Tweaked: Archetypes keep their index in the list for fast lookup duri…

…ng removals

Tweaked: Cleanup of core component registration

include/gaia/ecs/archetype.h

@@ -125,6 +125,9 @@ namespace gaia {
 			//! Number of ticks before empty chunks are removed
 			static constexpr uint16_t MAX_ARCHETYPE_LIFESPAN = (1 << ARCHETYPE_LIFESPAN_BITS) - 1;
 
+			//! Archetype list index
+			uint32_t m_listIdx;
+
 			//! Delete requested
 			uint32_t m_deleteReq : 1;
 			//! Remaining lifespan of the archetype
@@ -138,7 +141,7 @@ namespace gaia {
 
 			//! Constructor is hidden. Create archetypes via Archetype::Create
 			Archetype(const ComponentCache& cc, uint32_t& worldVersion):
-					m_cc(cc), m_worldVersion(worldVersion),
+					m_cc(cc), m_worldVersion(worldVersion), m_listIdx(BadIndex),
 					//
 					m_deleteReq(0), m_lifespanCountdown(0), m_dead(0), m_pairCnt(0), m_pairCnt_is(0) {}
 
@@ -260,6 +263,14 @@ namespace gaia {
 					Chunk::free(pChunk);
 			}
 
+			void list_idx(uint32_t idx) {
+				m_listIdx = idx;
+			}
+
+			uint32_t list_idx() const {
+				return m_listIdx;
+			}
+
 			GAIA_NODISCARD bool cmp_comps(const ArchetypeLookupChecker& other) const {
 				return ecs::cmp_comps({m_ids.data(), m_ids.size()}, other.m_comps);
 			}

include/gaia/ecs/id.h

@@ -450,7 +450,7 @@ namespace gaia {
 		struct Acyclic_ {};
 		struct All_ {};
 		struct ChildOf_ {};
-		struct AliasOf_ {};
+		struct Is_ {};
 
 		//----------------------------------------------------------------------
 		// Core component entities
@@ -473,7 +473,8 @@ namespace gaia {
 		inline Entity Acyclic = Entity(10, false, false, false, EntityKind::EK_Gen);
 		//! Wildcard query entity
 		inline Entity All = Entity(11, 0, false, false, EntityKind::EK_Gen);
-		//! Entity representing a physical hierarchy
+		//! Entity representing a physical hierarchy.
+		//! When the relationship target is deleted all children are deleted as well.
 		inline Entity ChildOf = Entity(12, 0, false, false, EntityKind::EK_Gen);
 		//! Alias for a base entity
 		inline Entity Is = Entity(13, 0, false, false, EntityKind::EK_Gen);