Regression: EEVEE Color banding in viewport image render #113266

New Issue

Alex Mehler · 2023-10-05T00:33:30+02:00

Alex Mehler commented

2023-10-05 00:33:30 +02:00

System Information
Operating system: win11
Graphics card: rtx3060

Blender Version
any newer version 4.0 /4.1
Worked: 3.6

Short description of error
When rendering with viewport rendering, the output has heavy banding. Must be some conversion error, as you can see the screenshot of the viewport looks just fine, as do the textures in every other programs.

this problem persists , no matter if viewport compositing is enabled or not.
the whole image looks like a bad gif with reduced colors.

Step to Reproduce

Open attached file
Switch to viewport render
View -> Viewport Render Image

banding_demo.blend

viewport - looks fine	viewport render - banding

Original report

Viewport screenshot - looks absolutely fine ![grafik](/attachments/ee9c7ae8-d7cd-4977-a36e-1b06d1daf730)

normal render - looks absolutely fine

viewport render - heavy banding in dark areas and bigger gradients

close up of reduced color palette and banding:

**System Information** Operating system: win11 Graphics card: rtx3060 **Blender Version** any newer version 4.0 /4.1 Worked: 3.6 **Short description of error** When rendering with viewport rendering, the output has heavy banding. Must be some conversion error, as you can see the screenshot of the viewport looks just fine, as do the textures in every other programs. this problem persists , no matter if viewport compositing is enabled or not. the whole image looks like a bad gif with reduced colors. **Step to Reproduce** - Open attached file - Switch to viewport render - `View -> Viewport Render Image` [banding_demo.blend](https://projects.blender.org/attachments/674542f2-1741-45e8-9be9-cd06db858b25) | viewport - looks fine | viewport render - banding | | -- | -- | | ![grafik](/attachments/885a022f-9f1b-402c-be64-c5a3c92ad91c) | ![grafik](/attachments/919c97cf-76b5-43b0-ad16-26f4e1510e3b) | <details> <summary> Original report </summary> Viewport screenshot - looks absolutely fine ![grafik](/attachments/ee9c7ae8-d7cd-4977-a36e-1b06d1daf730) normal render - looks absolutely fine ![grafik](/attachments/2b29dfc4-bdee-4a93-a37e-31ae2c637f5c) viewport render - heavy banding in dark areas and bigger gradients ![grafik](/attachments/1e160cc6-e345-4bd5-a60b-e584b5acec2a) close up of reduced color palette and banding: ![grafik](/attachments/05a2c786-9594-4d03-8d50-15e5de02433a) </details>

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Alex Mehler added the

labels 2023-10-05 00:33:31 +02:00

Pratik Borhade commented

2023-10-05 05:37:46 +02:00

Hi, thanks for the report. Any improvement in result after changing sampling count, color depth, file output format, etc.?
Color banding in dark areas might be expected in some cases when displaying images on digital display.

Hi, thanks for the report. Any improvement in result after changing sampling count, color depth, file output format, etc.? Color banding in dark areas might be expected in some cases when displaying images on digital display.

Pratik Borhade added

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labels 2023-10-05 05:37:56 +02:00

Pratik Borhade commented

2023-10-05 05:38:22 +02:00

Maybe related #104298?

Alex Mehler commented

2023-10-06 12:12:25 +02:00

Hi, thanks for the report. Any improvement in result after changing sampling count, color depth, file output format, etc.?
Color banding in dark areas might be expected in some cases when displaying images on digital display.

no , doesnt change anything .. the problem seems to be in the calculation , a value must be too high or too low. as you can see just screenshotting the viewport has perfectly nice colors and good looking gradients .. its just when blender grabs the viewport that this happens in the conversion.

here i blew out the gamma and made a close up so that its easier to see, its not just in the dark areas but everywhere there are color bandings

viewport screenshot - looks fine

viewport render - looks wrong

edit: same thing happens with normal geometry without any textures:

viewport screenshot -looks fine

viewport render - banding

> Hi, thanks for the report. Any improvement in result after changing sampling count, color depth, file output format, etc.? > Color banding in dark areas might be expected in some cases when displaying images on digital display. no , doesnt change anything .. the problem seems to be in the calculation , a value must be too high or too low. as you can see just screenshotting the viewport has perfectly nice colors and good looking gradients .. its just when blender grabs the viewport that this happens in the conversion. here i blew out the gamma and made a close up so that its easier to see, its not just in the dark areas but everywhere there are color bandings viewport screenshot - looks fine ![grafik](/attachments/91bdd5c6-2ae8-47dc-af33-41f44e31b450) viewport render - looks wrong ![grafik](/attachments/9bd0b7a2-2199-445f-80e5-e78c13ef9bb1) edit: same thing happens with normal geometry without any textures: viewport screenshot -looks fine ![grafik](/attachments/9e9de944-b94b-4c3f-84cd-7cd73c30c19f) viewport render - banding ![grafik](/attachments/f2a17a84-1e9d-46c2-9508-5d2e859ff653)

