Pause Cutscene Trigger - Revision history

Ruh at 01:43, 7 July 2024

2024-07-07T01:43:25Z

← Older revision		Revision as of 01:43, 7 July 2024
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	'''~~Pause~~ cutscene trigger''', or '''~~pause triggering~~''', is a bug that allows Jak to initiate the audio stream of a queued "event" without triggering the full "event". The bug is most commonly used on the second to last mirror in Forbidden Jungle to trigger the fisherman cutscene audio stream early, but it can be performed with any streamed audio file.		A '''pause cutscene trigger''', also known as a '''pause trigger''' or '''audio buffer''', is a bug that allows Jak to initiate the audio stream of a queued "event" without triggering the full "event". The bug is most commonly used on the second to last mirror in Forbidden Jungle to trigger the fisherman cutscene audio stream early, but it can be performed with any streamed audio file.

	It was [https://github.com/open-goal/jak-project/blob/master/game/overlord/jak1/iso.cpp#L758 patched] in the OpenGOAL PC port of the game by Dass because it would cause occasional crashes. "The console version does not crash because the PS2 IOP can handle null derefs."		It was [https://github.com/open-goal/jak-project/blob/master/game/overlord/jak1/iso.cpp#L758 patched] in the OpenGOAL PC port of the game by Dass because it would cause occasional crashes. "The console version does not crash because the PS2 IOP can handle null derefs."

Ruh at 19:36, 6 July 2024

2024-07-06T19:36:38Z

← Older revision		Revision as of 19:36, 6 July 2024
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	'''Pause cutscene trigger''', or '''pause triggering''', is a bug that allows Jak to initiate the audio stream of a queued "event" without triggering the full "event". The bug is most commonly used on the second to last mirror in Forbidden Jungle to trigger the fisherman cutscene audio stream early.		'''Pause cutscene trigger''', or '''pause triggering''', is a bug that allows Jak to initiate the audio stream of a queued "event" without triggering the full "event". The bug is most commonly used on the second to last mirror in Forbidden Jungle to trigger the fisherman cutscene audio stream early, but it can be performed with any streamed audio file.

	It was [https://github.com/open-goal/jak-project/blob/master/game/overlord/jak1/iso.cpp#L758 patched] in the OpenGOAL PC port of the game by Dass because it would cause occasional crashes. "The console version does not crash because the PS2 IOP can handle null derefs."		It was [https://github.com/open-goal/jak-project/blob/master/game/overlord/jak1/iso.cpp#L758 patched] in the OpenGOAL PC port of the game by Dass because it would cause occasional crashes. "The console version does not crash because the PS2 IOP can handle null derefs."

Ruh at 19:35, 6 July 2024

2024-07-06T19:35:46Z

← Older revision		Revision as of 19:35, 6 July 2024
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	'''Pause cutscene trigger''', or '''pause triggering''', is a bug that allows Jak to initiate the audio stream of a queued "event" without triggering the full "event". The bug is most commonly used		'''Pause cutscene trigger''', or '''pause triggering''', is a bug that allows Jak to initiate the audio stream of a queued "event" without triggering the full "event". The bug is most commonly used on the second to last mirror in Forbidden Jungle to trigger the fisherman cutscene audio stream early.

	It was [https://github.com/open-goal/jak-project/blob/master/game/overlord/jak1/iso.cpp#L758 patched] in the OpenGOAL PC port of the game by Dass because it would cause occasional crashes. "The console version does not crash because the PS2 IOP can handle null derefs."		It was [https://github.com/open-goal/jak-project/blob/master/game/overlord/jak1/iso.cpp#L758 patched] in the OpenGOAL PC port of the game by Dass because it would cause occasional crashes. "The console version does not crash because the PS2 IOP can handle null derefs."

Ruh at 19:34, 6 July 2024

2024-07-06T19:34:59Z

← Older revision		Revision as of 19:34, 6 July 2024
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	'''Pause cutscene trigger''', or '''pause triggering''', is a bug that allows Jak to initiate the audio stream of a queued "event" without triggering the full "event".		'''Pause cutscene trigger''', or '''pause triggering''', is a bug that allows Jak to initiate the audio stream of a queued "event" without triggering the full "event". The bug is most commonly used

	~~The trick~~ was [https://github.com/open-goal/jak-project/blob/master/game/overlord/jak1/iso.cpp#L758 patched] in the OpenGOAL PC port of the game by Dass because it would cause occasional crashes. "The console version does not crash because the PS2 IOP can handle null derefs."		It was [https://github.com/open-goal/jak-project/blob/master/game/overlord/jak1/iso.cpp#L758 patched] in the OpenGOAL PC port of the game by Dass because it would cause occasional crashes. "The console version does not crash because the PS2 IOP can handle null derefs."

	== Technical ==		== Technical ==

Ruh at 19:32, 6 July 2024

2024-07-06T19:32:02Z

← Older revision		Revision as of 19:32, 6 July 2024
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	'''Pause cutscene trigger''', or '''pause triggering''', is a bug that allows Jak to initiate the audio of a ~~cutscene~~ without ~~entering~~ the ~~cutscene itself~~.		'''Pause cutscene trigger''', or '''pause triggering''', is a bug that allows Jak to initiate the audio stream of a queued "event" without triggering the full "event".

