spawn_into(new_entity, bundle);
new_entity
}
/// Spawn the components into a reserved entity. Only do this with entities that
/// were reserved with [`World::reserve_entity`].
///
/// # Safety
/// Do not use this method with an entity that is currently alive, it WILL cause undefined behavior.
pub fn spawn_into<B>(&mut self, entity: Entity, bundle: B)
where
B: Bundle
{
let bundle_types = bundle.type_ids();
let tick = self.tick();
// try to find an archetype
let archetype = self.archetypes
.values_mut()
.find(|a| a.is_archetype_for(&bundle_types));
if let Some(archetype) = archetype {
// make at just one check to ensure you're not spawning twice
debug_assert!(!archetype.entity_ids.contains_key(&entity),
"You attempted to spawn components into an entity that already exists!");
let arche_idx = archetype.add_entity(entity, bundle, &tick);
// Create entity record and store it
let record = Record {
id: archetype.id(),
index: arche_idx,
};
self.entities.insert_entity_record(entity, record);
}
// create a new archetype if one isn't found
else {
// create archetype
let new_arch_id = self.next_archetype_id.increment();
let mut archetype = Archetype::from_bundle_info(new_arch_id, bundle.info());
let entity_arch_id = archetype.add_entity(entity, bundle, &tick);
// store archetype
self.archetypes.insert(new_arch_id, archetype);
// Create entity record and store it
let record = Record {
id: new_arch_id,
// this is the first entity in the archetype
index: entity_arch_id,
};
self.entities.insert_entity_record(entity, record);
}
}
/// Despawn an entity from the World
pub fn despawn(&mut self, entity: Entity) {
// Tick the tracker if the entity is spawned. This is done here instead of the `if let`
// below due to the borrow checker complaining about multiple mutable borrows to self.
let tick = if self.entities.arch_index.contains_key(&entity.id) {
Some(self.tick())
} else { None };
if let Some(record) = self.entities.arch_index.get_mut(&entity.id) {
let tick = tick.unwrap();
let arch = self.archetypes.get_mut(&record.id).unwrap();
if let Some((moved, new_index)) = arch.remove_entity(entity, &tick) {
// replace the archetype index of the moved index with its new index.
self.entities.arch_index.get_mut(&moved.id).unwrap().index = new_index;
}
}
}
/// Insert a component bundle into an existing entity.
///
/// If the components are already existing on the entity, they will be updated, else the
/// entity will be moved to a different Archetype that can store the entity. That may
/// involve creating a new Archetype.
pub fn insert<B>(&mut self, entity: Entity, bundle: B)
where
B: Bundle
{
let tick = self.tick();
let record = self.entities.entity_record(entity).unwrap();
let current_arch = self.archetypes.get(&record.id).unwrap();
let current_arch_len = current_arch.len();
let mut contains_all = true;
for id in bundle.type_ids() {
contains_all = contains_all && current_arch.get_column(id).is_some();
}
if contains_all {
let current_arch = self.archetypes.get_mut(&record.id).unwrap();
let entry_idx = *current_arch.entity_indexes()
.get(&entity).unwrap();
bundle.take(|ptr, id, _info| {
let col = current_arch.get_column_mut(id).unwrap();
unsafe { col.set_at(entry_idx.0 as _, ptr, tick) };
});
return;
}
// contains the type ids for the old component columns + the ids for the new components
let mut combined_column_types: Vec<DynTypeId> = current_arch.columns.iter().map(|c| c.info.type_id()).collect();
combined_column_types.extend(bundle.type_ids());
// contains the ComponentInfo for the old component columns + the info for the new components
let mut combined_column_infos: Vec<ComponentInfo> = current_arch.columns.iter().map(|c| c.info).collect();
combined_column_infos.extend(bundle.info());
// pointers only for the old columns
let old_columns: Vec<(NonNull<u8>, ComponentInfo)> = current_arch.columns.iter()
.map(|c| unsafe { (NonNull::new_unchecked(c.borrow_ptr().as_ptr()), c.info) })
.collect();
if let Some(arch) = self.archetypes.values_mut().find(|a| a.is_archetype_for(&combined_column_types)) {
let mut dbun = DynamicBundle::new();
// move old entity components into new archetype columns
for (col_ptr, col_info) in old_columns.into_iter() {
unsafe {
let ptr = NonNull::new_unchecked(col_ptr.as_ptr()
