Flickering in texture

I am rendering some boxes with 32x anti alias and in 32 bit float,
with some textures applied in PBR material with bump maps,
the thing is, when adding the bump maps, and outputting it to video and also watching it in real time,
there is this kind of flickering in the texture, very odd,
why is this happening and how can it be prevented?

what factors can produce flickering in the textures applied to SOPs?
I have changed things in lights etc but it doesnt go away mmm
thank you :slight_smile:

I am trying all sort of things, but this is a real big problem for me. I am using 8K textures, very high res, I am putting render node in 32x antialias, y using 32bit float as output, etc,
but I keep seeing this weird flickering in parts of the textures I put in the objects

I see a difference when I change 32x antialias back to 4x, there is more flickering with 4x than with 32x, but there is still very visible flickering with 32x that is the maximum

there must be a way to get rid of this flickering, help please

The issue is very easy to see with this very simple example.
In my work I need to apply 3 kinds of maps, the base color map, a bump map and a roughness map, in a PBR material. With only the base color map it is harder to see the flickering but if you look carefully it is still there. When adding the other two maps, the flickering becomes super clear.
I notice things like:

  • Flickering is more with 4x antialias than with 32x but with 32x is still clearly there
  • Flickering is more in 3840x2160 resolution than in 1280x720 resolution but I need to do my project in 3840x2160. My equipment by the way uses an RTX 3090 card from Nvidia and its a powerful machine, no issues with the machine
  • If there is zero movement, if nothing moves, then there is no flickering. But of course I always need movement in all my scenes :slight_smile:

Could you please show me what can be done in this simple example so that such a box, having those 3 maps applied, a base color, a bump and a roughness, in a PBR material, so that it doesnt do that flickering? thank you so very much

flickeringissue.11.toe (5.6 KB)

Have you played around with the mipmapping and anisotropic filter setting? I didn’t even know they existed until recently:

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@matijaerceg I never did, thank you for discovering them for me, do you think they may help with the flickering? I will change their settings to see if anything changes thank you :slight_smile:

@matijaerceg I just tried those 2 parameters but unfortunately they dont solve the flickering, same issue yeah

@matijaerceg the bump map definitely makes the flickering so much worse, if you take the parameter Texture Coord in those sets of parameters you showed me and you set it to some other value, the bump dissappears and the flickering also, both. Once you set it to the proper layer, the bump comes back and the flickering as well massively. There must be something that can be done to have the bump without the flickering

@matijaerceg
interestingly I see more people online talking about bump maps + flickering, like for example:

there must be some trick in TD so solve the issue, in the style of what they say in that link but adapted to TD, lets see if any TD gurus can tell us

@matijaerceg
the problem only happens when there is movement. So as this other post indicates, the problem seems to be related to the displacement caused by the bump map being recalculated every time things move in relation to certain coordinates when it should be done in relation to different coordinates, I wonder whats the way to fix this in TD, gurus please tell us :slight_smile:

can you lock the tops since they’re missing when i try to open your file

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@matijaerceg yes but Im not sure actually how to do that, you mean to include them in the file right? how do I do that?

https://docs.derivative.ca/Lock_Flag

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@matijaerceg
yes im trying to zip it, this doesnt let me upload more than 4mb and it occupies 12mb, im trying to compress it, one minute

@matijaerceg
managed to do it as a zip, with the lock it didnt go below 4mb, but I zipped them externally, so there you have the base and the bump maps, just load them into the two tops and you have the same I have, and this is a great example to test the flickering yeah :wink:
export.zip (1.8 MB)

can you record and upload either a gif or zipped short video at 60 fps (or30) of the flicker?
I’m looking at your export.zip but seeing no obvious source of flicker.

Flickering can mean many different things, and can even be hardware or setup related.

