Implement Dynamic Systems and Components

Author: zicklag

Cargo.toml

@@ -39,6 +39,9 @@ render = ["bevy_pbr", "bevy_render", "bevy_sprite", "bevy_text", "bevy_ui"]
 png = ["bevy_render/png"]
 hdr = ["bevy_render/hdr"]
 
+# Enable the dynamic systems and components API ( useful for developing scripting solutions )
+dynamic-api = ["bevy_ecs/dynamic-api", "bevy_scene/dynamic-api"]
+
 # Audio format support (MP3 is enabled by default)
 mp3 = ["bevy_audio/mp3"]
 flac = ["bevy_audio/flac"]
@@ -90,6 +93,8 @@ serde = { version = "1", features = ["derive"] }
 log = "0.4"
 ron = "0.6"
 anyhow = "1.0"
+lazy_static = "1.4.0"
+
 
 # bevy (Android)
 [target.'cfg(target_os = "android")'.dependencies]
@@ -216,6 +221,16 @@ path = "examples/ecs/parallel_query.rs"
 name = "hierarchy"
 path = "examples/ecs/hierarchy.rs"
 
+[[example]]
+name = "dynamic_systems"
+path = "examples/ecs/dynamic_systems.rs"
+required-features = ["dynamic-api"]
+
+[[example]]
+name = "dynamic_components"
+path = "examples/ecs/dynamic_components.rs"
+required-features = ["dynamic-api"]
+
 [[example]]
 name = "breakout"
 path = "examples/game/breakout.rs"

crates/bevy_ecs/Cargo.toml

@@ -15,6 +15,7 @@ categories = ["game-engines", "data-structures"]
 
 [features]
 profiler = []
+dynamic-api = ["bevy_hecs/dynamic-api"]
 
 [dependencies]
 bevy_hecs = { path = "hecs", features = ["macros", "serialize"], version = "0.3.0" }

crates/bevy_ecs/hecs/Cargo.toml

@@ -25,6 +25,8 @@ std = []
 # Enables derive(Bundle)
 macros = ["bevy_hecs_macros", "lazy_static"]
 serialize = ["serde"]
+# Enables the dynamic components and systems APIs
+dynamic-api = ["std"]
 
 [dependencies]
 bevy_hecs_macros = { path = "macros", version = "0.3.0", optional = true }

crates/bevy_ecs/hecs/macros/src/lib.rs

@@ -186,7 +186,12 @@ pub fn impl_query_set(_input: TokenStream) -> TokenStream {
         let query_fn = &query_fns[0..query_count];
         let query_fn_mut = &query_fn_muts[0..query_count];
         tokens.extend(TokenStream::from(quote! {
-            impl<#(#lifetime,)* #(#query: HecsQuery,)*> QueryTuple for (#(Query<#lifetime, #query>,)*) {
+            impl<#(#lifetime,)* #(#query: HecsQuery,)*> QueryTuple for (#(Query<#lifetime, #query>,)*)
+            where
+                #(
+                    #query::Fetch: for<'a> Fetch<'a, State = ()>
+                ),*
+            {
                 unsafe fn new(world: &World, component_access: &TypeAccess<ArchetypeComponent>) -> Self {
                     (
                         #(
@@ -200,12 +205,17 @@ pub fn impl_query_set(_input: TokenStream) -> TokenStream {
 
                 fn get_accesses() -> Vec<QueryAccess> {
                     vec![
-                        #(<#query::Fetch as Fetch>::access(),)*
+                        #(<#query::Fetch as Fetch>::access(&()),)*
                     ]
                 }
             }
 
-            impl<#(#lifetime,)* #(#query: HecsQuery,)*> QuerySet<(#(Query<#lifetime, #query>,)*)> {
+            impl<#(#lifetime,)* #(#query: HecsQuery,)*> QuerySet<(#(Query<#lifetime, #query>,)*)>
+            where
+                #(
+                    #query::Fetch: for<'a> Fetch<'a, State = ()>
+                ),*
+            {
                 #(#query_fn)*
                 #(#query_fn_mut)*
             }

crates/bevy_ecs/hecs/src/access.rs

@@ -1,7 +1,7 @@
 use core::{any::TypeId, hash::Hash};
 use std::{boxed::Box, vec::Vec};
 
-use crate::{Archetype, World};
+use crate::{Archetype, ComponentId, World};
 use bevy_utils::HashSet;
 
 #[derive(Debug, Copy, Clone, Ord, PartialOrd, Eq, PartialEq)]
@@ -14,52 +14,53 @@ pub enum Access {
 #[derive(Copy, Clone, Debug, Eq, PartialEq, Hash)]
 pub struct ArchetypeComponent {
     pub archetype_index: u32,
-    pub component: TypeId,
+    pub component: ComponentId,
 }
 
 impl ArchetypeComponent {
     #[inline]
     pub fn new<T: 'static>(archetype_index: u32) -> Self {
         ArchetypeComponent {
             archetype_index,
-            component: TypeId::of::<T>(),
+            component: TypeId::of::<T>().into(),
         }
     }
 
     #[inline]
-    pub fn new_ty(archetype_index: u32, component: TypeId) -> Self {
+    pub fn new_component(archetype_index: u32, component: ComponentId) -> Self {
         ArchetypeComponent {
             archetype_index,
             component,
         }
     }
 }
 
+#[derive(Clone, Debug)]
 pub enum QueryAccess {
     None,
-    Read(TypeId, &'static str),
-    Write(TypeId, &'static str),
+    Read(ComponentId, &'static str),
+    Write(ComponentId, &'static str),
     Optional(Box<QueryAccess>),
-    With(TypeId, Box<QueryAccess>),
-    Without(TypeId, Box<QueryAccess>),
+    With(ComponentId, Box<QueryAccess>),
+    Without(ComponentId, Box<QueryAccess>),
     Union(Vec<QueryAccess>),
 }
 
 impl QueryAccess {
     pub fn read<T: 'static>() -> QueryAccess {
-        QueryAccess::Read(TypeId::of::<T>(), std::any::type_name::<T>())
+        QueryAccess::Read(TypeId::of::<T>().into(), std::any::type_name::<T>())
     }
 
     pub fn write<T: 'static>() -> QueryAccess {
-        QueryAccess::Write(TypeId::of::<T>(), std::any::type_name::<T>())
+        QueryAccess::Write(TypeId::of::<T>().into(), std::any::type_name::<T>())
     }
 
     pub fn with<T: 'static>(access: QueryAccess) -> QueryAccess {
-        QueryAccess::With(TypeId::of::<T>(), Box::new(access))
+        QueryAccess::With(TypeId::of::<T>().into(), Box::new(access))
     }
 
     pub fn without<T: 'static>(access: QueryAccess) -> QueryAccess {
-        QueryAccess::Without(TypeId::of::<T>(), Box::new(access))
+        QueryAccess::Without(TypeId::of::<T>().into(), Box::new(access))
     }
 
     pub fn optional(access: QueryAccess) -> QueryAccess {
@@ -82,29 +83,29 @@ impl QueryAccess {
         }
     }
 
