Unsynchronized events - Revision history

Dr. Kylstien: /* Staying in Sync in a Multiplayer Game */

2008-09-04T21:05:09Z

Staying in Sync in a Multiplayer Game

← Older revision		Revision as of 14:05, 4 September 2008
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	Unsynchronized events are not guaranteed to happen at the same time, or at all, between different computers in a multiplayer game. Therefore, it is not safe to use ifrnd or randvar in them, because they could end up out of sequence. It is also not safe to do anything affecting gameplay in these events for the same reason. '''[[Displayrand]] is an exception''' because it does not affect the sequence used by the other commands. '''Therefore it is safe to use in unsynchronized events.''' It should not be used in other events because that would cause the same problems outlined above.		Unsynchronized events are not guaranteed to happen at the same time, or at all, between different computers in a multiplayer game. Therefore, it is not safe to use ifrnd or randvar in them, because they could end up out of sequence. It is also not safe to do anything affecting gameplay in these events for the same reason. '''[[Displayrand]] is an exception''' because it does not affect the sequence used by the other commands. '''Therefore it is safe to use in unsynchronized events.''' It should not be used in other events because that would cause the same problems outlined above.

	DO and DON'Ts:<br>		'''DOs and DON'Ts:'''<br>
	1. Do use [[randvar]],[[randvarvar]], [[ifrnd]] in '''synchronized''' events.~~<br>~~		# Do use [[randvar]],[[randvarvar]], [[ifrnd]] in '''synchronized''' events.
	2. Do use [[displayrand]], [[displayrandvar]], [[displayrandvarvar]] in '''unsynchronized''' events.<br>		# Do use [[displayrand]], [[displayrandvar]], [[displayrandvarvar]] in '''unsynchronized''' events.<br>
	3. Do not use [[randvar]],[[randvarvar]], [[ifrnd]] in '''unsynchronized''' events.~~<br>~~		# Do not use [[randvar]],[[randvarvar]], [[ifrnd]] in '''unsynchronized''' events.
	4. Do not use [[displayrand]], [[displayrandvar]], [[displayrandvarvar]] in '''synchronized''' events.~~<br>~~		# Do not use [[displayrand]], [[displayrandvar]], [[displayrandvarvar]] in '''synchronized''' events.
	5. Do not collect information in '''unsynchronized''' events that later might be used in '''synchronized''' events or actors.~~<br>~~		# Do not collect information in '''unsynchronized''' events that later might be used in '''synchronized''' events or actors.
	6. Do not use local vars(like user options) in '''synchronized''' events. The compiler will warn you about this(note: it won't if a local var is in a state).~~<br>~~		# Do not use local vars(like user options) in '''synchronized''' events. The compiler will warn you about this(note: it won't if a local var is in a state).
	7. Do not use gameplay related commands in '''unsynchronized''' events. The compiler will warn you about this(note: it won't if a local var is in a state).~~<br>~~		# Do not use gameplay related commands in '''unsynchronized''' events. The compiler will warn you about this(note: it won't if a local var is in a state).

	[[Category:Event manipulation]]		[[Category:Event manipulation]]

Dr. Kylstien: /* Staying in sync in multiplayer game */

2008-09-04T20:58:50Z

Staying in sync in multiplayer game

← Older revision		Revision as of 13:58, 4 September 2008
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	== Staying in ~~sync~~ in ~~multiplayer game~~ ==		== Staying in Sync in a Multiplayer Game ==
	(This article is also relevant to [[demos]], which work much the same way.)		(This article is also relevant to [[demos]], which work much the same way.)

Dr. Kylstien: /* Staying in sync in multiplayer game */

2008-09-04T20:55:20Z

Staying in sync in multiplayer game

← Older revision		Revision as of 13:55, 4 September 2008
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	== Staying in sync in multiplayer game ==		== Staying in sync in multiplayer game ==
			(This article is also relevant to [[demos]], which work much the same way.)

	'''~~Unsynchronized~~ events''' are ~~not synchronized~~ in ~~multiplayer~~ game ~~as they~~ are usually triggered only a local computer so the CON code doesn't have to work the same way on different computers. These events usually ~~are~~ display related or ~~have effect~~ only on the ~~current~~ computer.		'''Synchronized events''' are always triggered on all computers at the same time and under the same conditions, triggered on specific in-game situations. '''Unsynchronized events''', however, are usually triggered on only the local computer so the CON code doesn't have to work the same way on different computers. These events are usually display-related or affect only the local computer.

	~~'''Synchronized events''' always triggered on all computers at the same time and at the same conditions. These events triggers on specific ingame situations.~~

	~~=== Random Numbers and Multiplayer Sync ===~~

	In order to understand the interaction of random occurrences and unsynchronized events, you need to understand two things:		In order to understand the interaction of random occurrences and unsynchronized events, you need to understand two things:
	# [[randvar]] and [[ifrnd]] are NOT RANDOM. They step through a pre-determined sequence of numbers that appear to be random.		# [[randvar]] and [[ifrnd]] are '''NOT RANDOM'''. They step through a pre-determined sequence of numbers that appear to be random.
	# In multiplayer, ''very little'' information is shared between the different computers.		# In multiplayer, very little information is shared between the different computers. Each computer runs an ''almost independent'' instance of the game, sharing only information about the actions of the players. '''They do not share the outcomes of ifrnd or randvar.'''

