[2.0.75] Space platform fog layer stretches vertically / animation skips over time

[malventano]

I've noted that the space platform fog layer skips by a larger number of vertical pixels over time, and the graphic itself also gets stretched out vertically. The skips are most noticeable when the ship has stopped, where the animation would normally be very slowly (and smoothly) scrolling downward. Letting the game run over a week, I noticed the animation skipping by larger and larger numbers of pixels at a time, and that the skipping was accompanied by the fog layer graphic itself stretching vertically.

System is Windows 11, RTX 5090 - driver 591.74. Smooth Motion enabled in Nvidia app (but should have no impact on this texture behavior).

Screen shots captured below (doesn't show the animation skip but shows the distortion of the layer's graphic):
Distorted behavior:

20260303-141428-.png (608.05 KiB) Viewed 404 times

Normal behavior:

20260303-141524-.png (1019.78 KiB) Viewed 404 times

Nothing else in game was impacted, and the image returns to normal after restarting the game.

[Rseding91]

How can I reproduce this?

[malventano]

How can I reproduce this?

I had the game running for over a week before I noticed the effect get obvious enough to troubleshoot. Restarting Factorio and loading the save does not repro, so that will do no good here. I took the opportunity to update drivers to the newest 595.71 and start from a clean boot. I will continue to monitor. Now that I know what to look for, and that the issue seemed to progress relatively linearly over time, I should be able to spot the difference after a few days of runtime. If it repros, I will capture some video as it is much more obvious in motion.

Also note, this is a Space Age playthrough with no mods.

More to follow.

[malventano]

After running overnight the stuttery animation is starting to present. Note the fog layer intermittently stalls and then skips ahead as you step through frames. The behavior feels like there is some integer rounding related to the fog position that is amplified as the game progresses over time.
It will likely take several more days before it progresses to the point where the texture stretches vertically. Will continue to monitor.

2026-03-04 11-46-01.mp4

(5.36 MiB) Downloaded 13 times

[Rseding91]

Can you upload the save file you're using?

[malventano]

Can you upload the save file you're using?

Sure thing. Attached. This save is running with Factorio (now 2.0.76) in a maximized window (not full screen), which is typically minimized overnight, with the system display allowed to sleep (since Factorio normally forces the display to stay awake) by configuring the host as follows:
`powercfg /requestsoverride PROCESS factorio.exe DISPLAY`

Also did another capture as it's been 2 days since restarting and the stuttery behavior has increased further, which is consistent with prior repro. Note the fog texture has slightly stretched vertically and skips by a greater number of pixels as compared with before:

2026-03-05 13-15-08.mp4

(5.11 MiB) Downloaded 6 times

Save:

Dunigan2-123.zip

(32.62 MiB) Downloaded 3 times

Graphics settings for reference:

20260305-131913.png (199.65 KiB) Viewed 152 times

[Rseding91]

Is there anything I need to do? The platform is currently paused when I load it.

[malventano]

Is there anything I need to do? The platform is currently paused when I load it.

I'm not sure if having it unpaused or not matters for the bug, but the two times that I have repro-d the issue, the platform was unpaused. I only paused it around the time of the save so that I could grab the video with the ship stopped.

Also note that I don't have the ship as the view most of the time. I typically just have it remote view set to Aquilo zoomed out while it runs.

After a day or two you should notice the fog stutters. I wish it could be repro'd faster. It *might* repro faster if you just uncap game speed, but I have not tried that here yet.

*edit* I noticed that the two stationary platforms do not have the issue, and the fog scrolls smoothly. It is just the two mobile platforms which accumulate the fog stutter effect over time on their respective surfaces. With ~2.5 days on this save so far, I stopped the other platform mid-route (closer to the source planet), and the fog started dancing around:

2026-03-06 00-25-32.mp4

(2.76 MiB) Downloaded 1 time

[posila]

Hello,
Rseding, I don't remember exact details, but there is a non-game state variable somewhere (probably on SpacePlatform, or Hub), which accumulates space background offset as platform travels. Since the plaform visually always travels up, the offset always just grows. It's not saved in order to hide floating point precision issues by it starting from 0 everytime a save is loaded. It seems running the game for a week was enough for FP precision issues to make themselves show. As for repro... you can try to initialize that variable to some large number instead of 0.