Improve docs, rename to fn_pointers

crates/bevy_ecs/src/reflect.rs

@@ -175,10 +175,21 @@ impl ReflectComponent {
 
     /// The underlying function pointers implementing methods on `ReflectComponent`.
     ///
-    /// Prefer using the methods over fetching the function pointers.
-    /// However, this is useful if you want to cache the functions rather than
-    /// repetitively using `TypeRegistry::get()` followed by `data()`.
-    pub fn fn_pointer(&self) -> &ReflectComponentFns {
+    /// This is useful when you want to keep track locally of an individual
+    /// function pointer.
+    ///
+    /// Calling [`TypeRegistry::get`] followed by
+    /// [`TypeRegistration::data::<ReflectComponent>`] can be costly if done several
+    /// times per frame. Consider cloning [`ReflectComponent`] and keeping it
+    /// between frames, cloning a `ReflectComponent` is very cheap.
+    ///
+    /// If you only need a subset of the methods on `ReflectComponent`,
+    /// use `fn_pointers` to get the underlying [`ReflectComponentFns`]
+    /// and copy the subset of function pointers you care about.
+    ///
+    /// [`TypeRegistration::data::<ReflectComponent>`]: bevy_reflect::TypeRegistration::data
+    /// [`TypeRegistry::get`]: bevy_reflect::TypeRegistry::get
+    pub fn fn_pointers(&self) -> &ReflectComponentFns {
         &self.0
     }
 }
@@ -372,10 +383,21 @@ impl ReflectResource {
 
     /// The underlying function pointers implementing methods on `ReflectResource`.
     ///
-    /// Prefer using the methods over fetching the function pointers.
-    /// However, this is useful if you want to cache the functions rather than
-    /// repetitively using `TypeRegistry::get()` followed by `data()`.
-    pub fn fn_pointer(&self) -> &ReflectResourceFns {
+    /// This is useful when you want to keep track locally of an individual
+    /// function pointer.
+    ///
+    /// Calling [`TypeRegistry::get`] followed by
+    /// [`TypeRegistration::data::<ReflectResource>`] can be costly if done several
+    /// times per frame. Consider cloning [`ReflectResource`] and keeping it
+    /// between frames, cloning a `ReflectResource` is very cheap.
+    ///
+    /// If you only need a subset of the methods on `ReflectResource`,
+    /// use `fn_pointers` to get the underlying [`ReflectResourceFns`]
+    /// and copy the subset of function pointers you care about.
+    ///
+    /// [`TypeRegistration::data::<ReflectResource>`]: bevy_reflect::TypeRegistration::data
+    /// [`TypeRegistry::get`]: bevy_reflect::TypeRegistry::get
+    pub fn fn_pointers(&self) -> &ReflectResourceFns {
         &self.0
     }
 }