Polishing

fluid/component.lua

@@ -21,7 +21,7 @@ end
 -- Creates and initializes a new Bag.
 -- @param ... The values passed to the populate function
 -- @return A new initialized Bag
-function Component:initialize(...)
+function Component:__initialize(...)
    if self.__populate then
       local bag = {}
       self.__populate(bag, ...)

fluid/entity.lua

@@ -1,22 +1,14 @@
-local Entity = {
-   entities = {},
-}
+local Entity = {}
 Entity.__index = Entity
 
 --- Creates and initializes a new Entity.
 -- @return A new Entity
 function Entity.new()
    local e = setmetatable({
-      id         = #Entity.entities + 1,
       components = {},
-      systems    = {},
-      keys       = {},
-
-      instance = nil,
+      instance   = nil,
    }, Entity)
 
-   Entity.entities[e.id] = e
-
    return e
 end
 
@@ -25,7 +17,7 @@ end
 -- @param ... The values passed to the Component
 -- @return self
 function Entity:give(component, ...)
-   self.components[component] = component:initialize(...)
+   self.components[component] = component:__initialize(...)
 
    return self
 end
@@ -47,15 +39,6 @@ function Entity:check()
    return self
 end
 
---- Removed an Entity from the instance.
--- @return self
-function Entity:destroy()
-   Entity.entities[self.id] = nil
-   self.instance:destroyEntity(self)
-
-   return self
-end
-
 --- Gets a Component from the Entity
 -- @param component The Component to get
 -- @return The Bag from the Component

fluid/eventManager.lua

@@ -3,20 +3,12 @@ EventManager.__index = EventManager
 
 function EventManager.new()
    local eventManager = setmetatable({
-      queue     = {count = 0},
       listeners = {},
    }, EventManager)
 
    return eventManager
 end
 
-function EventManager:push(event)
-   queue.count = queue.count + 1
-   queue[queue.count] = event
-
-   return self
-end
-
 function EventManager:emit(name, ...)
    local listeners = self.listeners[name]
 
@@ -61,19 +53,6 @@ function EventManager:deregister(name, listener)
    return self
 end
 
-function EventManager:process()
-   local queue = self.queue
-
-   for i = 1, queue.count do
-      self:emit(queue[i])
-      queue[i] = nil
-   end
-
-   queue.count = 0
-
-   return self
-end
-
 return setmetatable(EventManager, {
    __call = function(_, ...) return EventManager.new(...) end,
 })

fluid/instance.lua

@@ -1,6 +1,6 @@
 local PATH = (...):gsub('%.[^%.]+$', '')
 
-local Pool         = require(PATH..".pool")
+local List         = require(PATH..".list")
 local EventManager = require(PATH..".eventManager")
 
 local Instance = {}
@@ -8,7 +8,7 @@ Instance.__index = Instance
 
 function Instance.new()
    local instance = setmetatable({
-      entities     = Pool(),
+      entities     = List(),
       eventManager = EventManager(),
 
       systems      = {},
@@ -26,16 +26,14 @@ end
 
 function Instance:checkEntity(e)
    for _, system in ipairs(self.systems) do
-      if system:entityUpdated(e) then
-         e.systems[#e.systems + 1] = system
-      end
+      system:checkEntity(e)
    end
 end
 
-function Instance:destroyEntity(e)
+function Instance:removeEntity(e)
    self.entities:remove(e)
 
-   for _, system in ipairs(e.systems) do
+   for _, system in ipairs(self.systems) do
       system:remove(e)
    end
 end
@@ -69,18 +67,6 @@ function Instance:emit(...)
    return self
 end
 
-function Instance:update(dt)
-   self:emit("update", dt)
-
-   return self
-end
-
-function Instance:draw()
-   self:emit("draw")
-
-   return self
-end
-
 return setmetatable(Instance, {
    __call = function(_, ...) return Instance.new(...) end,
 })

fluid/list.lua

@@ -34,18 +34,17 @@ function List:remove(obj)
 
       self.numerical[index] = other
       self.named[other]     = index
+
+      self.numerical[size] = nil
    end
 
+
    self.named[obj] = nil
    self.size = size - 1
 end
 
-function List:get(i)
-   return self.numerical[i]
-end
-
-function List:getIndex(obj)
-   return self.named[obj]
+function List:has(obj)
+   return self.named[obj] and true
 end
 
 return setmetatable(List, {

fluid/pool.lua

@@ -1,17 +1,21 @@
+local PATH = (...):gsub('%.[^%.]+$', '')
+
+local List = require(PATH..".list")
+
 local Pool = {}
 Pool.__index = Pool
 
 function Pool.new(name, filter)
-   local pool = setmetatable({
-      __filter = filter,
-      __name   = name,
-   }, Pool)
+   local pool = setmetatable(List(), Pool)
 
+   pool.name   = name
+   pool.filter = filter
+   
    return pool
 end
 
 function Pool:eligible(e)
-   for _, component in ipairs(self.__filter) do
+   for _, component in ipairs(self.filter) do
       if not e.components[component] then
          return false
       end
@@ -20,38 +24,7 @@ function Pool:eligible(e)
    return true
 end
 
