Rendering artifact I can't identify.

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ChopBlock223
Posts: 80
Joined: Tue Apr 02, 2019 3:19 pm
Operating System Version (Optional): Windows 10 with extensive trimming and regedits.
Graphics Processor: nVidia (Modern GZDoom)

Rendering artifact I can't identify.

Post by ChopBlock223 »

I very occasionally experience this graphic glitch which I'm not sure of what it is. I am not particularly tech savvy, so I can't say. What I can say is that it did not happen on older versions of GzDoom, and it doesn't seem to happen very often, just every now and then. It does not happen with GzDoombuilder.
https://i.imgur.com/vesetZJ.png

There's no stuttering or other visual artifacts following, in fact everything around the affected areas is fine and nothing else about the game will be abnormal. It also does not seem to correspond at all to level data, it ignores linedefs and sectors, and the linedefs and sectors appear to be perfectly normal if examined, nothing weird with the nodes or visplanes from what I can tell, and these things are always fine in PrBoom+.

I'd be terrified of it being a hardware problem, but the fact I don't experience this with anything else makes me think that it isn't. It seems to just happen on some levels, and I'm not sure why, but it would seem to be something on GzDoom's end. Seems to happen with or without gameplay mods.

Level I was playing:
https://www.doomworld.com/idgames/level ... g-i/gothic

Mod I was playing:
https://www.doomworld.com/idgames/combos/2048guns

My autoload.
[doom.Autoload]
Path=C:/Spel/Doom/gzdoom-bin-3-1-0a-x64/steve_flashlight_2018.02.12.pk7
Path=C:/Spel/Doom/gzdoom-bin-3-1-0a-x64/TiltPlusPlusv1.5.pk3
Path=C:/Spel/Doom/gzdoom-bin-3-1-0a-x64/SBrightmaps.pk3
Path=C:/Spel/Doom/gzdoom-bin-3-1-0a-x64/gzd_brightmaps141.pk3
Path=C:/Spel/Doom/gzdoom-bin-3-1-0a-x64/DOOMTESTB.wad //modified test level I use for development
Path=C:/Spel/Doom/gzdoom-bin-3-1-0a-x64/PunkSuicide.wad //player skin
Path=C:/Spel/Doom/gzdoom-bin-3-1-0a-x64/mXhairs_2.1.pk3 //was not loaded at the time of this screenshot
Path=C:/Spel/Doom/gzdoom-bin-3-1-0a-x64/precise-crosshair-v1.4.1.pk3 //ditto

[doom.id.Autoload]
Path=C:/Spel/Doom/gzdoom-bin-3-1-0a-x64/D1SPFX18.wad
Path=C:/Spel/Doom/gzdoom-bin-3-1-0a-x64/D1DEHFIX.DEH
Path=C:/Spel/Doom/gzdoom-bin-3-1-0a-x64/SBrightmaps.pk3
Path=C:/Spel/Doom/gzdoom-bin-3-1-0a-x64/gzd_brightmaps141.pk3

[doom.id.doom2.Autoload]
Path=C:/Spel/Doom/gzdoom-bin-3-1-0a-x64/D2SPFX18.wad
Path=C:/Spel/Doom/gzdoom-bin-3-1-0a-x64/D2DEHFIX.DEH
Path=C:/Spel/Doom/gzdoom-bin-3-1-0a-x64/SBrightmaps.pk3
Path=C:/Spel/Doom/gzdoom-bin-3-1-0a-x64/gzd_brightmaps141.pk3

[doom.id.doom2.plutonia.Autoload]
Path=C:/Spel/Doom/gzdoom-bin-3-1-0a-x64/D2SPFX18.wad
Path=C:/Spel/Doom/gzdoom-bin-3-1-0a-x64/D2DEHFIX.DEH
Path=C:/Spel/Doom/gzdoom-bin-3-1-0a-x64/SBrightmaps.pk3
Path=C:/Spel/Doom/gzdoom-bin-3-1-0a-x64/SBX_PLUT.pk3
Path=C:/Spel/Doom/gzdoom-bin-3-1-0a-x64/gzd_brightmaps141.pk3

[doom.id.doom2.tnt.Autoload]
Path=C:/Spel/Doom/gzdoom-bin-3-1-0a-x64/D2SPFX18.wad
Path=C:/Spel/Doom/gzdoom-bin-3-1-0a-x64/D2DEHFIX.DEH
Path=C:/Spel/Doom/gzdoom-bin-3-1-0a-x64/SBrightmaps.pk3
Path=C:/Spel/Doom/gzdoom-bin-3-1-0a-x64/SBX_TNT.pk3
Path=C:/Spel/Doom/gzdoom-bin-3-1-0a-x64/gzd_brightmaps141.pk3

