Texture dialation - Adjacent faces margin type dialates pixels inside uv island #119393

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Marko Tatalovic · 2024-03-12T18:57:36+01:00

Marko Tatalovic commented

2024-03-12 18:57:36 +01:00

System Information
Operating system: Windows 10
Graphics card: GeForce 2080 TI

Blender Version
Broken: (example: 4.0.2, 9be62e85b7, master, 2023-12-05, as found on the splash screen)
Worked: (3.6.8)

Short description of error
Not sure if new behaviour is inteded or a bug:

Baking with 'Adjacent faces' as the margin type in version 4.0.2 dialates pixels inside the uv shell.

Exact steps for others to reproduce the error

Open provided file in Blender 3.6
Select "selected" object then select "active" object
Press Bake
Open provided file in Blender 4.0.2
Select "selected" object then select "active" object
Press Bake!
See the difference

B 4.0.2:

B 3.6.8:

**System Information** Operating system: Windows 10 Graphics card: GeForce 2080 TI **Blender Version** Broken: (example: 4.0.2, 9be62e85b727, master, 2023-12-05, as found on the splash screen) Worked: (3.6.8) **Short description of error** Not sure if new behaviour is inteded or a bug: Baking with 'Adjacent faces' as the margin type in version 4.0.2 dialates pixels inside the uv shell. **Exact steps for others to reproduce the error** 1. Open provided file in Blender 3.6 2. Select "selected" object then select "active" object 3. Press Bake 4. Open provided file in Blender 4.0.2 5. Select "selected" object then select "active" object 6. Press Bake! 7. See the difference B 4.0.2: ![image](/attachments/77f9c029-3b17-4e38-9ef7-fbe919008113) B 3.6.8: ![image](/attachments/5e75363a-6aa6-40ed-aae8-5c89fd94394e)

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Marko Tatalovic added the

labels 2024-03-12 18:57:37 +01:00

Marko Tatalovic changed title from ~~Texture dialation - Adjacent faces margin type has dialates pixels inside uv island~~ to Texture dialation - Adjacent faces margin type dialates pixels inside uv island

2024-03-12 18:59:21 +01:00

Pratik Borhade commented

2024-03-13 10:41:07 +01:00

Hi, thanks for the report. Can confirm.
Broke between 7be0d1481c67 - 827baed610b8
@lichtwerk , can you help bisecting? 😅

Hi, thanks for the report. Can confirm. Broke between `7be0d1481c67 - 827baed610b8` @lichtwerk , can you help bisecting? 😅

Pratik Borhade added

and removed

labels 2024-03-13 10:50:57 +01:00

Philipp Oeser commented

2024-03-13 12:16:51 +01:00

Can check later (currently need to fix a backport first)

Brecht Van Lommel commented

2024-03-13 12:36:48 +01:00

It was an intentional change in #109500 to fix another bug.

Is the new behavior a problem?

It was an intentional change in #109500 to fix another bug. Is the new behavior a problem?

Marko Tatalovic commented

2024-03-13 13:00:41 +01:00

Hello,

We are developing automatisation tools for baking LODs at our company.

We were relying on the behaviour from 3.6.8 to detect where are the holes in the higher LODs (for windows and doors) by relying on the ray missing, which is not possible in newer versions. I would say for potential ray misses on the seams/hard edges new behaviour might be better.

For fixing ray misses on the seams we do another bake with smooth cage, and blend it in with the first bake.

Right now for the 4.0.2 + we had to implement our own padding in python. We do fill in windows and doors with non alpha color so padding doesn't affect those areas.

I think it would be useful feature to have option for dialation to skip transparent pixels inside the uvshell.

In 3.6.8 Adjacent faces margin type did dialate alpha pixels on the uv border which is not ideal, but that can be easily fixed by doing second bake with smooth cage as I mentioned above.

Hello, We are developing automatisation tools for baking LODs at our company. We were relying on the behaviour from 3.6.8 to detect where are the holes in the higher LODs (for windows and doors) by relying on the ray missing, which is not possible in newer versions. I would say for potential ray misses on the seams/hard edges new behaviour might be better. For fixing ray misses on the seams we do another bake with smooth cage, and blend it in with the first bake. Right now for the 4.0.2 + we had to implement our own padding in python. We do fill in windows and doors with non alpha color so padding doesn't affect those areas. I think it would be useful feature to have option for dialation to skip transparent pixels inside the uvshell. In 3.6.8 Adjacent faces margin type did dialate alpha pixels on the uv border which is not ideal, but that can be easily fixed by doing second bake with smooth cage as I mentioned above.

Brecht Van Lommel commented

2024-03-13 19:10:01 +01:00

@Baardaap I guess we can add an option for this?

Maybe the right default behavior is even the old one. It's probably less common to bake to multiple texture maps with adjacent islands, than to bake incrementally to a single texture map where you don't want it to overwrite other UV islands.

@Baardaap I guess we can add an option for this? Maybe the right default behavior is even the old one. It's probably less common to bake to multiple texture maps with adjacent islands, than to bake incrementally to a single texture map where you don't want it to overwrite other UV islands.

Martijn Versteegh commented

2024-03-13 22:00:03 +01:00

I guess I should try to make it so that only edges of which the adjacent polygon is in the current bake as well get a generated border, while edges where the border is not an outside border of the uv map shoudl be ignored.

I'll try to find some time to look into it.