-    pub fn get_type_name(&self, type_id: TypeId) -> Option<&'static str> {
+    pub fn get_type_name(&self, component_id: ComponentId) -> Option<&'static str> {
         match self {
             QueryAccess::None => None,
-            QueryAccess::Read(current_type_id, name) => {
-                if type_id == *current_type_id {
+            QueryAccess::Read(current_component_id, name) => {
+                if component_id == *current_component_id {
                     Some(*name)
                 } else {
                     None
                 }
             }
-            QueryAccess::Write(current_type_id, name) => {
-                if type_id == *current_type_id {
+            QueryAccess::Write(current_component_id, name) => {
+                if component_id == *current_component_id {
                     Some(*name)
                 } else {
                     None
                 }
             }
-            QueryAccess::Optional(query_access) => query_access.get_type_name(type_id),
-            QueryAccess::With(_, query_access) => query_access.get_type_name(type_id),
-            QueryAccess::Without(_, query_access) => query_access.get_type_name(type_id),
+            QueryAccess::Optional(query_access) => query_access.get_type_name(component_id),
+            QueryAccess::With(_, query_access) => query_access.get_type_name(component_id),
+            QueryAccess::Without(_, query_access) => query_access.get_type_name(component_id),
             QueryAccess::Union(query_accesses) => {
                 for query_access in query_accesses.iter() {
-                    if let Some(name) = query_access.get_type_name(type_id) {
+                    if let Some(name) = query_access.get_type_name(component_id) {
                         return Some(name);
                     }
                 }
@@ -125,19 +126,21 @@ impl QueryAccess {
         match self {
             QueryAccess::None => Some(Access::None),
             QueryAccess::Read(ty, _) => {
-                if archetype.has_type(*ty) {
+                if archetype.has_component(*ty) {
                     if let Some(type_access) = type_access {
-                        type_access.add_read(ArchetypeComponent::new_ty(archetype_index, *ty));
+                        type_access
+                            .add_read(ArchetypeComponent::new_component(archetype_index, *ty));
                     }
                     Some(Access::Read)
                 } else {
                     None
                 }
             }
             QueryAccess::Write(ty, _) => {
-                if archetype.has_type(*ty) {
+                if archetype.has_component(*ty) {
                     if let Some(type_access) = type_access {
-                        type_access.add_write(ArchetypeComponent::new_ty(archetype_index, *ty));
+                        type_access
+                            .add_write(ArchetypeComponent::new_component(archetype_index, *ty));
                     }
                     Some(Access::Write)
                 } else {
@@ -157,14 +160,14 @@ impl QueryAccess {
                 }
             }
             QueryAccess::With(ty, query_access) => {
-                if archetype.has_type(*ty) {
+                if archetype.has_component(*ty) {
                     query_access.get_access(archetype, archetype_index, type_access)
                 } else {
                     None
                 }
             }
             QueryAccess::Without(ty, query_access) => {
-                if !archetype.has_type(*ty) {
+                if !archetype.has_component(*ty) {
                     query_access.get_access(archetype, archetype_index, type_access)
                 } else {
                     None
@@ -308,7 +311,7 @@ mod tests {
         let e3_c = ArchetypeComponent::new::<C>(e3_archetype);
 
         let mut a_type_access = TypeAccess::default();
-        <(&A,) as Query>::Fetch::access()
+        <(&A,) as Query>::Fetch::access(&())
             .get_world_archetype_access(&world, Some(&mut a_type_access));
 
         assert_eq!(
@@ -317,7 +320,7 @@ mod tests {
         );
 
         let mut a_b_type_access = TypeAccess::default();
-        <(&A, &B) as Query>::Fetch::access()
+        <(&A, &B) as Query>::Fetch::access(&())
             .get_world_archetype_access(&world, Some(&mut a_b_type_access));
 
         assert_eq!(
@@ -326,7 +329,7 @@ mod tests {
         );
 
         let mut a_bmut_type_access = TypeAccess::default();
-        <(&A, &mut B) as Query>::Fetch::access()
+        <(&A, &mut B) as Query>::Fetch::access(&())
             .get_world_archetype_access(&world, Some(&mut a_bmut_type_access));
 
         assert_eq!(
@@ -335,7 +338,7 @@ mod tests {
         );
 
         let mut a_option_bmut_type_access = TypeAccess::default();
-        <(Entity, &A, Option<&mut B>) as Query>::Fetch::access()
+        <(Entity, &A, Option<&mut B>) as Query>::Fetch::access(&())
             .get_world_archetype_access(&world, Some(&mut a_option_bmut_type_access));
 
