perf(ecs): remove clearing archetype lookup table

1 files changed, 18 insertions, 20 deletions

diff --git a/ecs/src/component/storage.rs b/ecs/src/component/storage.rs
index b227337..e909395 100644
--- a/ecs/src/component/storage.rs
+++ b/ecs/src/component/storage.rs
@@ -123,41 +123,39 @@ impl Storage
 
     pub fn make_archetype_lookup_entries(&mut self)
     {
-        // TODO: Re-doing the whole archetype lookup table is dumb and slow. Only re-do
-        // the archetype lookup entries that need to be changed
-        self.archetype_lookup.clear();
-
         for pending_entry in self.pending_archetype_lookup_entries.drain(..) {
-            let ids = pending_entry.iter().filter_map(|component_metadata| {
-                if component_metadata.is_optional == ComponentIsOptional::Yes {
-                    return None;
-                }
-
-                Some(component_metadata.id)
-            });
+            let pending_entry_ids_set = pending_entry
+                .iter()
+                .filter_map(|component_metadata| {
+                    if component_metadata.is_optional == ComponentIsOptional::Yes {
+                        return None;
+                    }
 
-            let ids_set: HashSet<_> = ids.collect();
+                    Some(component_metadata.id)
+                })
+                .collect::<HashSet<_>>();
 
             let matching_archetype_indices = self
                 .archetypes
                 .iter()
                 .enumerate()
                 .filter_map(|(index, archetype)| {
-                    if archetype.component_ids_is_superset(&ids_set) {
+                    if archetype.component_ids_is_superset(&pending_entry_ids_set) {
                         return Some(index);
                     }
 
                     None
                 });
 
-            let archetype_indices = self
-                .archetype_lookup
-                .entry(ArchetypeId::from_components_metadata(
-                    pending_entry.into_iter(),
-                ))
-                .or_default();
+            let archetype_id =
+                ArchetypeId::from_components_metadata(pending_entry.into_iter());
 
-            archetype_indices.extend(matching_archetype_indices);
+            if self.archetype_lookup.contains_key(&archetype_id) {
+                continue;
+            }
+
+            self.archetype_lookup
+                .insert(archetype_id, matching_archetype_indices.collect());
         }
     }
 }