@lucasm
its difficult to capture this in an mp4 but anyway this is an example,
in here i have replaced textures with even higher resolution ones,
despite the issues with the mp4, the problem is clear in the faces top right and bottom right
flickersee1.zip (2.6 MB)
flickersee2.zip (1.8 MB)

the problem is caused by the recalculation when movement happens of the bump map interacting with movement and lights etc,
in some cases is more apparent and in others less, if you put roughness to less than 1 in the PBR then it becomes way more apparent, etc,

but from that to not seeing it at all… I wish…
I really wish that this may be a setup problem in my machine, I hope so, that would be awesome :slight_smile:

although I would be surprised, as I have read online about other people having similar problems with bump maps + movement in other softwares, and finding solutions for them but solutions which I dont know how would be done in TD

my machine has an RTX 3090 of nvidia and otherwise is a powerful standard windows machine

all tips super welcome :slight_smile:

Thanks for the uploads! this helps a lot. If you can somehow send the full high res example you had in that video that would be a plus, but I don’t think that’s necessary as I believe I see the problem now.


The flickering does feel like it’s related to the normal as you said.

Taking a look at your normal map, it looks pretty odd to me. some areas look “grey” which is not something I ever see in tangent space normals.
image

Here’s an example of some other random pbr texture’s normal map:


One thing you can do is to open the viewer for your normal map, and hit “v” to view as points. Here’s what your normal map looks like:
noisyBlobUVS

Here’s what a typical normal map looks like - like a hollowed out half sphere:
sphericalBlobUVS

The difference between the two becomes more obvious when viewing the pixels as positions in space rather than colors on a flat image.

I think you need to double check your export of the normal map, wherever it came from.


Also, for your material, [almost] always use mipmap linear, it performs WAY better for objects at a distance, as it samples from lower mip levels when objects are far away which the gpu can do more efficiently. setting to nearest will give you really blocky pixels, and nearest or linear will not use mip levels, and cost the same regardless of how close the texture is.

There are reasons and times to use both of those, but for you I think you want mip map linear.

As far as Anisotropic Filtering, it is very expensive on the rendering but it really improves the look of the texture when the polygon is facing away from the camera.

If all of your geometries are more or less facing the camera straight on then turn that off, it’s not helping much.

If you have all your samplers at 16x anisotropic and 32x antialias your render top will bring even your 3090 to it’s knees pretty quickly :sweat_smile:

One thing you can do is lower your render top’s antialias to 8 or 16, and use an antialias TOP near the end of your render to smooth things out a bit more in screen space.

the render TOP’s anti alias actually renders more pixels, and averages them to the final pixel, so 4x means literally 4x the number of pixels being calculated! so very expensive to increase that.

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@lucasm wow wow wow, what an awesome response, thank you so much Lucas! :smiley:
so I downloaded that normal map from a website where you can download free models and textures, it came prepackaged with roughtness, base maps, etc for a metal texture. Interesting what you say, that maybe they just provided a normal map that is not in a good state. Do you have btw advice of where I can find good quality and decent texture maps for metals with rust, iron bars, things like that?

regarding the end of your message, the antialias top, very interesting, but what is the difference between setting the render node in 16 o 32 antialias vs using an antialias top as an extra (before or after the render node?)

ahh just as you posted that I had updated my above post - basically render top anti alias renders more pixels, where as the antialias TOP actually uses some logic to selectively smooth/filter/blur various nearby pixels together to give a more anti aliased look.

doing it as a TOP down stream will never look as good as doing it in the render top, but it will be more performant.

Sometimes doing a bit of both can make for good results.


Out of curiosity, do you have a link to the site you got the pbr materials from? I am curious.

sharetextures.com (previously cc0 textures) is a good one
FreePBR is also another nice resource
textures.com is massive and nice.

For much more official / high quality adobe has their substance community assets. Though not sure what the license is for them, so check first if you are doing commercial work!

@lucasm great points indeed! :slight_smile:
I have the Adobe creative suite entire commercial licence, however unfortunately it doesnt include the substance materials, they have that separately, a pity indeed;
I downloaded a bunch of free textures today, just looked at the files but I cannot see from which website they came unfortunately its not in their names ; im going to look for new ones in the websites you mention to try new normal bump maps and confirm that the problem doesnt happen with good bump maps, will try :slight_smile: