Open TheLastRar opened 1 month ago
sestain
commented
1 month ago test 1: https://youtu.be/sv9F0htCuIs test 2: https://youtu.be/VZMQQWi-0WI compare: https://youtu.be/tLno1EW0cvY Compare maybe has like 1 frame difference, but it's so small it's almost unnoticeable. Also it didn't desync for me, so technically I couldn't reproduce the issue even though it had 1 frame difference between playbacks but it synced.
kage2051
commented
1 month ago Something tells me it's the CDVD side causing the frame drift. I remember a similar case with 3DS TASing where most of the desyncs were caused by I/O depending on host disk transfer rate, even if it's being playback'd on the same computer. Which was fixed at least for the ported core on BizHawk dev builds.
TheLastRar
commented
1 month ago test 1: https://youtu.be/sv9F0htCuIs test 2: https://youtu.be/VZMQQWi-0WI compare: https://youtu.be/tLno1EW0cvY Compare maybe has like 1 frame difference, but it's so small it's almost unnoticeable. Also it didn't desync for me, so technically I couldn't reproduce the issue even though it had 1 frame difference between playbacks but it synced.
I tested Crash TwinSanity and it didn't suffer from this bug, it played back consistently for me
Something tells me it's the CDVD side causing the frame drift. I remember a similar case with 3DS TASing where most of the desyncs were caused by I/O depending on host disk transfer rate, even if it's being playback'd on the same computer. Which was fixed at least for the ported core on BizHawk dev builds.
I had initially suspected something on the SPU side (as the effected tutorial plays for the duration of a voice line, along with the other issue of de-synced subs), but it could easily be something else
Describe the Bug
Emulation is inconsistent can cause two playbacks of the same input recording to behaviours differently
Discovered when playing back a recording of me playing the tutorial for Jak X (PAL)
Playback will typically desync during the second tutorial, where the tutorial prompt freezes the game while you are in motion
In run 1, this tutorial was starts on frame 9248 and (slowly) starts to unpause on frame 9499 In run 2, this tutorial was starts on frame 9248 and (slowly) starts to unpause on frame 9500
As this tutorial occurs while you are motion, the recorded inputs and the car position become desynced.
The following drift is (possible as a result?) then exasperates the desync, as run 2 exists the drift a frame earlier, does not re-enter the drift and as a result leaves the tunnel miss-aligned from the 1st run.
Other de-syncs observed but didn't have a visible gameplay affect are; 2 lines of subtitles (frame 3684 & 4206) are delayed by 2 frames, despite other subtitles and the camera movements being in sync Differences in visual effects (particles and the movement of the pickups)
Run 1 (Tutorial 2 starts at 3mins in) https://youtu.be/6aL6yC8rbdU
Run 2 (Tutorial 2 starts at 3mins in) https://youtu.be/GuAlRCYPGKw
A Comparison (Tutorial 2 starts at 3mins in) https://youtu.be/P9d-MLa-HII The comparison is made using the following command
ffmpeg -y -i "vid1.mp4" -i "vid2.mp4" -filter_complex '[1:v]format=yuva444p,lut=c3=128,negate[video2withAlpha],[0:v][video2withAlpha]overlay[out]' -map [out] "compare.mp4"The input recording file JakXTestRecording.zip
Reproduction Steps
Using either the attached recording file, or your own recording file
The video capture was produced using the following steps;
Expected Behavior
Playback of input recording files to result in consistent behaviour
PCSX2 Revision
Recordings from #11590, bug verified to exist on v2.1.18
Operating System
Windows 11
If Linux - Specify Distro
No response
CPU
AMD Ryzen 9 7950X3D
GPU
RTX 4080
GS Settings
No response
Emulation Settings
Pause On Start: Enabled Fast Boot: Enabled Memory Card Slots 1 & 2: Ejected + Disabled
GS Window Screenshots
No response
Logs & Dumps
emulog.txt