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		  		 Bind a Dll to LuaEdit (Tutorial) - Managing the Game
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							<b><font face="Tahoma" size="3" color="navy">Managing the Game</font></b>
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							 <a href="http://www.lua.org">Lua homepage</a>
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							Now the script contains a solid basic frame/structure around which we will add
							code to actually handle the game. This means sequence randomization algorythms,
							key validations, point system logic, etc. Let's start by the game initialization
							routine.
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						  	The simon:Initialize() function previously added will be called right before a new game is
							requested by the player. Our main goal in this function is to reset all of our game handling variables
							previously created and intialize random logic. In the world of computers, generating
							random is not an easy thing to achieve. Let's be realistic, it's impossible to recreate
							exactly what random is by definition. On the other hand, we can generate something
							so huge in terms of quantity of possibilities, that statistically and humanly speaking, we can
							call this random. Lua's pseudo-random engine works the same way as in C++.
							In fact, "behind the scene", Lua uses the C++ pseudo-random engine. This engine works
							with seeds to generate "random" sequences of numbers. A seed is a number which will
							be used to generate "random" numbers. In other words, two sequences using the same seed will
							be identical. To avoid this problem, many scripts/programs use the system's current time
							as the random seed, which pratically makes it impossible for the user to get or even remember
							having the same sequence. Here is how the simon:Initialize() function should look like:
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							-- Initialize the game<br>
							function simon:Initialize()<br>
								&nbsp;&nbsp;&nbsp;&nbsp;-- Initalize variables<br>
								&nbsp;&nbsp;&nbsp;&nbsp;simon:SetScore(0)<br>
								&nbsp;&nbsp;&nbsp;&nbsp;GameState = true<br>
								&nbsp;&nbsp;&nbsp;&nbsp;UserSequenceCount = 0<br>
								&nbsp;&nbsp;&nbsp;&nbsp;SequenceCount = 0<br>
								&nbsp;&nbsp;&nbsp;&nbsp;MainSequence = {}<br><br>
								
								&nbsp;&nbsp;&nbsp;&nbsp;-- Initialize random engine<br>
								&nbsp;&nbsp;&nbsp;&nbsp;math.randomseed(os.time())<br>
								&nbsp;&nbsp;&nbsp;&nbsp;math.random()<br>
								&nbsp;&nbsp;&nbsp;&nbsp;math.random()<br>
								&nbsp;&nbsp;&nbsp;&nbsp;math.random()<br>
							end<br>
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						  	In this previous code example, math.random() function is called three times because under
							some operating systems (at least in Windows 2k<sup>®</sup>) the first random number you get is not really
							"randomized". (Source taken from the <a href="http://lua-users.org/wiki/MathLibraryTutorial">lua-users wiki</a> website)
							 To get better pseudo-random numbers, we just pop some random numbers before using
							them for real. The other lines of code in that previous example initialize the variables previously
							declared in the <a href=".\Page2_En.html">step 2</a> of this tutorial. Next, let's add some code
							in the simon:AddSequence(Sequence) function. The goal of this function is to append a new item to
							the sequence that the player is going to have to reproduce later. To do so, we will increment by 1
							the global variable SequenceCount and we will "randomize" a number from 1 to 4. That generated number
							is going to represent the light to turn on in the sequence. Here is how the function should looks like:
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							-- Add one more part to the game's sequence<br>
							function simon:AddSequence()<br>
								&nbsp;&nbsp;&nbsp;&nbsp;SequenceCount = SequenceCount + 1<br>
							    &nbsp;&nbsp;&nbsp;&nbsp;MainSequence[SequenceCount] = math.random(4)<br>
							end<br>
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						  	 Next, we will fill the simon:PlaySequence(Sequence) function. The main goal of
							 this function is to play the sequence previously built via calls to the
							 Simon<sup>®</sup> game's engine exported functions. In this function, we should
							 parse the sequence table item by item and turn on the light that this item is worth.
							 Let's be more specific:
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							-- Play the game's sequence<br>
							function simon:PlaySequence(Sequence)<br>
								&nbsp;&nbsp;&nbsp;&nbsp;local v = nil<br>
								&nbsp;&nbsp;&nbsp;&nbsp;local i = nil<br><br>
								
