Timeframe questions

Hi,
I am writing a demo (scene.org) which has multiple parts but I'm having problems with the loop: It should go something like this :

While not ESC
do function 1 for 30 seconds
do function 2 for 10 seconds
do function 3 for 45 seconds
END WHILE

How can I allow a function to perform for only X seconds ? Thanks in advance.

This might help...

Function tens(timerval:Int)
  While timerval+10000 > MilliSecs()
	  Cls
	  DrawText "This is 10 second function",0,0
	  DrawText ((timerval+10000)-MilliSecs())/1000,0,10
	  Flip
  Wend
End Function 
Function fifteens(timerval)
  While timerval+15000 > MilliSecs()
	  Cls
	  DrawText "This is 15 second function",0,0
	  DrawText ((timerval+15000)-MilliSecs())/1000,0,10
	  Flip
  Wend
End Function
Graphics 800,600
tens(MilliSecs())
fifteens(MilliSecs())

Here is a more complicated one:

Type TFunctionHandler
	Field Time:Int  = MilliSecs()
	Field Elapsed:Int
	Field Functions:TFunction[] = New TFunction[0]
	Field Current:Int = 0
	
	Function create:TFunctionHandler()
		Local FH:TFunctionHandler = New TFunctionHandler
		Return FH
	End Function
	
	Method AddFunction(Func_(),Time:Int)
		Functions = Functions[..Functions.length+1]
		Local F:TFunction = New TFunction	
		F.Func = Func_
		F.Time = Time
		Functions[Functions.length-1] = F
	End Method
		 	
	Method Update()
		If Elapsed - Time > Functions[Current].Time Then
			Current:+1
			Time = MilliSecs()
			If Current > Functions.Length-1 Then
				Current = 0
			EndIf
		EndIf
		Functions[Current].Func()
		Elapsed = MilliSecs()	
	End Method	
			
End Type

Type TFunction

	Field Func()
	Field Time:Int
	
End Type

Graphics 800,600,0

Global Handler:TFunctionHandler = New TFunctionHandler
Handler.AddFunction(Draw1,3000)
Handler.AddFunction(Draw2,4000)
Handler.AddFunction(Draw3,2000)






While Not KeyHit(Key_Escape)
Cls

Handler.Update()
DrawText "Time : " + (Handler.Elapsed - Handler.Time),20,20

Flip
Wend

Function Draw1()
DrawText "First Massage stays for 3 sec.",200,200
End Function

Function Draw2()
DrawText "Second Massage stays for 4 sec.",200,200
End Function

Function Draw3()
DrawText "Third Massage stays for 2 sec.",200,200
End Function

I'm trying to do something similar at the moment whereby when certain other tasks are done, with any time that is remaining for a given frame I wasn to do other tasks. Problem is you have to keep checking Millisecs() a lot so that you don't overrun how much time is left. It'd be nice if there were timers that would actually trigger of functions automatically/pre-emptively.

Wow thanks I was just looking for this. I want to make damage at double strength for 30 seconds and other interesting things. Thanks guys!! :)