move FloatOrd to bevy_core

crates/bevy_app/src/schedule_plan.rs

@@ -2,7 +2,6 @@ use crate::System;
 use legion::prelude::Schedule;
 use std::{
     borrow::Cow,
-    cmp::Ordering,
     collections::{HashMap, HashSet},
 };
 
@@ -106,33 +105,3 @@ impl SchedulePlan {
         self
     }
 }
-
-// working around the famous "rust float ordering" problem
-#[derive(PartialOrd)]
-struct FloatOrd(f32);
-
-impl Ord for FloatOrd {
-    fn cmp(&self, other: &Self) -> Ordering {
-        self.0.partial_cmp(&other.0).unwrap_or_else(|| {
-            if self.0.is_nan() && !other.0.is_nan() {
-                Ordering::Less
-            } else if !self.0.is_nan() && other.0.is_nan() {
-                Ordering::Greater
-            } else {
-                Ordering::Equal
-            }
-        })
-    }
-}
-
-impl PartialEq for FloatOrd {
-    fn eq(&self, other: &Self) -> bool {
-        if self.0.is_nan() && other.0.is_nan() {
-            true
-        } else {
-            self.0 == other.0
-        }
-    }
-}
-
-impl Eq for FloatOrd {}

crates/bevy_core/src/float_ord.rs

@@ -0,0 +1,41 @@
+use crate::bytes::AsBytes;
+use std::{
+    cmp::Ordering,
+    hash::{Hash, Hasher},
+};
+
+// working around the famous "rust float ordering" problem
+#[derive(Debug, Copy, Clone, PartialOrd)]
+pub struct FloatOrd(pub f32);
+
+impl Ord for FloatOrd {
+    fn cmp(&self, other: &Self) -> Ordering {
+        self.0.partial_cmp(&other.0).unwrap_or_else(|| {
+            if self.0.is_nan() && !other.0.is_nan() {
+                Ordering::Less
+            } else if !self.0.is_nan() && other.0.is_nan() {
+                Ordering::Greater
+            } else {
+                Ordering::Equal
+            }
+        })
+    }
+}
+
+impl PartialEq for FloatOrd {
+    fn eq(&self, other: &Self) -> bool {
+        if self.0.is_nan() && other.0.is_nan() {
+            true
+        } else {
+            self.0 == other.0
+        }
+    }
+}
+
+impl Eq for FloatOrd {}
+
+impl Hash for FloatOrd {
+    fn hash<H: Hasher>(&self, state: &mut H) {
+        state.write(self.0.as_bytes());
+    }
+}

crates/bevy_core/src/lib.rs

@@ -1,6 +1,7 @@
 pub mod bytes;
 pub mod time;
 pub mod transform;
+pub mod float_ord;
 
 use bevy_app::{stage, AppBuilder, AppPlugin};
 use bevy_transform::{