DirectX 5 graphical glitch

[foxtacles]

No idea when it was introduced, but wasn't there in the beginning:

(notice the line in the middle of the screen that appears sometimes)

Screen.Recording.2025-08-21.113747.mp4

[AJenbo]

We had a very similar issue at one point in the software renderer where it didn't handle rounding of very small triangles correctly:

#280 (comment)

Since your appear to be using a software renderer in the video I would think that it's likely that they have the very same issue in there but just isn't something you have noticed much previously, or maybe it's been introduced with some windows update or similar change.