.add(record.index.0 as usize * col_info.layout().size()));
dbun.push_unknown(ptr, col_info);
}
}
dbun.push_bundle(bundle);
let res_index = arch.add_entity(entity, dbun, &tick);
arch.ensure_synced();
let new_record = Record {
id: arch.id(),
index: res_index,
};
self.entities.insert_entity_record(entity, new_record);
} else {
if current_arch_len == 1 {
// if this entity is the only entity for this archetype, add more columns to it
let current_arch = self.archetypes.get_mut(&record.id).unwrap();
current_arch.extend(&tick, vec![bundle]);
return;
}
let new_arch_id = self.next_archetype_id.increment();
let mut archetype = Archetype::from_bundle_info(new_arch_id, combined_column_infos);
let mut dbun = DynamicBundle::new();
for (column_ptr, column_info) in old_columns.into_iter() {
unsafe {
// ptr of component for the entity
let comp_ptr = NonNull::new_unchecked(column_ptr.as_ptr()
.add(record.index.0 as usize * column_info.layout().size()));
dbun.push_unknown(comp_ptr, column_info);
}
}
dbun.push_bundle(bundle);
let entity_arch_id = archetype.add_entity(entity, dbun, &tick);
self.archetypes.insert(new_arch_id, archetype);
// Create entity record and store it
let record = Record {
id: new_arch_id,
index: entity_arch_id,
};
self.entities.insert_entity_record(entity, record);
}
let current_arch = self.archetypes.get_mut(&record.id).unwrap();
if let Some((en, enar)) = current_arch.remove_entity(entity, &tick) {
let rec = Record {
id: current_arch.id(),
index: enar
};
self.entities.insert_entity_record(en, rec);
}
current_arch.ensure_synced();
}
/// A method used for debugging implementation details of the ECS.
///
/// Here's an example of the output:
/// ```nobuild
/// Entities
/// 1 in archetype 0 at 0
/// 0 in archetype 1 at 0
/// 2 in archetype 0 at 1
/// 3 in archetype 2 at 0
/// Arch 1 -- 1 entities
/// Col 175564825027445222460146453544114453753
/// 0: 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 128 63 0 0 128 63 0 0 128 63 0 0 128 63 78 86 0 0
/// Col 162279302565774655543278578489329315472
/// 0: 0 0 32 65 0 0 32 65 0 0 32 65 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 128 63 0 0 128 63 0 0 128 63 0 0 128 63 0 0 0 0
/// Col 24291284537013640759061027938209843602
/// 0: 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
/// Arch 2 -- 1 entities
/// Col 175564825027445222460146453544114453753
/// 0: 0 0 0 0 0 0 0 0 0 0 0 0 237 127 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 128 63 0 0 128 63 0 0 128 63 0 0 128 63 78 86 0 0
/// Col 162279302565774655543278578489329315472
/// 0: 0 0 76 66 0 0 170 66 0 0 136 65 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 128 63 0 0 128 63 0 0 128 63 0 0 128 63 0 0 0 0
/// Col 142862377085187052737282554588643015580
/// 0: 2 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
/// Arch 0 -- 2 entities
/// Col 175564825027445222460146453544114453753
/// 0: 0 0 0 0 0 0 0 0 0 0 0 0 0 0 32 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 128 63 0 0 128 63 0 0 128 63 0 0 128 63 0 0 0 0
/// 1: 0 0 0 0 0 0 0 0 0 0 0 0 237 127 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 128 63 0 0 128 63 0 0 128 63 0 0 128 63 78 86 0 0
/// Col 162279302565774655543278578489329315472
/// 0: 0 0 112 65 0 0 112 65 0 0 112 65 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 128 63 0 0 128 63 0 0 128 63 0 0 128 63 0 0 0 0
/// 1: 0 0 27 67 0 0 184 65 0 0 192 64 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 128 63 0 0 128 63 0 0 128 63 0 0 128 63 0 0 0 0
/// Col 142862377085187052737282554588643015580
/// 0: 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
/// 1: 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
/// Col 24291284537013640759061027938209843602
/// 0: 2 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
/// 1: 3 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
/// Arch 3 -- 0 entities
/// Col 175564825027445222460146453544114453753
/// Col 162279302565774655543278578489329315472
/// ```
///
/// This output prints all Entity ids, the archetype they're in, and the index that they're
/// in inside of the archetype. Additionally, the archetypes are printing, including their
/// columns type ids, and the contents of the type ids. This output can be used to debug
/// the contents of entities inside the archetypes.