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Alex Mehler commented

2023-10-07 11:51:47 +02:00

if you point me to the related code in blender repository , would e nice

Pratik Borhade commented

2023-10-09 11:32:05 +02:00

Unable to redo in simple file. Could you share example file with us?

if you point me to the related code in blender repository , would e nice

Cycles code is located in intern\cycles\blender. I'm not sure which factors are affecting this, so can not really tell exact file/code-block to look at.
Cycles devs know better about it.

Unable to redo in simple file. Could you share example file with us? > if you point me to the related code in blender repository , would e nice Cycles code is located in `intern\cycles\blender`. I'm not sure which factors are affecting this, so can not really tell exact file/code-block to look at. Cycles devs know better about it.

Alex Mehler changed title from ~~Viewport rendering, heavy banding problems.~~ to Viewport rendering in EEVEE -> heavy banding problems.

2023-10-10 09:00:05 +02:00

Alex Mehler commented

2023-10-10 12:46:44 +02:00

Unable to redo in simple file. Could you share example file with us?

if you point me to the related code in blender repository , would e nice

Cycles code is located in intern\cycles\blender. I'm not sure which factors are affecting this, so can not really tell exact file/code-block to look at.
Cycles devs know better about it.

These are eevee renderings and viewport, i changed the title accordingly. sorry
here i made a testfile:

a gp object and textured plane and a sphere .. all have banding and/or color grizz
like i said it happens with or without viewport compositor , and encompasses all objects , so it should happen somewhere in the capture module or following conversion , not before in object/shaders/whatever

viewport - looks fine

viewport render - banding

> Unable to redo in simple file. Could you share example file with us? > > if you point me to the related code in blender repository , would e nice > > Cycles code is located in `intern\cycles\blender`. I'm not sure which factors are affecting this, so can not really tell exact file/code-block to look at. > Cycles devs know better about it. These are eevee renderings and viewport, i changed the title accordingly. sorry here i made a testfile: a gp object and textured plane and a sphere .. all have banding and/or color grizz like i said it happens with or without viewport compositor , and encompasses all objects , so it should happen somewhere in the capture module or following conversion , not before in object/shaders/whatever viewport - looks fine ![grafik](/attachments/885a022f-9f1b-402c-be64-c5a3c92ad91c) viewport render - banding ![grafik](/attachments/919c97cf-76b5-43b0-ad16-26f4e1510e3b)

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banding_demo.blend

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Alex Mehler commented

2023-10-11 17:51:49 +02:00

OK , i got it .. the bug was introduced in blender build August 09, 18:54:32 15124fe490

https://projects.blender.org/blender/blender/commit/15124fe49090

i dont see what in that commit would change the behaviour though .. but the version prior to this renders fine.

@fclem

OK , i got it .. the bug was introduced in blender build August 09, 18:54:32 15124fe49090 https://projects.blender.org/blender/blender/commit/15124fe49090 i dont see what in that commit would change the behaviour though .. but the version prior to this renders fine. @fclem

Pratik Borhade added

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labels 2023-10-12 13:22:36 +02:00

Pratik Borhade commented

2023-10-17 07:52:37 +02:00

Thanks for the file. Unable to confirm though: image
Does this happen with factory settings (to eliminate interference of additional scripts, add-ons, etc.)?: File > Defaults > Load Factory Settings

Thanks for the file. Unable to confirm though: [image](/attachments/29565a26-510e-44cd-b731-e626e425c7ae) Does this happen with factory settings (to eliminate interference of additional scripts, add-ons, etc.)?: `File > Defaults > Load Factory Settings`

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Pratik Borhade added

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labels 2023-10-17 07:52:46 +02:00

Alex Mehler commented

2023-10-17 23:33:09 +02:00

Thanks for the file. Unable to confirm though: image
Does this happen with factory settings (to eliminate interference of additional scripts, add-ons, etc.)?: File > Defaults > Load Factory Settings

Yes its happening on default settings too.