[doom.id.doom1.Autoload]
Path=C:/Spel/Doom/gzdoom-bin-3-1-0a-x64/D1SPFX18.wad
Path=C:/Spel/Doom/gzdoom-bin-3-1-0a-x64/D1DEHFIX.DEH
Path=C:/Spel/Doom/gzdoom-bin-3-1-0a-x64/SBrightmaps.pk3
Path=C:/Spel/Doom/gzdoom-bin-3-1-0a-x64/gzd_brightmaps141.pk3

[doom.id.doom1.registered.Autoload]
Path=C:/Spel/Doom/gzdoom-bin-3-1-0a-x64/D1SPFX18.wad
Path=C:/Spel/Doom/gzdoom-bin-3-1-0a-x64/D1DEHFIX.DEH
Path=C:/Spel/Doom/gzdoom-bin-3-1-0a-x64/SBrightmaps.pk3
Path=C:/Spel/Doom/gzdoom-bin-3-1-0a-x64/gzd_brightmaps141.pk3

[doom.id.doom1.ultimate.Autoload]
Path=C:/Spel/Doom/gzdoom-bin-3-1-0a-x64/D1SPFX18.wad
Path=C:/Spel/Doom/gzdoom-bin-3-1-0a-x64/D1DEHFIX.DEH
Path=C:/Spel/Doom/gzdoom-bin-3-1-0a-x64/SBrightmaps.pk3
Path=C:/Spel/Doom/gzdoom-bin-3-1-0a-x64/gzd_brightmaps141.pk3
The folder still says 3.1.0, because I installed GzDoom 4.5.0 separately, as I wasn't sure if it would work or not (but other than this one thing, which may or may not be 4.5.0's fault, it actually works better overall and I like the new options).
I just dump whatever .wads I download, play, or work on in the old folder, because I'm a computer slob and don't organize that well. Keeps the new folder more tidy anyway.

I didn't see any mention of anything like this elsewhere, but I apologize if this is something that hasn't been reported (I don't know what I'm looking at, mind). I'm not sure if there's further information I can provide.
User avatar
phantombeta
Posts: 2117
Joined: Thu May 02, 2013 1:27 am
Operating System Version (Optional): Windows 10
Graphics Processor: nVidia with Vulkan support
Location: Brazil

Re: Rendering artifact I can't identify.

Post by phantombeta »

Are you using an Intel GPU? That exact issue is something I've noticed when I used an Intel GPU, and at least a few other people have too. It seems to be specific to Intel GPUs, so it's probably an issue on Intel's end.
User avatar
ChopBlock223
Posts: 80
Joined: Tue Apr 02, 2019 3:19 pm
Operating System Version (Optional): Windows 10 with extensive trimming and regedits.
Graphics Processor: nVidia (Modern GZDoom)

Re: Rendering artifact I can't identify.

Post by ChopBlock223 »

I realize actually that my example image isn't great, so I went back to the level and took a bunch of screenshots in fullbright, these screenshots all kinda show the flickering (I think putting them into a .gif would make it too big or remove too much useful definition from compression, also I don't know how to record video).
Here's multiple images demonstrating the warping (which it does very rapidly):
https://imgur.com/a/qngZN5n

The last image shows the spot from a different angle, where this phenomenon doesn't happen.

My laptop does in fact use an Intel GPU.
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KynikossDragonn
Posts: 272
Joined: Sat Dec 12, 2020 10:59 am
Preferred Pronouns: He/Him
Operating System Version (Optional): Void Linux
Graphics Processor: Intel (Modern GZDoom)
Location: Independence, KS, USA

Re: Rendering artifact I can't identify.

Post by KynikossDragonn »

Yeah, on Vulkan and OpenGL there are certain polys in maps that will suddenly go berzerk and stretch and contort themselves nonsensically in random patterns depending on where your viewport is and how it's rotated.

Even Kinsie's test map produces this problem if you go up the really tall elevator, stand near the edge and look down, a single poly completely messes up that badly like in the screenshots.

It would be worth reporting this to whatever driver vendor, if you're a Linux user this should be reported to the Mesa bugtracker if possible.
User avatar
ChopBlock223
Posts: 80
Joined: Tue Apr 02, 2019 3:19 pm
Operating System Version (Optional): Windows 10 with extensive trimming and regedits.
Graphics Processor: nVidia (Modern GZDoom)

Re: Rendering artifact I can't identify.

Post by ChopBlock223 »

Interesting, I'm glad it's a known problem and not a sign that my GPU is imploding or anything. If I'm understanding the previous post right, this is an issue typical of the Intel GPUs, correct? Further, would Nvidia GPUs be best suited for Vulkan? I have a vague understanding that it tends to work better with their hardware, and that Vulkan tends to have somewhat better performance with GzDoom.

These artifacts aren't a massive problem, as they appear rather seldom, and they have yet to cause any kind of performance or gameplay problems, so I can tolerate visits by MissingNo. for the time being, though I should be making plans for a newer computer sometime in the not that distant future.

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