From d4297af78e2a8d8bfa89e922b8b124eccee843fc Mon Sep 17 00:00:00 2001
From: Justin van der Leij <justinvanderleij@gmail.com>
Date: Tue, 30 Jan 2018 12:59:56 +0100
Subject: [PATCH] A bit more polish

---
 fluid/instance.lua |  4 ++--
 fluid/list.lua     | 38 +++++++++++++++++++++-----------------
 fluid/system.lua   | 26 +++++++++++++-------------
 main.lua           | 10 +++++++---
 4 files changed, 43 insertions(+), 35 deletions(-)

diff --git a/fluid/instance.lua b/fluid/instance.lua
index f90ef49..dd6f42e 100644
--- a/fluid/instance.lua
+++ b/fluid/instance.lua
@@ -26,7 +26,7 @@ end
 
 function Instance:checkEntity(e)
    for _, system in ipairs(self.systems) do
-      system:checkEntity(e)
+      system:__checkEntity(e)
    end
 end
 
@@ -34,7 +34,7 @@ function Instance:removeEntity(e)
    self.entities:remove(e)
 
    for _, system in ipairs(self.systems) do
-      system:remove(e)
+      system:__remove(e)
    end
 end
 
diff --git a/fluid/list.lua b/fluid/list.lua
index af67bf5..72fa68e 100644
--- a/fluid/list.lua
+++ b/fluid/list.lua
@@ -3,48 +3,52 @@ local mt = {__index = List}
 
 function List.new()
    return setmetatable({
-      numerical = {},
-      named     = {},
-      size      = 0,
+      objects  = {},
+      pointers = {},
+      size     = 0,
    }, mt)
 end
 
 function List:clear()
-   self.numerical = {}
-   self.named     = {}
-   self.size      = 0
+   self.objects  = {}
+   self.pointers = {}
+   self.size     = 0
 end
 
 function List:add(obj)
    local size = self.size + 1
 
-   self.numerical[size] = obj
-   self.named[obj]      = size
-   self.size            = size
+   self.objects[size] = obj
+   self.pointers[obj] = size
+   self.size          = size
 end
 
 function List:remove(obj)
-   local index = self.named[obj]
+   local index = self.pointers[obj]
    local size  = self.size
 
    if index == size then
-      self.numerical[size] = nil
+      self.objects[size] = nil
    else
-      local other = self.numerical[size]
+      local other = self.objects[size]
 
-      self.numerical[index] = other
-      self.named[other]     = index
+      self.objects[index]  = other
+      self.pointers[other] = index
 
-      self.numerical[size] = nil
+      self.objects[size] = nil
    end
 
 
-   self.named[obj] = nil
+   self.pointers[obj] = nil
    self.size = size - 1
 end
 
+function List:get(index)
+   return self.objects[index]
+end
+
 function List:has(obj)
-   return self.named[obj] and true
+   return self.pointers[obj] and true
 end
 
 return setmetatable(List, {
diff --git a/fluid/system.lua b/fluid/system.lua
index eb0d775..3e91746 100644
--- a/fluid/system.lua
+++ b/fluid/system.lua
@@ -13,7 +13,7 @@ function System.new(...)
    }, System)
 
    for _, filter in pairs({...}) do
-      local pool = system:buildPool(filter)
+      local pool = system:__buildPool(filter)
       if not system[pool.name] then
          system[pool.name]                 = pool
          system.__pools[#system.__pools + 1] = pool
@@ -25,7 +25,7 @@ function System.new(...)
    return system
 end
 
-function System:buildPool(pool)
+function System:__buildPool(pool)
    local name   = "pool"
    local filter = {}
 
@@ -40,8 +40,8 @@ function System:buildPool(pool)
    return Pool(name, filter)
 end
 
-function System:checkEntity(e)
-   local systemHas = self:has(e)
+function System:__checkEntity(e)
+   local systemHas = self:__has(e)
 
    for _, pool in ipairs(self.__pools) do
       local poolHas  = pool:has(e)
@@ -50,21 +50,21 @@ function System:checkEntity(e)
       if not poolHas and eligible then
          pool:add(e)
          self:entityAddedTo(e, pool)
-         self:tryAdd(e)
+         self:__tryAdd(e)
 
          return true
       elseif poolHas and not eligible then
          pool:remove(e)
          self:entityRemovedFrom(e, pool)
-         self:tryRemove(e)
+         self:__tryRemove(e)
 
          return false
       end
    end
 end
 
-function System:tryAdd(e)
-   if not self:has(e) then
+function System:__tryAdd(e)
+   if not self:__has(e) then
       self.__all[e] = 0
       self:entityAdded(e)
    end
@@ -72,8 +72,8 @@ function System:tryAdd(e)
    self.__all[e] = self.__all[e] + 1
 end
 
-function System:tryRemove()
-   if self:has(e) then
+function System:__tryRemove()
+   if self:__has(e) then
       self.__all[e] = self.__all[e] - 1
 
       if self.__all[e] == 0 then
@@ -83,8 +83,8 @@ function System:tryRemove()
    end
 end
 
-function System:remove(e)
-   if self:has(e) then
+function System:__remove(e)
+   if self:__has(e) then
       for _, pool in ipairs(self.__pools) do
          if pool:has(e) then
             pool:remove(e)
@@ -97,7 +97,7 @@ function System:remove(e)
    end
 end
 
-function System:has(e)
+function System:__has(e)
    return self.__all[e] and true
 end
 
diff --git a/main.lua b/main.lua
index 3a680bf..b2d0441 100644
--- a/main.lua
+++ b/main.lua
@@ -31,7 +31,9 @@ end)
 
 local RectangleRenderer = System({Position, Rectangle})
 function RectangleRenderer:draw()
-   for _, e in ipairs(self.pool.numerical) do
+   for i = 1, self.pool.size do
+      local e = self.pool:get(i)
+
       local position  = e:get(Position)
       local rectangle = e:get(Rectangle)
       local color     = e:get(Color)
@@ -47,7 +49,9 @@ end
 
 local CircleRenderer = System({Position, Circle})
 function CircleRenderer:draw()
-   for _, e in ipairs(self.pool.numerical) do
+   for i = 1, self.pool.size do
+      local e = self.pool:get(i)
+
       local position = e:get(Position)
       local circle   = e:get(Circle)
       local color    = e:get(Color)
@@ -73,7 +77,7 @@ function RandomRemover:update(dt)
       if self.pool.size > 0 then
          local i = love.math.random(1, self.pool.size)
 
-         Game:removeEntity(self.pool.numerical[i])
+         Game:removeEntity(self.pool.objects[i])
       end
    end
 end