Sonic Adventure 2 [NTSC] having odd flickering borders at specific part of Egg Quarters

[TailsGuy]

Platform / OS / Hardware: Windows 11

Github hash: a21b79cf

Hardware: AMD Ryzen 7 5700X, EVGA NVIDIA GeForce RTX 3070 FTW3

Description of the Issue

So, there's an odd issue in Egg Quarters in Sonic Adventure 2 (NTSC), (Real BIOS, Automatically sets language to Japanese in game) where at this specific spot in the level, there are various borders popping in an out rapidly. I've put some photos.

Debugging Steps Tested

• Boot SA2 Normally, and go into the Stage Select, Choose Egg Quarters, a Rouge stage near the pyramid in the stage select.
• You're not far at all, you're in the red room and walk left into the door way which leads into the iron room. You'll notice the flickering by the door way.

Logs Gathered

These are logs from a second run with logs enabled.

flycast.log

Screenshots

[flyinghead]

I haven't been able to reproduce the issue on nvidia gtx 1080, tried opengl and vulkan.

Can you upgrade to the latest flycast version and retest? What are your graphics settings?

[TailsGuy]

I've upgraded, and it's still there.

Everything's on default except the resolution, and even on native it's still there. I'm on the latest graphics driver, and on DX9.

Per-Triangle rendering and Per-Strip are glitched here btw.

[flyinghead]

Did you try other graphics api? DX11 is now the default on windows and, based on the crash reports I get, the DX9 nvidia drivers are pretty bad. Vulkan is worth a try too.

[TailsGuy]

Oh, sure, let me do that right now, sorry!

[TailsGuy]

It works with DX11 and Vulkan!