Serious Bug on Texturing

[ian1]

Hello Blender friends :),
It’s not often that I ask a question on the web, but here I’m really stumped.

I think I noticed a serious bug in blender’s texturing.

After several experiments under multiple versions of blender, several OS (windows/linux), GPUs (Radeon/Nvidia) and PCs, the painting generates artifacts.
It generates dots (pixels) on the drawn areas.

The more you increase the resolution (4K,8K,16K), the more visible and very disturbing it is.
I really think I have tried everything to fix this problem without success.

To try, start by subdividing a cube with 3 or 4 iterations and create a 16K texture.
Start painting on it… You will see dots and lines.

… Any idea ?

Thanks for reading.

Sincerely,

ian1

[stray]

Interesting.
Can’t offer anything useful, but I too have encountered similar behavior. Usually just a few pixels (on 2k textures). After changing zoom and/or view angle I could paint over it.

What I haven’t noticed before is that it seems to occur only on diagonal “edges” inside quads
edit. huh, wrong observation: it occurs at edges that have 45 degree angle in UV map…

[ian1]

Exactly
At the moment I am stuck, I hope someone will find the solution.

Thanks for your comment.

[ian1]

I’ve noticed that this bug affects all resolutions actually.

You can try on a 1K Texture the fill option.
You’ll notice lines and dots around the mesh.

Still no ideas? ^^’

Even the “Quick Edit” (Edit a snapshot of the 3D Viewport in an external image editor.) doesn’t fix this problem.

If any of you know a Developer, please pass the info on
Thanks for reading.

Sincerely,

ian1

[humanartist]

A solution I have for the lines showing up is to scale down the UVMapping so there is blank boarder around the UVMap Islands. Then paint the model using a bleed of at least 8px.

[stray]

That’s just the thing, bleed doesn’t affect this issue at all. Also it happens “inside” the island

[ian1]

StrayBillie answered for me.
Thanks for your comments friends.

[RSEhlers]

Hmmm…that is strange as I have never seen this on any version…and I have an older AMD processor 6-core with Nvidia 2070 RTX…and using a 32" HDMI TV to view., (I’m old)

[ian1]

okay, really interesting…

Are you sure ? no dots ?
My CPU is a Ryzen 3900x
What is your CPU please ?
at intel have the same problem ?

I specify, it’s the polypainting that is buggy, not the texture editor.

I hope I won’t have to change my PC…

Thanks for your help.

[RSEhlers]

it is over 6 years old…started out as
Cybertron PC Hellion (Blue) TGM1213J Gaming PC (3.5 GHz AMD FX-6300 6-Core, 2GB GeForce GT740, 16GB DDR3 1600MHz, 1TB HDD, WiFi, Windows 10 Home 64-Bit
Updated Ram and GPU

[ian1]

It may be a bug related to Ryzen Cpus…
It doesn’t help me much but I am reassured to see that this problem is not common to all.

Thanks for the info friend.

[RobWu (Rob)]

If you think it’s a bug, please report it.
The devs normally don’t hang out here, and if you make a proper report of it with all steps involved you will get more traction.
Also, be sure you can reproduce it every time.

[ian1]

Hi,
Indeed, this is exactly what I was thinking of doing tomorrow on the Blender github.
Did you also have another link to propose ?

I just experimented the bug on a friend’s laptop.
Old intel CPU and same bug.
I don’t think the CPU is the cause.
I think this bug concerns everyone. Really

Hopefully the devs will fix this bug…

Thanks for your comments friends

[RobWu (Rob)]

Just use the bug report option in Blender, or -if you have a account there- post it on the blender devtalk forum.

rob

[ian1]

I followed your advice.

In the meantime, I’m stuck.
If any of you have the same problem please follow rob’s advice as well as posting it here.

Thank you all.

Sincerely
ian1