[BUG]: Gran Turismo 4 Texture Flickering

[blisstik]

Describe the Bug

The car models have triangular texture flickering issue. I am not sure if this is z-fighting. I am using the same per-game config on original XBSX2 which does not have this issue.

Reproduction Steps

Go on a track and change to hood or behind the car view.

Expected Behavior

No response

PCSX2 Revision

Initial release by SirMangler

Operating System

Linux (64bit) - Specify distro below

If Linux - Specify Distro

Xbox Series S

CPU

Stock

GPU

Stock

GS Settings

No response

Emulation Settings

No response

GS Window Screenshots

No response

Logs & Dumps

No response

[SirMangler]

Can you confirm if the latest PCSX2 nightlys have this issue? This kind of issue isn't necessarily one we can fix. It may also be a settings related problem.

[TheRhysWyrill]

This issue is related to Accurate DATE which was removed from PCSX2 a long time ago, fairly certain this does not occur on Vulkan, probably a D3D exclusive issue.

[Jeenvries]

Known Issues Missing/flickering textures Status: Active Type: Minor Description: Missing ground textures and/or textures in the distance flicker. Workaround: Go to Config -> Video (GS) -> Plugin Settings, and set Renderer to any of the "(Software)" options. Then Make sure the Mipmapping option is checked at Software Mode Settings.

Looks like this is not xbsx2.0 specific. Did you try any of these settings

[blisstik]

The issue does not occur using Software renderer.

On a Macbook Pro M1, the issue does not exist in Hardware renderer mode

Is there a way to patch the issue? I've read other games have this issue as well such as Driver 3 (comments from Discord).

[GABO1423]

This issue is related to Accurate DATE which was removed from PCSX2 a long time ago, fairly certain this does not occur on Vulkan, probably a D3D exclusive issue.

FWIW, the issue is not present on the latest AetherSX2 build, although this issue was present there in past builds. Seems to be a UWP issue since it also can't be replicated on PCSX2 proper (even on Windows).

[mansoor909]

The Gran Turismo 3 and 4 texture corruption fix was removed due to the newest PCSX2 update removed the "Accurate Destination Alpha Test" option that is needed to fix the issue. We'll have to wait for that option to return in order to fix the texture issue in these Gran Turismo games. If you still have an older version of XBSX2 the "Accurate Destination Alpha Test" option should still be available for you to turn it off and should fix the texture glitch.

[blisstik]

I’m wondering the feasibility of backporting it?

https://github.com/PCSX2/pcsx2/pull/7003/commits

[GABO1423]

I managed to restore the setting in the PR above, here's a sneak peak of the results:

AccurateDATE enabled (current behavior):

AccurateDATE disabled:

[GABO1423]

@blisstik Here's a test build, can you verify if #4 is also fixed with the setting off?

XBSX2.0.zip

EDIT: You shouldn't import any settings btw, and it will not overwrite your current installation

[mansoor909]

Version tested 1-Gran Turismo 3 2-Gran Turismo 4 3-NBA Street Vol. 2 the problem has been resolved Texture Flickering

*Note NBA Street Vol. 2 works at half speed after repair

[GABO1423]

Version tested 1-Gran Turismo 3 2-Gran Turismo 4 3-NBA Street Vol. 2 the problem has been resolved Texture Flickering

*Note NBA Street Vol. 2 works at half speed after repair

All of these running at default settings? (Minus the new setting being disabled of course)

[mansoor909]

On my 4k settings

NBA Street Vol. 2

When AccurateDATE is disabled GPU is used:100% and FPS: 21

When AccurateDATE is enabled GPU Used:99.2% and FPS:73

[GABO1423]

On my 4k settings

NBA Street Vol. 2

When AccurateDATE is disabled GPU is used:100% and FPS: 21

When AccurateDATE is enabled GPU Used:99.2% and FPS:73

4K is definitely not default settings (which is what I asked for) and definitely adds a performance hit since it's very much over the top. There's a reason 1080p is the default. EDIT: Misread, discard point 2

[mansoor909]

Tested at 4k resolution The difference appears when AccurateDATE is disabled or enabled I will re-test the default settings

[mansoor909]

default settings

When AccurateDATE is disabled GPU is used:33.2% and FPS: 59.94

When AccurateDATE is enabled GPU is used:21.8% and FPS: 59.94

[GABO1423]

default settings

When AccurateDATE is disabled GPU is used:33.2% and FPS: 59.94

When AccurateDATE is enabled GPU is used:21.8% and FPS: 59.94

This confirms the huge performance disparity was because of your settings.