         assert_eq!(
@@ -344,7 +347,7 @@ mod tests {
         );
 
         let mut a_with_b_type_access = TypeAccess::default();
-        <With<B, &A> as Query>::Fetch::access()
+        <With<B, &A> as Query>::Fetch::access(&())
             .get_world_archetype_access(&world, Some(&mut a_with_b_type_access));
 
         assert_eq!(
@@ -353,7 +356,7 @@ mod tests {
         );
 
         let mut a_with_b_option_c_type_access = TypeAccess::default();
-        <With<B, (&A, Option<&mut C>)> as Query>::Fetch::access()
+        <With<B, (&A, Option<&mut C>)> as Query>::Fetch::access(&())
             .get_world_archetype_access(&world, Some(&mut a_with_b_option_c_type_access));
 
         assert_eq!(

crates/bevy_ecs/hecs/src/archetype.rs

@@ -26,7 +26,7 @@ use bevy_utils::AHasher;
 use core::{
     any::TypeId,
     cell::UnsafeCell,
-    hash::{BuildHasherDefault, Hasher},
+    hash::{BuildHasherDefault, Hash, Hasher},
     mem,
     ptr::{self, NonNull},
 };
@@ -243,7 +243,8 @@ impl Archetype {
         size: usize,
         index: usize,
     ) -> Option<NonNull<u8>> {
-        debug_assert!(index < self.len);
+        // TODO(zicklag): I'm pretty sure that it is valid for the index to be zero
+        debug_assert!(index < self.len || index == 0);
         Some(NonNull::new_unchecked(
             (*self.data.get())
                 .as_ptr()
@@ -500,11 +501,14 @@ impl TypeState {
 }
 
 /// Metadata required to store a component
-#[derive(Debug, Copy, Clone)]
+#[derive(Debug, Copy, Clone, Eq, PartialEq)]
 pub struct TypeInfo {
-    id: ComponentId,
-    layout: Layout,
-    drop: unsafe fn(*mut u8),
+    /// The ID unique to the component type
+    pub(crate) id: ComponentId,
+    /// The memory layout of the component
+    pub(crate) layout: Layout,
+    /// The drop function for the component
+    pub(crate) drop: unsafe fn(*mut u8),
 }
 
 impl TypeInfo {
@@ -521,6 +525,16 @@ impl TypeInfo {
         }
     }
 
+    /// Get the [`TypeInfo`] for an external type with the given layout and drop function
+    #[cfg(feature = "dynamic-api")]
+    pub fn of_external(external_id: u64, layout: Layout, drop: unsafe fn(*mut u8)) -> Self {
+        TypeInfo {
+            id: ComponentId::ExternalId(external_id),
+            layout,
+            drop,
+        }
+    }
+
     #[allow(missing_docs)]
     #[inline]
     pub fn id(&self) -> ComponentId {
@@ -538,6 +552,16 @@ impl TypeInfo {
     }
 }
 
+#[allow(clippy::derive_hash_xor_eq)]
+impl Hash for TypeInfo {
+    fn hash<H: Hasher>(&self, state: &mut H) {
+        self.id.hash(state);
+        state.write_usize(self.layout.size());
+        state.write_usize(self.layout.align());
+        self.drop.hash(state);
+    }
+}
+
 impl PartialOrd for TypeInfo {
     fn partial_cmp(&self, other: &Self) -> Option<core::cmp::Ordering> {
         Some(self.cmp(other))
@@ -555,14 +579,6 @@ impl Ord for TypeInfo {
     }
 }
 
-impl PartialEq for TypeInfo {
-    fn eq(&self, other: &Self) -> bool {
-        self.id == other.id
-    }
-}
-
-impl Eq for TypeInfo {}
-
 fn align(x: usize, alignment: usize) -> usize {
     debug_assert!(alignment.is_power_of_two());
     (x + alignment - 1) & (!alignment + 1)