	The trick was [https://github.com/open-goal/jak-project/blob/master/game/overlord/jak1/iso.cpp#L758 patched] in the OpenGOAL PC port of the game by Dass because it would cause occasional crashes. "The console version does not crash because the PS2 IOP can handle null derefs."		The trick was [https://github.com/open-goal/jak-project/blob/master/game/overlord/jak1/iso.cpp#L758 patched] in the OpenGOAL PC port of the game by Dass because it would cause occasional crashes. "The console version does not crash because the PS2 IOP can handle null derefs."
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	== Technical ==		== Technical ==
	<blockquote>		<blockquote>
	''In order to prevent freezes when the game wants to start any streamed file, <code>actors</code> that want to use any sort of streamed data will attempt to put themselves in the stream loader's queue, which sorts streams based on priority (3 streams, lower values first). 99% of the time, priority is set to the distance to the <code>actor</code> that wants to queue up a stream, which means closer <code>actors</code> get put higher on the list, or a negative value if it's something that's already playing (which guarantees a higher priority as distances cannot be negative). The stream at the top of the list that's not already playing (the preload stream) will then be sent to <code>OVERLORD</code> as the one that should be queued up and prepared for loading.		''In order to prevent freezes when the game wants to start any streamed file, <code>actors</code> that want to use any sort of streamed data will attempt to put themselves in the stream loader's queue, which sorts streams based on priority (3 streams, lower values first). 99% of the time, priority is set to the distance to the <code>actor</code> that wants to queue up a stream, which means closer <code>actors</code> get put higher on the list, or a negative value if it's something that's already playing (which guarantees a higher priority as distances cannot be negative). The stream at the top of the list that's not already playing (the preload stream) will then be sent to <code>OVERLORD</code> as the one that should be queued up and prepared for loading.''

	However, because <code>OVERLORD</code> kinda sucks, when a stream finishes playing the <code>GOAL</code> thread will not be aware of this before <code>OVERLORD</code>, so if you (un)pause on the frame that it ends, it will end up sending an "unpause" message to <code>OVERLORD</code> despite there being nothing to unpause. This causes whatever the game is about to queue up next to be the stream that receives that message instead (as queued up streams are effectively no different to ones that are playing, they're paused by default). So, the queued up stream starts playing and causes audio to start playing unexpectedly (for streams that have audio).		''However, because <code>OVERLORD</code> kinda sucks, when a stream finishes playing the <code>GOAL</code> thread will not be aware of this before <code>OVERLORD</code>, so if you (un)pause on the frame that it ends, it will end up sending an "unpause" message to <code>OVERLORD</code> despite there being nothing to unpause. This causes whatever the game is about to queue up next to be the stream that receives that message instead (as queued up streams are effectively no different to ones that are playing, they're paused by default). So, the queued up stream starts playing and causes audio to start playing unexpectedly (for streams that have audio).''

	Now, when you, for example, go to the NPC that the audio belongs to, the game engine syncs up the cutscenes by using the information from <code>OVERLORD</code> about where in the stream playback we are. So, the cutscene just jumps to whatever the audio is at and things resume as normal.''		''Now, when you, for example, go to the NPC that the audio belongs to, the game engine syncs up the cutscenes by using the information from <code>OVERLORD</code> about where in the stream playback we are. So, the cutscene just jumps to whatever the audio is at and things resume as normal.''

	- Dass		- Dass

Ruh: /* Technical */

2024-07-06T19:27:49Z

Technical

← Older revision		Revision as of 19:27, 6 July 2024
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	== Technical ==		== Technical ==
	<blockquote>		<blockquote>
	''~~I don't think anybody knows~~ the ~~exact reason for~~ that ~~trick, but it's very likely related~~ to ~~a bug~~ in ~~how~~ the ~~main CPU and the "overlord" driver running~~ on the ~~I/O processor are synchronized. In OpenGOAL~~, the ~~timing of all this stuff is a lot different, since modern PCs are a lot faster. Maybe you have~~ to ~~pause while~~ a ~~certain thing is loading~~, ~~and~~ on ~~console~~, that ~~might~~ be ~~a window~~ of ~~multiple frames. But on PC,~~ the ~~loading is so fast~~ that ~~there~~'s ~~no window~~.''		''In order to prevent freezes when the game wants to start any streamed file, <code>actors</code> that want to use any sort of streamed data will attempt to put themselves in the stream loader's queue, which sorts streams based on priority (3 streams, lower values first). 99% of the time, priority is set to the distance to the <code>actor</code> that wants to queue up a stream, which means closer <code>actors</code> get put higher on the list, or a negative value if it's something that's already playing (which guarantees a higher priority as distances cannot be negative). The stream at the top of the list that's not already playing (the preload stream) will then be sent to <code>OVERLORD</code> as the one that should be queued up and prepared for loading.

