From a45f73c7388b3f5a5901bfcc66fd2d1df58d3001 Mon Sep 17 00:00:00 2001
From: sanine <sanine.not@pm.me>
Date: Wed, 22 Mar 2023 10:02:47 -0500
Subject: add update function system

---
 honey/ecs.lua | 68 ++++++++++++++++++++++++++++++++++-------------------------
 1 file changed, 39 insertions(+), 29 deletions(-)

(limited to 'honey')

diff --git a/honey/ecs.lua b/honey/ecs.lua
index 3bdf850..4eee343 100644
--- a/honey/ecs.lua
+++ b/honey/ecs.lua
@@ -98,25 +98,26 @@ function Filter.checkNOR(self, entity)
 end
 
 
---===== worlds =====--
+--===== levels =====--
 
-World = {}
-World.__index = World
+Level = {}
+Level.__index = Level
 
-function World.new(_)
+function Level.new(_)
 	local self = {}
 	self.systems = {}
 	self.entities = {}
-	setmetatable(self, World)
+	self.nextId = 1
+	setmetatable(self, Level)
 	return self
 end
-setmetatable(World, {__call=World.new})
+setmetatable(Level, {__call=Level.new})
 
 
 local function systemLt(a, b)
 	return (a.priority or 50) < (b.priority or 50)
 end
-function World.addSystem(self, system)
+function Level.addSystem(self, system)
 	assert(system.update, "systems must have an 'update' key")
 	assert(system.filter, "systems must have a 'filter' key")
 	system.entities = {}
@@ -125,67 +126,76 @@ function World.addSystem(self, system)
 end
 
 
-local function addEntityToSystem(system, entity)
+local function addEntityToSystem(system, id, entity)
 	-- check if entity is already present
-	if system.entities[entity] then return end
+	if system.entities[id] then return end
 
 	if system.onAddEntity then
-		system.onAddEntity(entity)
+		system.onAddEntity(id, entity)
 	end
-	system.entities[entity] = true
+	system.entities[id] = true
 end
 
 
-local function removeEntityFromSystem(system, entity)
+local function removeEntityFromSystem(system, id, entity)
 	-- check if entity is already absent
-	if not system.entities[entity] then return end
+	if not system.entities[id] then return end
 
 	if system.onRemoveEntity then
-		system.onRemoveEntity(entity)
+		system.onRemoveEntity(id, entity)
 	end
-	system.entities[entity] = nil
+	system.entities[id] = nil
 end
 
 
-function World.addEntity(self, entity)
-	self.entities[entity] = true
+function Level.addEntity(self, entity)
+	table.insert(self.entities, entity)
+	local id = self.nextId
+	self.nextId = id + 1
+
 	for _, system in ipairs(self.systems) do
 		if system.filter(entity) then
-			addEntityToSystem(system, entity)
+			addEntityToSystem(system, id, entity)
 		end
 	end
+
+	return id
 end
 
 
-function World.reconfigureEntity(self, entity)
+function Level.reconfigureEntity(self, id)
+	local entity = self.entities[id]
+	
 	for _, system in ipairs(self.systems) do
 		if system.filter(entity) then
-			addEntityToSystem(system, entity)
+			addEntityToSystem(system, id, entity)
 		else
-			removeEntityFromSystem(system, entity)
+			removeEntityFromSystem(system, id, entity)
 		end
 	end
 end
 
 
-function World.removeEntity(self, entity)
-	self.entities[entity] = nil
+function Level.removeEntity(self, id)
+	local entity = self.entities[id]
 	for _, system in ipairs(self.systems) do
-		removeEntityFromSystem(system, entity)
+		removeEntityFromSystem(system, id, entity)
 	end
+	self.entities[id] = nil
 end
 
 
-function World.reconfigureAllEntities(self)
-	for entity in pairs(self.entities) do
-		self:reconfigureEntity(entity)
+function Level.reconfigureAllEntities(self)
+	for id in ipairs(self.entities) do
+		self:reconfigureEntity(id)
 	end
 end
 
 
-function World.update(self, dt)
+function Level.update(self, dt)
 	for _, system in ipairs(self.systems) do
-		for entity in pairs(system.entities) do
+		for id in pairs(system.entities) do
+			local entity = self.entities[id]
 			system.update(entity, dt)
 		end
 	end
-- 
cgit v1.2.1