								&nbsp;&nbsp;&nbsp;&nbsp;-- Lock controls from user to make sure no conflicts happened while palying sequence<br>
								&nbsp;&nbsp;&nbsp;&nbsp;simon.LockControls()<br><br>
								
								&nbsp;&nbsp;&nbsp;&nbsp;-- Play all sequence<br>
							    &nbsp;&nbsp;&nbsp;&nbsp;repeat<br>
							    	&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;simon.SetLight(SIMON_NONE)<br>
							    	&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Sleep(300)<br>
									&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;i, v = next(Sequence, i)<br>
									&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;simon.SetLight(v)<br><br>
							
									&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;if i ~= nil then<br>
										&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Sleep(500)<br>
									&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;end<br>
							    &nbsp;&nbsp;&nbsp;&nbsp;until i == nil<br><br>
							    
							    &nbsp;&nbsp;&nbsp;&nbsp;simon.UnlockControls()<br>
							    &nbsp;&nbsp;&nbsp;&nbsp;simon.SetLight(SIMON_NONE)<br>
							end<br>
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						  	 The two local variables v and i are going to be use to retrieve the result
							 of our calls to the next() function. The next() function is used to retrieve the
							 next element in a lua table by specifiying the actual table and the index of
							 the current element as parameters. The simon.LockControls() and simon.UnlockControls() functions
							 are exported from the game's engine and their main goal is to lock/unlock the
							 controls from the player to avoid any conflict in the code. In the previous example
							 of code, the calls to the simon.LockControls() and simon.UnlockControls() functions will be made before and after the loop that is actually
							 displaying the sequence to the player. Also, in the code sample the "repeat...until"
							 statement was used to allow the code to enter in the loop for the first iteration
							 everytime it has to but any other loop syntax would have been a proper use as well.
							 The first chunk in the loop is a call to the simon.SetLight() function using
							 SIMON_NONE as first and only parameter. This instruction will turn off all the lights
							 in the game because we want to make sure that for each item no other light but the one
							 of the current item will be on. Next, we have a Sleep() call of 300 miliseconds as
							 the argument. This call, unlike the one in <a href=".\Page2_En.html">step 2</a> of
							 this tutorial, has the same effect on the computer but is more used as a "pause"
							 feature than a CPU "slower" kind of feature. With what has been clarify so far,
							 you should be able to understand the remaining lines that I didn't detailed.
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						  <p style="text-align:justify"> 
						  	 To finalize this step we will add some code to the simon:OnButtonClick(ButtonIndex)
							 function. This function will be called by the Simon<sup>®</sup> game's engine every time
							 the player pushes one of the four buttons in the game. Our main goal in that function
							 is to validate the pushed button and start managing points for an eventual victory.
							 To do so, the functions simon.GetScore() and simon.SetScore() will be used. View the
							 simplicity of this function and the advancement in the tutorial, this function will
							 not be explained in details. Just remember what we've dicussed so far in the turorial:
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							-- Event handler called by simon.dll when any of the colored buttons are clicked<br>
							function simon:OnButtonClick(ButtonIndex)<br>
								&nbsp;&nbsp;&nbsp;&nbsp;local Result = 0<br>
								&nbsp;&nbsp;&nbsp;&nbsp;UserSequenceCount = UserSequenceCount + 1<br><br>
								
								&nbsp;&nbsp;&nbsp;&nbsp;if MainSequence[UserSequenceCount] == ButtonIndex then<br>
									&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;simon.SetScore(simon.GetScore() + 10)<br>
								    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Result = 1<br>
								&nbsp;&nbsp;&nbsp;&nbsp;end<br><br>
								
								&nbsp;&nbsp;&nbsp;&nbsp;return Result<br>
							end<br>
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						  	 In the next step of this tutorial, we will discuss more about controling the
							 game in the main loop and linking the functions from the C/C++/Delphi dll file.
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