	~~Every time something "random" happens in the game, it must happen the ''~~'~~same way~~''' ~~on all~~ of the ~~computers. Since all of them start with~~ the ~~same number and go through the same sequence~~ of ~~numbers at~~ the ~~same times, everything works~~. ~~But if one computer calls [[ifrnd]] or [[randvar]] while the others~~ do not~~, it ends up at a different place in the random sequence. The next time something random happens in the game, it occurs differently on this computer, causing~~ the ~~game to become '''out-~~of~~-sync'''~~. ~~(This isn~~'~~t even the worst case: Imagine~~ ''~~each computer'' on a ''wildly'' different place in the sequence.)~~

	~~Unsynchronized events are not guaranteed to~~ happen at the same ~~time~~, or at ~~all, between~~ different ~~computers~~ in ~~a multiplayer~~ game~~. Therefore~~, it ~~is not safe~~ to ~~use [[ifrnd]] or [[randvar]] in them, because they could end up~~ out of sequence~~. It is also not safe to do anything affecting gameplay~~ in ~~these events for~~ the ~~same reason~~.		Every time something "random" happens in the game, it '''must happen the same way''' on all of the computers. Since all of them start with the same number and go through the same sequence of numbers at the same times, everything works. But if one computer calls ifrnd or randvar while the others do not, it ends up at a different place in the random sequence. The next time something random happens in the game, it occurs differently on this computer, causing the game to become '''out-of-sync'''. (This isn't even the worst case: Imagine ''each computer'' on a ''wildly'' different place in the sequence, resulting in almost no correlation between what each player sees in the game.)

	[[Displayrand]] is an exception because it does not affect the sequence used by the other commands. Therefore it is safe to use in unsynchronized events. It should not be used in other events because that would cause the same problems outlined above.		Unsynchronized events are not guaranteed to happen at the same time, or at all, between different computers in a multiplayer game. Therefore, it is not safe to use ifrnd or randvar in them, because they could end up out of sequence. It is also not safe to do anything affecting gameplay in these events for the same reason. '''[[Displayrand]] is an exception''' because it does not affect the sequence used by the other commands. '''Therefore it is safe to use in unsynchronized events.''' It should not be used in other events because that would cause the same problems outlined above.

	~~===~~DO and DON'Ts~~===~~		DO and DON'Ts:<br>
	1. Do use [[randvar]],[[randvarvar]], [[ifrnd]] in '''synchronized''' events.<br>		1. Do use [[randvar]],[[randvarvar]], [[ifrnd]] in '''synchronized''' events.<br>
	2. Do use [[displayrand]], [[displayrandvar]], [[displayrandvarvar]] in '''unsynchronized''' events.<br>		2. Do use [[displayrand]], [[displayrandvar]], [[displayrandvarvar]] in '''unsynchronized''' events.<br>

68.200.49.39: /* Staying in sync in multiplayer game */

2008-09-04T20:33:46Z

Staying in sync in multiplayer game

@@ Line 5: / Line 5: @@
 '''Synchronized events''' always triggered on all computers at the same time and at the same conditions. These events triggers on specific ingame situations.
-DO and DON'Ts:<br>
+=== Random Numbers and Multiplayer Sync ===
 . Do use [[randvar]],[[randvarvar]], [[ifrnd]] in '''synchronized''' events.<br>
 . Do use [[displayrand]], [[displayrandvar]], [[displayrandvarvar]] in '''unsynchronized''' events.<br>

Hunter byte: New page: == Staying in sync in multiplayer game == '''Unsynchronized events''' are not synchronized in multiplayer game as they are usually triggered only a local computer so the CON code doesn't ...

2008-08-31T17:22:28Z

New page: == Staying in sync in multiplayer game == '''Unsynchronized events''' are not synchronized in multiplayer game as they are usually triggered only a local computer so the CON code doesn't ...

New page

== Staying in sync in multiplayer game ==

'''Unsynchronized events''' are not synchronized in multiplayer game as they are usually triggered only a local computer so the CON code doesn't have to work the same way on different computers. These events usually are display related or have effect only on the current computer.

'''Synchronized events''' always triggered on all computers at the same time and at the same conditions. These events triggers on specific ingame situations.

DO and DON'Ts: 
1. Do use [[randvar]],[[randvarvar]], [[ifrnd]] in '''synchronized''' events. 
2. Do use [[displayrand]], [[displayrandvar]], [[displayrandvarvar]] in '''unsynchronized''' events. 
3. Do not use [[randvar]],[[randvarvar]], [[ifrnd]] in '''unsynchronized''' events. 
4. Do not use [[displayrand]], [[displayrandvar]], [[displayrandvarvar]] in '''synchronized''' events. 
5. Do not collect information in '''unsynchronized''' events that later might be used in '''synchronized''' events or actors. 
6. Do not use local vars(like user options) in '''synchronized''' events. The compiler will warn you about this(note: it won't if a local var is in a state). 
7. Do not use gameplay related commands in '''unsynchronized''' events. The compiler will warn you about this(note: it won't if a local var is in a state). 

[[Category:Event manipulation]]