Optimize moving archetype

jecs.luau

@@ -439,6 +439,7 @@ end
 
 local function archetype_move(
 	entity_index: EntityIndex,
+	entity: Entity,
 	to: Archetype,
 	dst_row: i24,
 	from: Archetype,
@@ -452,6 +453,9 @@ local function archetype_move(
 	local id_types = from.types
 	local columns_map = to.columns_map
 
+	if src_row ~= last then
+		-- If the entity is the last row in the archetype then swapping it would be meaningless.
+
 		for i, column in src_columns do
 			if column == NULL_ARRAY then
 				continue
@@ -465,35 +469,42 @@ local function archetype_move(
 				dst_column[dst_row] = column[src_row]
 			end
 
-		-- If the entity is the last row in the archetype then swapping it would be meaningless.
-		if src_row ~= last then
 			-- Swap rempves columns to ensure there are no holes in the archetype.
 			column[src_row] = column[last]
-		end
 			column[last] = nil
 		end
 
-	local moved = #src_entities
 
 		-- Move the entity from the source to the destination archetype.
 		-- Because we have swapped columns we now have to update the records
 		-- corresponding to the entities' rows that were swapped.
-	local e1 = src_entities[src_row]
-	local e2 = src_entities[moved]
 
-	if src_row ~= moved then
+		local e2 = src_entities[last]
 		src_entities[src_row] = e2
-	end
-
-	src_entities[moved] = nil :: any
-	dst_entities[dst_row] = e1
 
 		local sparse_array = entity_index.sparse_array
-
-	local record1 = sparse_array[ECS_ENTITY_T_LO(e1 :: number)]
 		local record2 = sparse_array[ECS_ENTITY_T_LO(e2 :: number)]
-	record1.row = dst_row
 		record2.row = src_row
+	else
+		for i, column in src_columns do
+			if column == NULL_ARRAY then
+				continue
+			end
+			-- Retrieves the new column index from the source archetype's record from each component
+			-- We have to do this because the columns are tightly packed and indexes may not correspond to each other.
+			local dst_column = columns_map[id_types[i]]
+
+			-- Sometimes target column may not exist, e.g. when you remove a component.
+			if dst_column then
+				dst_column[dst_row] = column[src_row]
+			end
+
+			column[last] = nil
+		end
+	end
+
+	src_entities[last] = nil :: any
+	dst_entities[dst_row] = entity
 end
 
 local function archetype_append(
@@ -526,7 +537,7 @@ local function entity_move(
 	local sourceRow = record.row
 	local from = record.archetype
 	local dst_row = archetype_append(entity, to)
-	archetype_move(entity_index, to, dst_row, from, sourceRow)
+	archetype_move(entity_index, entity, to, dst_row, from, sourceRow)
 	record.archetype = to
 	record.row = dst_row
 end
@@ -2459,8 +2470,8 @@ local function world_new()
 				local idr_archetype = archetypes[archetype_id]
 				local entities = idr_archetype.entities
 				local n = #entities
+				table.move(entities, 1, n, count + 1, queue)
 				count += n
-				table.move(entities, 1, n, #queue + 1, queue)
 			end
 			for _, e in queue do
 				inner_world_remove(world, e, entity)

test/tests.luau

@@ -22,57 +22,10 @@ type Entity<T=nil> = jecs.Entity<T>
 type Id<T=unknown> = jecs.Id<T>
 
 local entity_visualiser = require("@tools/entity_visualiser")
-local lifetime_tracker_add = require("@tools/lifetime_tracker")
 local dwi = entity_visualiser.stringify
 
-TEST("repro#", function()
+TEST("repro", function()
-	do CASE "pair(OnDelete, Delete)"
-	    local world = jecs.world()
-	    local ct = world:component()
-	    world:add(ct, jecs.pair(jecs.OnDelete, jecs.Delete))
 
-	    local e1 = world:entity()
-	    local e2 = world:entity()
-
-	    local dummy = world:entity()
-
-	    world:add(e1, ct)
-	    world:add(e2, jecs.pair(ct, dummy))
-
-	    world:delete(dummy)
-
-	    CHECK(world:contains(e2))
-
-	    world:delete(ct)
-
-	    CHECK(not world:contains(e1))
-	end
-
-	do CASE "pair(OnDeleteTarget, Delete)"
-		print("start")
-	    local world = jecs.world()
-	    local ct = world:component()
-	    world:add(ct, jecs.pair(jecs.OnDeleteTarget, jecs.Delete))
-
-	    local e1 = world:entity()
-	    local e2 = world:entity()
-
-	    -- local dummy = world:entity()
-
-		print("flags")
-	    world:add(e1, ct)
-
-		print(world.component_index[ct].flags)
-	    -- world:add(e2, jecs.pair(ct, dummy))
-
-	    -- world:delete(dummy)
-
-	    -- CHECK(not world:contains(e2))
-
-	    world:delete(ct)
-
-	    CHECK(world:contains(e1))
-	end
 
 end)
 
@@ -433,8 +386,51 @@ TEST("world:contains()", function()
 end)
 
 TEST("world:delete()", function()
+	do CASE "pair(OnDelete, Delete)"
+	    local world = jecs.world()
+	    local ct = world:component()
+	    world:add(ct, jecs.pair(jecs.OnDelete, jecs.Delete))
+
+	    local e1 = world:entity()
+	    local e2 = world:entity()
+
+	    local dummy = world:entity()
+
+	    world:add(e1, ct)
+	    world:add(e2, jecs.pair(ct, dummy))
+
+	    world:delete(dummy)
+
+	    CHECK(world:contains(e2))
+
+	    world:delete(ct)
+
+	    CHECK(not world:contains(e1))
+	end
+
+	do CASE "pair(OnDeleteTarget, Delete)"
+	    local world = jecs.world()
+	    local ct = world:component()
+	    world:add(ct, jecs.pair(jecs.OnDeleteTarget, jecs.Delete))
+
+	    local e1 = world:entity()
+	    local e2 = world:entity()
+
+	    local dummy = world:entity()
+
+	    world:add(e1, ct)
+
+	    world:add(e2, jecs.pair(ct, dummy))
+
+	    world:delete(dummy)
+
+	    CHECK(not world:contains(e2))
+
+	    world:delete(ct)
+
+	    CHECK(world:contains(e1))
+	end
 	do CASE "remove (*, R) pairs when relationship is invalidated"
-		print("-------")
 		local world = jecs.world()
 		local e1 = world:entity()
 		local e2 = world:entity()