Topic on Talk:Tom Clancy's Splinter Cell

I’ve ran into the error where enemies get stuck on each other before and the fix for me was switching over from projector shadows to buffer shadows. After I did that, the problem went away, though I obviously needed dgVoodoo2 to render the lights correctly.

I didn’t want to edit the main page yet because I don’t know if this was just a fluke for me or if this fixes the problem for everyone else, so if anyone else can test this, that would be helpful.

Thanks.

I wrote about that bug and I was already playing with dgVoodoo and buffer shadows. When I first played the game over 10 years ago it didn't happen, so IMO it's just a bug that randomly happens.

I don't have the game installed now, but if you are in the mood for some testing, you could try lowering the framerate to 30 FPS or something with Riva Tuner Statistics Server and replay that area. Since it is some kind of physics or pathfinding bug sometimes these old games work better on lower framerate, especially since the game was designed for consoles too.

You sure it was buffer shadows in the ini and not projector? I never encountered the bug again when I switched over while projector ended up happening fairly regularly after a while. Wonder if it was a Windows 10 thing.

Framerate was never an issue as I never needed to lower the framerate for the bug once I switched shadow modes.

Still, I’m just wondering if it’s a fluke and if so, what is the actual cause of this glitch?

Yes I'm sure, I even uploaded the old shadow comparison screenshot on the Wiki page that got corrupted. You can see it in file history. I was playing on Windows 7.

https://pcgamingwiki.com/wiki/File:Splinter_Cell_shadow_fix_comparison.png

I've just tested this, first by playing though with dgVoodoo2 shadows, no problems.

Then with projector shadows, making a quicksave as I used the laptop in the compressor room, Failure, I found the Ai got stuck at the bottom of the stairwell(repeatably).

I then switched back to dgVoodoo2 and used the same quicksave, Successful, the Ai opened the doors.

So switching back to projector shadows, I added UseVsync=True to the SplinterCell.ini, Successful.

Once more with projector shadows, I removed UseVsync=True, to see if closing the game helped, Successful.

So it is possible to play though the mission with projector shadows. I don't have time to test this more thoroughly right now, but I'll try to over the next few days.

UPDATE:

Tested from start of level:

1st:Projector shadows + UseVsync, no errors, Successful.
2nd:Projector shadows, no errors, Successful.

IMO this is either a frame rate issue or, a specific series of events glitch. I'm thinking I'll focus on frame rate next, see if I can find some consistency.

ANOTHER UPDATE:

Some more testing, with MSI Afterburner and Riva Tuner Statistics Server running to both show and limit frame rate. When the game is free to run at it maximum 200fps, and frame rate stays stable(198-200fps), the Ai appears to always get stuck in the stairwell. But if the frame rate is unstable(196-200fps), the Ai appears to be able to progress up the stairs and trigger it's teleport behavior. Limiting the game to 199fps, the Ai appears to always be able to progress.

IMPORTANT NOTE:

All of the above tests have been minimal, further testing to check that none of the above are false positives or vice versa should be done. Ill be trying my best to better understand this problem, and what is the best method for replicating and mitigating it.

I did a bit of thinking, what if the AI's path finding is effected by the frame rate and how would that look different. And how do we know which frame rate results in the correct path finding.

My mind jumps straight to real time cutscenes, which Splinter Cell has only a few. The best is at the start of the Training level, where we can observe Lambert throughout the scene. And luckily differences are easy to spot, while Lambert walks down the corridor and during his final movement in the conference room(he walks from the side of the table to the end). each of the following were tested 10x

@ 30fps, 60fps: middle of corridor; stays close to the table and finds his mark.
@ 120fps, 144fps: diagonally(left to right) in corridor; takes a wide curve but finds the mark.
@ 147fps: diagonally(left to right) in corridor; 20% chance that he will have to backtrack.
@ 150fps: diagonally(left to right) in corridor; 70% chance that he will have to backtrack.
@ 200fps: diagonally(left to right) in corridor; 100% chance that he will have to backtrack.

When Lambert has to backtrack the cutscene looks terrible, like nobody cared about how it looked. I believe most will agree that 30fps and 60fps look to be the most natural looking path for Lambert to take. While at 120fps and 144fps the scene looks fine, it's only when comparing differences that they may look a little odd. So with this in mind I took a look at one other location in the game, the start of the Abattoir level. When Badri finishes his dialog and walks to the office. each of the following were tested 3x

@ 60fps: his movement is direct, to the point.
@ 120, 144fps: he takes a wider path and bumps into a concrete block.
@ 180fps: ??% chance his wide path means that he will trigger a mine, thus killing himself.
@ 200fps: his wide path means that he will trigger a mine, thus killing himself.

So with those to observations in mind, what's happening in the Vselka Infiltration level. I think we can assume that 1 or 2 of the AI are missing there mark(waypoint) and need to backtrack. While the last is still trying to move forward, thus creating a jam in the confined space.

I had planned to post a video to go with this, to help show what I'm trying to say, but my video editing skills are not that great.