///
/// Below is a template of the output:
/// ```nobuild
/// Entities
/// %ENTITY_ID% in archetype %ARCHETYPE_ID% at %INDEX%
/// Arch ID -- %ARCHETYPE_LEN% entities
/// %FOR EACH COL%
/// Col COLUMN_COMPONENT_TYPE_ID
/// %FOR EACH ENTITY%
/// %ENTITY_INDEX%: %COMPONENT_BYTES%
/// ```
/// If the template above doesn't help you in understanding the output, read the source code
/// of the function. The source code is pretty simple.
pub fn debug_print_world(&self) {
println!("Entities");
for (en, rec) in &self.entities.arch_index {
println!(" {} in archetype {} at {}", en.0, rec.id.0, rec.index.0);
}
for arch in self.archetypes.values() {
println!("Arch {} -- {} entities", arch.id().0, arch.len());
for col in &arch.columns {
// no clue if doing this is stable, but this is a debug function so :shrug:
let tyid: u128 = unsafe { std::mem::transmute(col.info.type_id().as_rust()) };
println!(" Col {}", tyid);
for en in 0..col.len {
// get the ptr starting at the component
let p = col.borrow_ptr();
let p = unsafe { p.as_ptr().add(en * col.info.layout().size()) };
print!(" {}: ", en);
// print each byte of the component
for i in 0..col.info.layout().size() {
let d = unsafe { *p.add(i) };
print!("{} ", d);
}
println!();
}
}
}
}
pub fn entity_archetype(&self, entity: Entity) -> Option<&Archetype> {
self.entities.entity_record(entity)
.and_then(|record| self.archetypes.get(&record.id))
}
pub fn entity_archetype_mut(&mut self, entity: Entity) -> Option<&mut Archetype> {
self.entities.entity_record(entity)
.and_then(|record| self.archetypes.get_mut(&record.id))
}
/// View into the world for a set of entities that satisfy the queries.
pub fn view<Q: AsQuery>(&self) -> ViewState<Q::Query, ()> {
self.filtered_view::<Q, ()>()
}
/// View into the world for a set of entities that satisfy the query and the filter.
pub fn filtered_view<Q: AsQuery, F: AsQuery>(&self) -> ViewState<Q::Query, F::Query> {
let archetypes = self.archetypes.values().collect();
ViewState::<Q::Query, F::Query>::new(self, Q::Query::new(), F::Query::new(), archetypes)
}
/// View into the world for a set of entities that satisfy the queries.
pub fn view_iter<Q: AsQuery>(&self) -> ViewIter<Q::Query, ()> {
let archetypes = self.archetypes.values().collect();
let v = ViewState::new(self, Q::Query::new(), (), archetypes);
v.into_iter()
}
/// View into the world for a set of entities that satisfy the queries.
pub fn filtered_view_iter<Q: AsQuery, F: AsQuery>(&self) -> ViewIter<Q::Query, F::Query> {
let archetypes = self.archetypes.values().collect();
let v = ViewState::new(self, Q::Query::new(), F::Query::new(), archetypes);
v.into_iter()
}
pub fn dynamic_view(&self) -> DynamicView {
DynamicView::new(self)
}
pub fn view_one<T: AsQuery>(&self, entity: Entity) -> ViewOne<T::Query> {
ViewOne::new(self, entity.id, T::Query::new())
}
//pub fn view_one(&self, entity: EntityId) ->
pub fn add_resource<T: ResourceObject>(&mut self, data: T) {
self.resources.insert(TypeId::of::<T>(), ResourceData::new(data));
}
pub fn add_resource_default<T: ResourceObject + Default>(&mut self) {
self.resources.insert(TypeId::of::<T>(), ResourceData::new(T::default()));
}
/// Get a resource from the world, or insert it into the world with the provided
/// `fn` and return it.
pub fn get_resource_or_else<T: ResourceObject, F>(&mut self, f: F) -> AtomicRefMut<T>
where
F: Fn() -> T + 'static
{
self.resources.entry(TypeId::of::<T>())
.or_insert_with(|| ResourceData::new(f()))
.get_mut()
}
/// Get a resource from the world, or insert it into the world as its default.
pub fn get_resource_or_default<T: ResourceObject + Default>(&mut self) -> AtomicRefMut<T>
{
self.resources.entry(TypeId::of::<T>())
.or_insert_with(|| ResourceData::new(T::default()))
.get_mut()
}
/// Gets a resource from the World.