	~~''Some~~ the ~~windows aren't tied to~~ the ~~PC speed - like the fire canyon one~~, ~~since~~ the game is ~~checking the position once per frame. But stuff related~~ to ~~loading/sound is basically running independently and could~~ be ~~quite a bit~~ different ~~between opengoal/console~~. ~~Which is kind of a nightmare~~ for ~~us, since on PC, it may run way faster, triggering bugs~~ that ~~were in the original game but could never happen on original hardware~~.''		However, because <code>OVERLORD</code> kinda sucks, when a stream finishes playing the <code>GOAL</code> thread will not be aware of this before <code>OVERLORD</code>, so if you (un)pause on the frame that it ends, it will end up sending an "unpause" message to <code>OVERLORD</code> despite there being nothing to unpause. This causes whatever the game is about to queue up next to be the stream that receives that message instead (as queued up streams are effectively no different to ones that are playing, they're paused by default). So, the queued up stream starts playing and causes audio to start playing unexpectedly (for streams that have audio).

	- ~~Water111~~		Now, when you, for example, go to the NPC that the audio belongs to, the game engine syncs up the cutscenes by using the information from <code>OVERLORD</code> about where in the stream playback we are. So, the cutscene just jumps to whatever the audio is at and things resume as normal.''

			- Dass
	</blockquote>		</blockquote>

Ruh at 18:55, 6 July 2024

2024-07-06T18:55:13Z

← Older revision		Revision as of 18:55, 6 July 2024
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	'''Pause cutscene trigger''', or '''pause triggering''', is a bug that allows Jak to initiate the audio of a cutscene without entering the cutscene itself.		'''Pause cutscene trigger''', or '''pause triggering''', is a bug that allows Jak to initiate the audio of a cutscene without entering the cutscene itself.

			The trick was [https://github.com/open-goal/jak-project/blob/master/game/overlord/jak1/iso.cpp#L758 patched] in the OpenGOAL PC port of the game by Dass because it would cause occasional crashes. "The console version does not crash because the PS2 IOP can handle null derefs."

	== Technical ==		== Technical ==
	~~Hypothesis on why the trick works on console but not the PC port.~~

	<blockquote>		<blockquote>
	''I don't think anybody knows the exact reason for that trick, but it's very likely related to a bug in how the main CPU and the "overlord" driver running on the I/O processor are synchronized. In OpenGOAL, the timing of all this stuff is a lot different, since modern PCs are a lot faster. Maybe you have to pause while a certain thing is loading, and on console, that might be a window of multiple frames. But on PC, the loading is so fast that there's no window.''		''I don't think anybody knows the exact reason for that trick, but it's very likely related to a bug in how the main CPU and the "overlord" driver running on the I/O processor are synchronized. In OpenGOAL, the timing of all this stuff is a lot different, since modern PCs are a lot faster. Maybe you have to pause while a certain thing is loading, and on console, that might be a window of multiple frames. But on PC, the loading is so fast that there's no window.''

Ruh at 18:50, 6 July 2024

2024-07-06T18:50:23Z

← Older revision		Revision as of 18:50, 6 July 2024
Line 1:		Line 1:
	'''Pause cutscene trigger''', or '''pause triggering''', is a bug that allows Jak to initiate the audio of a cutscene without entering the cutscene itself.		'''Pause cutscene trigger''', or '''pause triggering''', is a bug that allows Jak to initiate the audio of a cutscene without entering the cutscene itself.


	~~== Demonstrations ==~~
	~~<youtube>https://www.youtube.com/watch?v=K-XbOQNA_AE</youtube>~~

	~~<youtube>https://www.youtube.com/watch?v=y4csOk3GUdM</youtube>~~

	== Technical ==		== Technical ==
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	- Water111		- Water111
	</blockquote>		</blockquote>

			== Demonstrations ==
			<youtube>https://www.youtube.com/watch?v=K-XbOQNA_AE</youtube>

			<youtube>https://www.youtube.com/watch?v=y4csOk3GUdM</youtube>

	== Discovery ==		== Discovery ==

Ruh at 18:50, 6 July 2024

2024-07-06T18:50:08Z

← Older revision		Revision as of 18:50, 6 July 2024
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	== Demonstrations ==		== Demonstrations ==
	<youtube>https://www.youtube.com/watch?v=K-XbOQNA_AE</youtube>		<youtube>https://www.youtube.com/watch?v=K-XbOQNA_AE</youtube>

	<youtube>https://www.youtube.com/watch?v=y4csOk3GUdM</youtube>		<youtube>https://www.youtube.com/watch?v=y4csOk3GUdM</youtube>

Ruh at 18:50, 6 July 2024

2024-07-06T18:50:04Z

← Older revision		Revision as of 18:50, 6 July 2024
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			== Demonstrations ==
	<youtube>https://www.youtube.com/watch?v=K-XbOQNA_AE</youtube>		<youtube>https://www.youtube.com/watch?v=K-XbOQNA_AE</youtube>
			<youtube>https://www.youtube.com/watch?v=y4csOk3GUdM</youtube>

	== Technical ==		== Technical ==