-function Pool:add(e)
-   local key = #self + 1
-
-   self[key] = e
-   e.keys[self] = key
-end
-
-function Pool:has(e)
-   return e.keys[self] and true
-end
-
-function Pool:remove(e, pool)
-   local key = e.keys[self]
-
-   if key then
-      local count = #self
-
-      if key == count then
-         self[key]    = nil
-         e.keys[self] = nil
-      else
-         local swap = self[count]
-
-         self[key]       = swap
-         self[count]     = nil
-         swap.keys[self] = key
-      end
-
-      return true
-   end
-end
-
 return setmetatable(Pool, {
-   __call = function(_, ...) return Pool.new(...) end,
+   __index = List,
+   __call  = function(_, ...) return Pool.new(...) end,
 })

fluid/system.lua

@@ -14,11 +14,11 @@ function System.new(...)
 
    for _, filter in pairs({...}) do
       local pool = system:buildPool(filter)
-      if not system[pool.__name] then
-         system[pool.__name]                 = pool
+      if not system[pool.name] then
+         system[pool.name]                 = pool
          system.__pools[#system.__pools + 1] = pool
       else
-         error("Pool with name '"..pool.__name.."' already exists.")
+         error("Pool with name '"..pool.name.."' already exists.")
       end
    end
 
@@ -40,7 +40,7 @@ function System:buildPool(pool)
    return Pool(name, filter)
 end
 
-function System:entityUpdated(e)
+function System:checkEntity(e)
    local systemHas = self:has(e)
 
    for _, pool in ipairs(self.__pools) do

main.lua

@@ -0,0 +1,107 @@
+local Fluid = require("fluid").init({
+   useEvents = true
+})
+local Entity    = Fluid.entity
+local Component = Fluid.component
+local System    = Fluid.system
+
+local Game = Fluid.instance()
+Fluid.addInstance(Game)
+
+local Position = Component(function(e, x, y)
+   e.x = x
+   e.y = y
+end)
+
+local Rectangle = Component(function(e, w, h)
+   e.w = w
+   e.h = h
+end)
+
+local Circle = Component(function(e, r)
+   e.r = r
+end)
+
+local Color = Component(function(e, r, g, b, a)
+   e.r = r
+   e.g = g
+   e.b = b
+   e.a = a
+end)
+
+local RectangleRenderer = System({Position, Rectangle})
+function RectangleRenderer:draw()
+   for _, e in ipairs(self.pool.numerical) do
+      local position  = e:get(Position)
+      local rectangle = e:get(Rectangle)
+      local color     = e:get(Color)
+
+      love.graphics.setColor(255, 255, 255)
+      if color then
+         love.graphics.setColor(color.r, color.g, color.b, color.a)
+      end
+
+      love.graphics.rectangle("fill", position.x, position.y, rectangle.w, rectangle.h)
+   end
+end
+
+local CircleRenderer = System({Position, Circle})
+function CircleRenderer:draw()
+   for _, e in ipairs(self.pool.numerical) do
+      local position = e:get(Position)
+      local circle   = e:get(Circle)
+      local color    = e:get(Color)
+
+      love.graphics.setColor(255, 255, 255)
+      if color then
+         love.graphics.setColor(color.r, color.g, color.b, color.a)
+      end
+
+      love.graphics.circle("fill", position.x, position.y, circle.r)
+   end
+end
+
+local RandomRemover = System({})
+RandomRemover.time = 0
+
+function RandomRemover:update(dt)
+   RandomRemover.time = RandomRemover.time + dt
+
+   if RandomRemover.time >= 0.125 then
+      RandomRemover.time = 0
+
+      if self.pool.size > 0 then
+         local i = love.math.random(1, self.pool.size)
+
+         Game:removeEntity(self.pool.numerical[i])
+      end
+   end
+end
+
+Game:addSystem(RandomRemover, "update")
+Game:addSystem(RectangleRenderer, "draw")
+Game:addSystem(CircleRenderer, "draw")
+
+for i = 1, 50 do
+   local e = Entity()
+   e:give(Position, love.math.random(0, 700), love.math.random(0, 700))
+   e:give(Rectangle, love.math.random(5, 20), love.math.random(5, 20))
+
+   if love.math.random(0, 1) == 0 then
+      e:give(Color, love.math.random(0, 255), love.math.random(0, 255), love.math.random(0, 255), 255)
+   end
+
+   Game:addEntity(e)
+end
+
+for i = 1, 50 do
+   local e = Entity()
+   e:give(Position, love.math.random(0, 700), love.math.random(0, 700))
+   e:give(Circle, love.math.random(5, 20))
+
+   if love.math.random(0, 1) == 0 then
+      e:give(Color, love.math.random(0, 255), love.math.random(0, 255), love.math.random(0, 255), 255)
+   end
+
+   Game:addEntity(e)
+end