Changed EntityManager to dense vector

This should improve speed, because entity lookup will be O(1) instead of O(log n). Deletion is also O(1). Insert stays at potentially O(n), but still should be overall faster than the previous method.

Also replaced some asserts with exceptions.

Also made Component polymorphic so that deletion actually works properly.

1 files changed, 6 insertions, 5 deletions

@@ -4,17 +4,18 @@
 #include "entity_manager.h"
 
 template <>
-std::set<int> EntityManager::getEntitiesWithComponents<>(std::set<std::type_index>& componentTypes)
+std::set<EntityManager::id_type> EntityManager::getEntitiesWithComponents<>(
+  std::set<std::type_index>& componentTypes)
 {
   if (cachedComponents.count(componentTypes) == 1)
   {
     return cachedComponents[componentTypes];
   }
 
-  std::set<int>& cache = cachedComponents[componentTypes];
-  for (auto& entity : entities)
+  std::set<id_type>& cache = cachedComponents[componentTypes];
+  for (id_type entity = 0; entity < entities.size(); entity++)
   {
-    EntityData& data = entity.second;
+    EntityData& data = entities[entity];
     bool cacheEntity = true;
 
     for (auto& componentType : componentTypes)
@@ -28,7 +29,7 @@ std::set<int> EntityManager::getEntitiesWithComponents<>(std::set<std::type_inde
 
     if (cacheEntity)
     {
-      cache.insert(entity.first);
+      cache.insert(entity);
     }
   }