///
/// Will panic if the resource is not in the world. See [`World::try_get_resource`] for
/// a function that returns an option.
pub fn get_resource<T: ResourceObject>(&self) -> AtomicRef<T> {
self.resources.get(&TypeId::of::<T>())
.expect(&format!("World is missing resource of type '{}'", std::any::type_name::<T>()))
.get()
}
/// Returns boolean indicating if the World contains a resource of type `T`.
pub fn has_resource<T: ResourceObject>(&self) -> bool {
self.resources.contains_key(&TypeId::of::<T>())
}
/// Attempts to get a resource from the World.
///
/// Returns `None` if the resource was not found.
pub fn try_get_resource<T: ResourceObject>(&self) -> Option<AtomicRef<T>> {
self.resources.get(&TypeId::of::<T>())
.and_then(|r| r.try_get())
}
/// Gets a mutable borrow of a resource from the World.
///
/// Will panic if the resource is not in the world. See [`World::try_get_resource_mut`] for
/// a function that returns an option.
pub fn get_resource_mut<T: ResourceObject>(&self) -> AtomicRefMut<T> {
self.resources.get(&TypeId::of::<T>())
.expect(&format!("World is missing resource of type '{}'", std::any::type_name::<T>()))
.get_mut()
}
/// Attempts to get a mutable borrow of a resource from the World.
///
/// Returns `None` if the resource was not found.
pub fn try_get_resource_mut<T: ResourceObject>(&self) -> Option<AtomicRefMut<T>> {
self.resources.get(&TypeId::of::<T>())
.and_then(|r| r.try_get_mut())
}
/// Increments the TickTracker which is used for tracking changes to components.
///
/// Most users wont need to call this manually, its done for you through queries and views.
pub fn tick(&self) -> Tick {
self.tracker.tick()
}
/// Gets the current tick that the world is at.
///
/// See [`TickTracker`]
pub fn current_tick(&self) -> Tick {
self.tracker.current()
}
pub fn tick_tracker(&self) -> &TickTracker {
&self.tracker
}
/// Attempts to find a resource in the world and returns a NonNull pointer to it
pub unsafe fn try_get_resource_ptr<T: ResourceObject>(&self) -> Option<NonNull<T>> {
self.resources.get(&TypeId::of::<T>())
.map(|d| unsafe { NonNull::new_unchecked(d.data.as_ptr() as *mut T) })
}
pub fn archetype_count(&self) -> usize {
self.archetypes.len()
}
}
// TODO: Ensure that all non-send resources are only accessible on the main thread.
unsafe impl Send for World {}
unsafe impl Sync for World {}
#[cfg(test)]
mod tests {
use crate::{query::TickOf, tests::{Vec2, Vec3}, Entity};
use super::World;
struct SimpleCounter(i32);
#[test]
fn spawning_entity() {
let mut world = World::new();
let _e = world.spawn((Vec2 {
x: 10.0,
y: 15.0,
}, ));
}
#[test]
fn world_view_entities() {
let mut world = World::new();
world.spawn((Vec2 {
x: 10.0,
y: 15.0,
}, ));
world.spawn((Vec2 {
x: 152.0,
y: 3585.0,
}, ));
world.spawn((Vec2 {
x: 235.0,
y: 734.0,
}, ));
let mut count = 0;
for pos in world.view_iter::<&Vec2>() {
println!("Found entity at {:?}", pos);
count += 1;
}
assert!(count == 3);
}
#[test]
fn despawn_entity() {
let mut world = World::new();
world.spawn((Vec2::rand(),));
let middle_en = world.spawn((Vec2::rand(),));
let last_en = world.spawn((Vec2::rand(),));
world.despawn(middle_en);
let record = world.entities.entity_record(last_en).unwrap();
assert_eq!(record.index.0, 1);
}
#[test]
fn simple_resource() {
let mut world = World::new();
{
let counter = SimpleCounter(0);
world.add_resource(counter);
}
let counter = world.get_resource::<SimpleCounter>();
assert_eq!(counter.0, 0);
drop(counter);
let mut counter = world.get_resource_mut::<SimpleCounter>();
counter.0 += 4582;
drop(counter);
