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Double Linked list and optimization... - Gideros Forum

Double Linked list and optimization...

GregBUGGregBUG Guru
edited February 2012 in General questions
hey guys!!!

in my particle engine i'm trying to optimize at my best to try to squeeze all possible fps from my devices...

in current implementation i use a table (fixed) and work quite well.

i tryed to implement a linked list to optimize more but some test demostrate that table are much faster...

here is the code to test: the linked list code ("strongly inspired" from a book that i'm reading)
CDLinkedList = Core.class()
 
----------------------------
-- Init width a void list --
----------------------------
function CDLinkedList:init()
	self.list = {
		first		= nil, 
		last		= nil,
	}
	self.itemsCount = 0
end
 
-----------------------------
-- add an item to the list --
-----------------------------
function CDLinkedList:add(objectData)
	self.newItem = {
		prev = nil, 
		next = self.list.first, 
		data = objectData
	}
	self.itemsCount = self.itemsCount + 1
	if not self.list.first then
		self.list.first = self.newItem
		self.list.last = self.newItem
	else
		self.list.first.prev = self.newItem
		self.list.first = self.newItem
	end
end
 
--------------------------------
-- delete an item to the list --
--------------------------------
function CDLinkedList:delete(node)
	if node == self.list.first then
		self.list.first = node.next
	else
		node.prev.next = node.next
	end
 
	if node == self.list.last then
		self.list.last = node.prev
	else
		node.next.prev = node.prev
	end
	self.itemsCount = self.itemsCount - 1
end
 
-------------------------------
-- for iterate with for loop --
-------------------------------
function getNext(list, node)
	return (not node and list.last) or node.prev
end
ù
 
 
--- TEST ---
 
 
 
local mylist = CDLinkedList.new()
 
s = os.timer()
for j = 1, 1000000 do
	mylist:add(j)
end
 
for node in getNext, mylist.list do
  --- no ops
end
 
 
e = os.timer()
 
print(e-s)
 
 
--[[
a = {}
s = os.timer()
for j = 1, 1000000 do
	a[j] = j
end
 
for j = 1, 1000000 do
	---- no ops
end
 
e = os.timer()
print (e-s)
--]]
the code with linked list took on my pc about 2.5 secs

the code with table about 0.10 secs

What am I doing wrong?
any advice?
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