Added: Deleting queries from query cache

Changed: TListItem::create -> handle
Changed: core::erase_fast -> swap_erase

README.md

@@ -589,6 +589,29 @@ q.add({p, QueryOpKind::All, QueryAccess::Write})
  .add({pl, QueryOpKind::None, QueryAccess::None}); 
 ```
 
+Building cache requires memory. Because of that, sometimes it comes handy having the ability to release this data. Calling ```myQuery.reset()``` will remove any data allocated by the query. The next time the query is used to fetch results the cache is rebuilt.
+
+```cpp
+q.reset();
+```
+
+If this is a cached query, even after resetting it it still remains in the query cache. To remove it from there all queries with the matching signature will need to be destroyed first:
+
+```cpp
+ecs::Query q1 = w.query();
+ecs::Query q2 = w.query();
+q1.add<Position>();
+q2.add<Position>();
+
+(void)q1.count(); // do some operation that compiles the query and inserts it into the query cache
+(void)q2.count(); // do some operation that compiles the query and inserts it into the query cache
+
+q1 = w.query(); // First reference to cached query is destroyed.
+q2 = w.query(); // Last reference to cache query is destroyed. The cache is cleared of queries with the given signature
+```
+
+Technically, any query could be reset by default initializing it, e.g. ```myQuery = {}```. This, however, puts the query into an invalid state. Only queries created via World::query have a valid state.
+
 ### Query string
 Another way to define queries is using the string notation. This allows you to define the entire query or its parts using a string composed of simple expressions. Any spaces in between modifiers and expressions are trimmed.
 

gaia.code-workspace

@@ -177,5 +177,6 @@
 			"upci",
 			"upos"
 		],
+		"makefile.configureOnOpen": false,
 	}
 }

include/gaia/cnt/ilist.h

@@ -102,6 +102,10 @@ namespace gaia {
 				return {(pointer)m_items.data() + size()};
 			}
 
+			void reserve(size_type cap) {
+				m_items.reserve(cap);
+			}
+
 			//! Allocates a new item in the list
 			//! \return Handle to the new item
 			GAIA_NODISCARD TItemHandle alloc(void* ctx) {
@@ -115,7 +119,7 @@ namespace gaia {
 					GAIA_GCC_WARNING_DISABLE("-Wmissing-field-initializers");
 					GAIA_CLANG_WARNING_DISABLE("-Wmissing-field-initializers");
 					m_items.push_back(TListItem::create(itemCnt, 0U, ctx));
-					return TListItem::create(m_items.back());
+					return TListItem::handle(m_items.back());
 					GAIA_GCC_WARNING_POP()
 					GAIA_CLANG_WARNING_POP()
 				}
@@ -128,7 +132,7 @@ namespace gaia {
 				auto& j = m_items[m_nextFreeIdx];
 				m_nextFreeIdx = j.idx;
 				j = TListItem::create(index, j.gen, ctx);
-				return TListItem::create(j);
+				return TListItem::handle(j);
 			}
 
 			//! Allocates a new item in the list

include/gaia/ecs/archetype.h

@@ -33,10 +33,8 @@ namespace gaia {
 		namespace detail {
 			GAIA_NODISCARD inline bool cmp_comps(EntitySpan comps, EntitySpan compsOther) {
 				// Size has to match
-				GAIA_FOR(EntityKind::EK_Count) {
-					if (comps.size() != compsOther.size())
+				if (comps.size() != compsOther.size())
 						return false;
-				}
 
 				// Elements have to match
 				GAIA_EACH(comps) {
@@ -467,7 +465,7 @@ namespace gaia {
 				// with the last one in the array. Therefore, we first update the last item's
 				// index with the current chunk's index and then do the swapping.
 				m_chunks.back()->set_idx(chunkIndex);
-				core::erase_fast(m_chunks, chunkIndex);
+				core::swap_erase(m_chunks, chunkIndex);
 
 				// Delete the chunk now. Otherwise, if the chunk happened to be the last
 				// one we would end up overriding released memory.

include/gaia/ecs/chunk.h

@@ -1139,23 +1139,23 @@ namespace gaia {
 				return m_header.lifespanCountdown > 0;
 			}
 
-			//! Marks the chunk as dead
+			//! Marks the chunk as dead (ready to delete)
 			void die() {
 				m_header.dead = 1;
 			}
 
-			//! Checks is this chunk is dying
+			//! Checks is this chunk is dead (ready to delete)
 			GAIA_NODISCARD bool dead() const {
 				return m_header.dead == 1;
 			}
 
-			//! Starts the process of dying
+			//! Starts the process of dying (not yet ready to delete, can be revived)
 			void start_dying() {
 				GAIA_ASSERT(!dead());
 				m_header.lifespanCountdown = ChunkHeader::MAX_CHUNK_LIFESPAN;
 			}
 
-			//! Makes the chunk alive again
+			//! Makes a dying chunk alive again
 			void revive() {
 				GAIA_ASSERT(!dead());
 				m_header.lifespanCountdown = 0;

include/gaia/ecs/chunk_allocator.h

@@ -256,7 +256,7 @@ namespace gaia {
 					if (pPage->full()) {
 						// Remove the page from the open list and update the swapped page's pointer
 						container.pagesFree.back()->m_idx = 0;
-						core::erase_fast(container.pagesFree, 0);
+						core::swap_erase(container.pagesFree, 0);
 
 						// Move our page to the full list
 						pPage->m_idx = (uint32_t)container.pagesFull.size();
@@ -301,7 +301,7 @@ namespace gaia {
 					if (wasFull) {
 						// Our page is no longer full. Remove it from the full list and update the swapped page's pointer
 						container.pagesFull.back()->m_idx = pPage->m_idx;
-						core::erase_fast(container.pagesFull, pPage->m_idx);
+						core::swap_erase(container.pagesFull, pPage->m_idx);
 
 						// Move our page to the open list
 						pPage->m_idx = (uint32_t)container.pagesFree.size();
@@ -314,7 +314,7 @@ namespace gaia {
 						if (pPage->empty()) {
 							GAIA_ASSERT(!container.pagesFree.empty());
 							container.pagesFree.back()->m_idx = pPage->m_idx;
-							core::erase_fast(container.pagesFree, pPage->m_idx);
+							core::swap_erase(container.pagesFree, pPage->m_idx);
 						}
 
 						try_delete_this();
@@ -345,7 +345,7 @@ namespace gaia {
 
 							GAIA_ASSERT(pPage->m_idx == i);
 							container.pagesFree.back()->m_idx = i;
-							core::erase_fast(container.pagesFree, i);
+							core::swap_erase(container.pagesFree, i);
 							free_page(pPage);
 						}
 					};

include/gaia/ecs/entity_container.h

@@ -73,7 +73,7 @@ namespace gaia {
 
 			EntityContainer() = default;
 
-			static EntityContainer create(uint32_t index, uint32_t generation, void* pCtx) {
+			GAIA_NODISCARD static EntityContainer create(uint32_t index, uint32_t generation, void* pCtx) {
 				auto* ctx = (EntityContainerCtx*)pCtx;
 
 				EntityContainer ec{};
@@ -85,7 +85,7 @@ namespace gaia {
 				return ec;
 			}
 
-			static Entity create(const EntityContainer& ec) {
+			GAIA_NODISCARD static Entity handle(const EntityContainer& ec) {
 				return Entity(ec.idx, ec.gen, (bool)ec.ent, (bool)ec.pair, (EntityKind)ec.kind);
 			}