From a44e663eb6d4aaf567dd35f2676014ba5aaa9e00 Mon Sep 17 00:00:00 2001
From: HampusM <hampus@hampusmat.com>
Date: Sun, 5 Jan 2025 22:03:34 +0100
Subject: feat(ecs): allow control over component mutability in query

---
 ecs/src/query.rs | 114 ++++++-------------------------------------------------
 1 file changed, 12 insertions(+), 102 deletions(-)

(limited to 'ecs/src/query.rs')

diff --git a/ecs/src/query.rs b/ecs/src/query.rs
index 68964eb..53d4b74 100644
--- a/ecs/src/query.rs
+++ b/ecs/src/query.rs
@@ -9,22 +9,21 @@ use crate::component::storage::{
     Storage as ComponentStorage,
 };
 use crate::component::{
-    Component,
     Metadata as ComponentMetadata,
-    Sequence as ComponentSequence,
+    RefSequence as ComponentRefSequence,
 };
-use crate::lock::{ReadGuard, WriteGuard};
+use crate::lock::ReadGuard;
 use crate::query::options::Options;
 use crate::system::{Param as SystemParam, System};
 use crate::uid::Uid;
-use crate::{EntityComponent, World};
+use crate::World;
 
 pub mod options;
 
 #[derive(Debug)]
 pub struct Query<'world, Comps, OptionsT = ()>
 where
-    Comps: ComponentSequence,
+    Comps: ComponentRefSequence,
 {
     world: &'world World,
     component_storage: ReadGuard<'world, ComponentStorage>,
@@ -33,36 +32,9 @@ where
 
 impl<'world, Comps, OptionsT> Query<'world, Comps, OptionsT>
 where
-    Comps: ComponentSequence,
+    Comps: ComponentRefSequence,
     OptionsT: Options,
 {
-    /// Iterates over the entities matching this query.
-    #[must_use]
-    pub fn iter_mut<'query>(
-        &'query self,
-    ) -> ComponentIterMut<'query, 'world, Comps, QueryEntityIter<'query>>
-    {
-        #[cfg(feature = "debug")]
-        tracing::debug!("Searching for {}", std::any::type_name::<Comps>());
-
-        #[allow(clippy::map_flatten)]
-        ComponentIterMut {
-            world: self.world,
-            entities: self
-                .component_storage
-                .iter_archetypes_with_comps(Comps::metadata())
-                .map(
-                    (|archetype| {
-                        repeat_n(archetype, archetype.entity_cnt())
-                            .zip(archetype.entities())
-                    }) as ComponentIterMapFn,
-                )
-                .flatten()
-                .filter(|(_, entity)| OptionsT::entity_filter(entity.components())),
-            comps_pd: PhantomData,
-        }
-    }
-
     /// Iterates over the entities matching this query.
     #[must_use]
     pub fn iter<'query>(
@@ -158,21 +130,21 @@ where
 impl<'query, 'world, Comps, OptionsT> IntoIterator
     for &'query Query<'world, Comps, OptionsT>
 where
-    Comps: ComponentSequence + 'world,
+    Comps: ComponentRefSequence + 'world,
     OptionsT: Options,
 {
-    type IntoIter = ComponentIterMut<'query, 'world, Comps, QueryEntityIter<'query>>;
-    type Item = Comps::MutRefs<'query>;
+    type IntoIter = ComponentIter<'query, 'world, Comps, QueryEntityIter<'query>>;
+    type Item = Comps::Handles<'query>;
 
     fn into_iter(self) -> Self::IntoIter
     {
-        self.iter_mut()
+        self.iter()
     }
 }
 
 impl<'world, Comps, OptionsT> SystemParam<'world> for Query<'world, Comps, OptionsT>
 where
-    Comps: ComponentSequence,
+    Comps: ComponentRefSequence,
     OptionsT: Options,
 {
     type Input = ();
@@ -204,52 +176,6 @@ type QueryEntityIter<'query> = Filter<
     ComponentIterFilterFn,
 >;
 
-pub struct ComponentIterMut<'query, 'world, Comps, EntityIter>
-where
-    EntityIter: Iterator<Item = (&'query Archetype, &'query ArchetypeEntity)>,
-{
-    world: &'world World,
-    entities: EntityIter,
-    comps_pd: PhantomData<Comps>,
-}
-
-impl<'query, 'world, Comps, EntityIter> Iterator
-    for ComponentIterMut<'query, 'world, Comps, EntityIter>
-where
-    Comps: ComponentSequence + 'world,
-    EntityIter: Iterator<Item = (&'query Archetype, &'query ArchetypeEntity)>,
-    'world: 'query,
-{
-    type Item = Comps::MutRefs<'query>;
-
-    fn next(&mut self) -> Option<Self::Item>
-    {
-        let (archetype, entity) = self.entities.next()?;
-
-        Some(Comps::from_components_mut(
-            entity.components(),
-            |component_uid| archetype.get_index_for_component(component_uid),
-            self.world,
-            lock_component_rw,
-        ))
-    }
-}
-
-fn lock_component_rw(
-    entity_component: &EntityComponent,
-) -> WriteGuard<'_, Box<dyn Component>>
-{
-    entity_component
-        .component
-        .write_nonblock()
-        .unwrap_or_else(|_| {
-            panic!(
-                "Failed to acquire read-write lock to component {}",
-                entity_component.name
-            );
-        })
-}
-
 pub struct ComponentIter<'query, 'world, Comps, EntityIter>
 where
     EntityIter: Iterator<Item = (&'query Archetype, &'query ArchetypeEntity)>,
@@ -262,11 +188,11 @@ where
 impl<'query, 'world, Comps, EntityIter> Iterator
     for ComponentIter<'query, 'world, Comps, EntityIter>
 where
-    Comps: ComponentSequence + 'world,
+    Comps: ComponentRefSequence + 'world,
     EntityIter: Iterator<Item = (&'query Archetype, &'query ArchetypeEntity)>,
     'world: 'query,
 {
-    type Item = Comps::Refs<'query>;
+    type Item = Comps::Handles<'query>;
 
     fn next(&mut self) -> Option<Self::Item>
     {
@@ -276,22 +202,6 @@ where
             entity.components(),
             |component_uid| archetype.get_index_for_component(component_uid),
             self.world,
-            lock_component_ro,
         ))
     }
 }
-
-fn lock_component_ro(
-    entity_component: &EntityComponent,
-) -> ReadGuard<'_, Box<dyn Component>>
-{
-    entity_component
-        .component
-        .read_nonblock()
-        .unwrap_or_else(|_| {
-            panic!(
-                "Failed to acquire read-write lock to component {}",
-                entity_component.name
-            );
-        })
-}
-- 
cgit v1.2.3-18-g5258