I guess I should try to make it so that only edges of which the adjacent polygon is in the current bake as well get a generated border, while edges where the border is not an outside border of the uv map shoudl be ignored. I'll try to find some time to look into it.

Brecht Van Lommel added this to the 4.2 LTS milestone 2024-03-15 14:15:38 +01:00

Martijn Versteegh commented

2024-04-04 22:08:12 +02:00

I did start to look into it a bit.

@Fuxna : Am I correct in understanding that the old 'extend' method has exactly the same problem?

It's not totally trivial to fix in a clean way, and I disagree with @brecht that the 4.0.2 behaviour could be the correct one as
a) That did not match the behaviour of the 'extend' method.
b) That could mess up edges of the UV map that were not part of the bake as well, along the outer edge of the UV map for polygons that were not part of the bake.

To fix this I'd need to actively suppress generating a border along edges which border polygons not part of the bake. Which could be done for the 'Adjacent Faces', but would be hard for the 'Extend' method as that is purely an image filter and has no info about the polygons. I also use 'Extend' as a in 'Adjacent Faces' to fill some holes not filled by the adjacent faces algorithm, so that's sl;ightly problematic (though apparently it was no problem in 4.0.2? I don't fully understand that yet, need to investigate that a bit more).

I did start to look into it a bit. @Fuxna : Am I correct in understanding that the old 'extend' method has exactly the same problem? It's not totally trivial to fix in a clean way, and I disagree with @brecht that the 4.0.2 behaviour could be the correct one as a) That did not match the behaviour of the 'extend' method. b) That could mess up edges of the UV map that were not part of the bake as well, along the outer edge of the UV map for polygons that were not part of the bake. To fix this I'd need to actively suppress generating a border along edges which border polygons not part of the bake. Which could be done for the 'Adjacent Faces', but would be hard for the 'Extend' method as that is purely an image filter and has no info about the polygons. I also use 'Extend' as a in 'Adjacent Faces' to fill some holes not filled by the adjacent faces algorithm, so that's sl;ightly problematic (though apparently it was no problem in 4.0.2? I don't fully understand that yet, need to investigate that a bit more).

Marko Tatalovic commented

2024-04-08 18:41:26 +02:00

@Fuxna : Am I correct in understanding that the old 'extend' method has exactly the same problem?

@Baardaap Yes it pads all alpha pixels. Also I need to update how it behaved before (for the 'ADJACENT'). I wrongly thought that there is no padding for the windows and doors. but it actually does some padding altho it doesn't fill the hole all the way.

in the test file its also there but only few pixels, so that's why me ( and I guess all of uss missed it).

Right now we moved to using compositor nodes to solve our problem. Not sure what to do about this one.

> @Fuxna : Am I correct in understanding that the old 'extend' method has exactly the same problem? @Baardaap Yes it pads all alpha pixels. Also I need to update how it behaved before (for the 'ADJACENT'). I wrongly thought that there is no padding for the windows and doors. but it actually does some padding altho it doesn't fill the hole all the way. ![image](/attachments/1e0fc07a-448d-46be-8b24-4c452c7e5bc1) ![image](/attachments/c4a8dba4-2d81-4b6a-9085-cdb010940209) in the test file its also there but only few pixels, so that's why me ( and I guess all of uss missed it). Right now we moved to using compositor nodes to solve our problem. Not sure what to do about this one.

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Marko Tatalovic closed this issue

2024-04-08 18:41:30 +02:00

Blender Bot added

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labels 2024-04-08 18:41:33 +02:00

Marko Tatalovic commented

2024-04-08 18:42:32 +02:00

I am an idiot I did the comment and close again... Move the button somewhere else :D

Marko Tatalovic reopened this issue

2024-04-08 18:42:35 +02:00

Blender Bot added

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labels 2024-04-08 18:42:37 +02:00

Philipp Oeser added

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labels 2024-04-09 09:41:11 +02:00

Martijn Versteegh commented

2024-05-04 13:22:55 +02:00

I have been playing a bit with possible fixes, but all things I tried up to now I wasn't really satisfied with, because they all involved creating a full copy of the mask and also involved quite a bi more lookup per pixel.

Since I currently don't have too much time for blender coding I'm afraid I won't be able to get something in for this before 4.2.

Also I'm not really sure this qualifies as a bug per-se, though it would of course be a nice option to have. The original 'extend' border generation did not support this either, and the way it mostly worked out in 3.6 was a side effect of an actual bug (and I think it wasn't really guaranteed to work either, as it would create borders around the outside edges of the complete UV map, which will still generate unwanted borders in place you don't want them.

I will try to get something working for post 4.2

I have been playing a bit with possible fixes, but all things I tried up to now I wasn't really satisfied with, because they all involved creating a full copy of the mask and also involved quite a bi more lookup per pixel. Since I currently don't have too much time for blender coding I'm afraid I won't be able to get something in for this before 4.2. Also I'm not really sure this qualifies as a bug per-se, though it would of course be a nice option to have. The original 'extend' border generation did not support this either, and the way it mostly worked out in 3.6 was a side effect of an actual bug (and I think it wasn't really guaranteed to work either, as it would create borders around the outside edges of the complete UV map, which will still generate unwanted borders in place you don't want them. I will try to get something working for post 4.2

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Texture dialation - Adjacent faces margin type dialates pixels inside uv island #119393