assert!(world.try_get_resource::<u32>().is_none());
}
#[test]
fn resource_multi_borrow() {
let mut world = World::new();
let counter = SimpleCounter(4582);
world.add_resource(counter);
// test multiple borrows at the same time
let counter = world.get_resource::<SimpleCounter>();
assert_eq!(counter.0, 4582);
let counter2 = world.get_resource::<SimpleCounter>();
assert_eq!(counter.0, 4582);
assert_eq!(counter2.0, 4582);
}
#[test]
fn resource_one_mutable_borrow() {
let mut world = World::new();
{
let counter = SimpleCounter(4582);
world.add_resource(counter);
}
// test that its only possible to get a single mutable borrow
let counter = world.get_resource_mut::<SimpleCounter>();
assert_eq!(counter.0, 4582);
assert!(world.try_get_resource_mut::<SimpleCounter>().is_none());
assert_eq!(counter.0, 4582);
}
#[test]
fn insert_into_existing_archetype() {
let mut world = World::new();
let e = world.spawn((Vec2::rand(),));
world.spawn((Vec2::rand(),Vec3::rand()));
world.insert(e, (Vec3::rand(),));
assert!(world.view_one::<&Vec3>(e).get().is_some())
}
#[test]
fn insert_into_new_archetype() {
let mut world = World::new();
let e = world.spawn((Vec2::rand(),));
world.insert(e, (Vec3::rand(),));
assert!(world.view_one::<&Vec3>(e).get().is_some())
}
#[test]
fn insert_multiple_times() {
let v2s = &[Vec2::rand(), Vec2::rand(), Vec2::rand()];
let v3s = &[Vec3::rand(), Vec3::rand(), Vec3::rand()];
let mut world = World::new();
let e1 = world.spawn(v2s[0]);
let e2 = world.spawn(v2s[1]);
let e3 = world.spawn(v2s[2]);
println!("Spawned entities");
let ev2 = world.view_one::<&Vec2>(e2).get()
.expect("Failed to find Vec2 and Vec3 on inserted entity!");
assert_eq!(*ev2, v2s[1]);
drop(ev2);
let insert_and_assert = |world: &mut World, e: Entity, v2: Vec2, v3: Vec3| {
println!("inserting entity");
world.insert(e, (v3,));
println!("inserted entity");
let (ev2, ev3) = world.view_one::<(&Vec2, &Vec3)>(e).get()
.expect("Failed to find Vec2 and Vec3 on inserted entity!");
assert_eq!(*ev2, v2);
assert_eq!(*ev3, v3);
};
insert_and_assert(&mut world, e2, v2s[1], v3s[1]);
println!("Entity 2 is good");
insert_and_assert(&mut world, e3, v2s[2], v3s[2]);
println!("Entity 3 is good");
assert_eq!(world.archetypes.len(), 2);
println!("No extra archetypes were created");
insert_and_assert(&mut world, e1, v2s[0], v3s[0]);
println!("Entity 1 is good");
}
#[test]
fn view_one() {
let v = Vec2::rand();
let mut world = World::new();
let e = world.spawn((v,));
let view = world.view_one::<&Vec2>(e);
assert_eq!(*view.get().unwrap(), v);
}
#[test]
fn view_change_tracking() {
let mut world = World::new();
println!("spawning");
world.spawn((Vec2::new(10.0, 10.0),));
world.spawn((Vec2::new(5.0, 5.0),));
println!("spawned");
for mut v in world.view_iter::<&mut Vec2>() {
v.y += 50.0;
println!("Moved v to {:?}", v);
}
let world_tick = world.current_tick();
println!("The world tick is {}", *world_tick);
for (v, tick) in world.view_iter::<(&Vec2, TickOf<Vec2>)>() {
println!("Is at {:?}, it was changed at {}", v, *tick);
assert!(v.y > 50.0);
assert!(tick >= world_tick);
}
}
/// Tests replacing components using World::insert
#[test]
fn entity_insert_replace() {
let mut world = World::new();
let first = world.spawn((Vec2::new(10.0, 10.0),));
let second = world.spawn((Vec2::new(5.0, 5.0),));
world.insert(first, Vec2::new(50.0, 50.0));
let pos = world.view_one::<&mut Vec2>(first).get().unwrap();
assert_eq!(*pos, Vec2::new(50.0, 50.0));
drop(pos);
let pos = world.view_one::<&mut Vec2>(second).get().unwrap();
assert_eq!(*pos, Vec2::new(5.0, 5.0));
}
}