Improve docs more, to_identifier helper method

Author: Bluefinger

crates/bevy_ecs/src/entity/mod.rs

@@ -267,7 +267,13 @@ impl Entity {
     /// No particular structure is guaranteed for the returned bits.
     #[inline(always)]
     pub const fn to_bits(self) -> u64 {
-        Identifier::from_parts(self.index, self.generation).to_bits()
+        self.to_identifier().to_bits()
+    }
+
+    /// Convert to an [`Identifier`].
+    #[inline(always)]
+    pub const fn to_identifier(self) -> Identifier {
+        Identifier::from_parts(self.index, self.generation)
     }
 
     /// Reconstruct an `Entity` previously destructured with [`Entity::to_bits`].
@@ -329,7 +335,7 @@ impl Entity {
     /// given index has been reused (index, generation) pairs uniquely identify a given Entity.
     #[inline]
     pub const fn generation(self) -> u32 {
-        Identifier::from_parts(self.index, self.generation).masked_high()
+        self.to_identifier().masked_high()
     }
 }
 
@@ -350,7 +356,7 @@ impl From<Entity> for Identifier {
         // Entity's layout is exactly the same as Identifier, therefore
         // this will remove any panic! path as we know Entity -> Identifier
         // conversions will never panic.
-        Identifier::from_parts(value.index, value.generation)
+        value.to_identifier()
     }
 }
 

crates/bevy_ecs/src/identifier/mod.rs

@@ -15,8 +15,7 @@ pub(crate) mod masks;
 
 /// A unified identifier for all entity and similar IDs.
 /// Has the same size as a `u64` integer, but the layout is split between a 32-bit low
-/// segment, a 31-bit high segment, and the significant bit reserved as type flags to denote
-/// entity kinds.
+/// segment, a 30-bit high segment, and the 2 most significant bits reserved as bit flags.
 #[derive(Debug, Clone, Copy)]
 // Alignment repr necessary to allow LLVM to better output
 // optimised codegen for `to_bits`, `PartialEq` and `Ord`.
@@ -32,8 +31,8 @@ pub struct Identifier {
 }
 
 impl Identifier {
-    /// Construct a new [`Identifier`]. The `high` parameter is masked with the
-    /// `kind` so to pack the high value and bit flags into the same field.
+    /// Construct a new [`Identifier`]. The `high` parameter is masked so to pack
+    /// the high value and bit flags into the same field.
     #[inline(always)]
     pub const fn new(
         low: u32,
@@ -56,10 +55,10 @@ impl Identifier {
             // SAFETY: The high value has been checked to ensure it is never
             // zero.
             unsafe {
-                Ok(Self {
+                Ok(Self::from_parts(
                     low,
-                    high: NonZeroU32::new_unchecked(packed_high),
-                })
+                    NonZeroU32::new_unchecked(packed_high),
+                ))
             }
         }
     }