Did you use viewport rendering though ? , View -> Viewport Render Image . Normally viewport render doesnt show render statistics.

> Thanks for the file. Unable to confirm though: [image](/attachments/29565a26-510e-44cd-b731-e626e425c7ae) > Does this happen with factory settings (to eliminate interference of additional scripts, add-ons, etc.)?: `File > Defaults > Load Factory Settings` Yes its happening on default settings too. Did you use viewport rendering though ? , View -> Viewport Render Image . Normally viewport render doesnt show render statistics.

Alex Mehler commented

2023-10-18 00:03:44 +02:00

This may also be related:

The old behaviour for viewport rendering , has exact color reproduction in the render.
The image shows the eevee viewport and a viewport render in a very small window. As you can see the colors are matching.

The new behaviour (since build August 09, 18:54:32). Here you can see that the colors are slightly shifted in the render. Its probably easier to see in the yellow than the orange even , turned from orangy glowy yellow to dirty greenish yellow , darker parts in the orange are cutoff and replaced with saturation instead .. there must be some undetected color conversion issue in the code now.

This may also be related: The old behaviour for viewport rendering , has exact color reproduction in the render. The image shows the eevee viewport and a viewport render in a very small window. As you can see the colors are matching. ![grafik](/attachments/6bf224e5-b0ec-4f5c-a7ab-faa5fc4304fb) The new behaviour (since build August 09, 18:54:32). Here you can see that the colors are slightly shifted in the render. Its probably easier to see in the yellow than the orange even , turned from orangy glowy yellow to dirty greenish yellow , darker parts in the orange are cutoff and replaced with saturation instead .. there must be some undetected color conversion issue in the code now. ![grafik](/attachments/c92ad11e-0b16-4265-8bdd-354477d7ca97)

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Pratik Borhade commented

2023-10-18 12:11:33 +02:00

View -> Viewport Render Image . Normally viewport render doesnt show render statistics.

Nice catch, thanks 🙂

I assume problem is with final render image

> View -> Viewport Render Image . Normally viewport render doesnt show render statistics. Nice catch, thanks 🙂 I assume problem is with final render image

Pratik Borhade added

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labels 2023-10-18 12:12:01 +02:00

Pratik Borhade changed title from ~~Viewport rendering in EEVEE -> heavy banding problems.~~ to Regression: EEVEE Color banding in viewport image render

2023-10-18 12:13:08 +02:00

Pratik Borhade added this to the 4.0 milestone 2023-10-18 12:17:24 +02:00

Miguel Pozo commented

2023-10-18 20:29:32 +02:00

Caused by 2367ed2ef2.
@Michael-Parkin-White-Apple, any pointer?

Caused by 2367ed2ef241846d99fc8bab73abad4d48b9e67b. @Michael-Parkin-White-Apple, any pointer?

Clément Foucault commented

2023-10-20 17:12:04 +02:00

@pragma37 Looks like the changes in view3d_draw.cc are what caused it. Can you confirm?

@pragma37 Looks like the changes in `view3d_draw.cc` are what caused it. Can you confirm?

Alex Mehler commented

2023-10-21 02:56:38 +02:00

@pragma37 Looks like the changes in view3d_draw.cc are what caused it. Can you confirm?

please note that this solely affects the viewport render , not the normal render(F12). The normal render looks fine.
So maybe the changes implemented there can be ported to viewport render . Someone probably just overlooked/forgot it. ??

> @pragma37 Looks like the changes in `view3d_draw.cc` are what caused it. Can you confirm? please note that this solely affects the viewport render , not the normal render(F12). The normal render looks fine. So maybe the changes implemented there can be ported to viewport render . Someone probably just overlooked/forgot it. ??

Clément Foucault commented

2023-10-23 12:32:13 +02:00

I have the fix. Will commit.

❤️ 1

Clément Foucault referenced a pull request that will close this issue

2023-10-23 12:53:11 +02:00

Fix #113266: Viewport: Color banding in viewport image render #114061

Clément Foucault referenced this issue from a commit

2023-10-23 13:10:06 +02:00

Fix #113266: Viewport: Color banding in viewport image render

Clément Foucault closed this issue

2023-10-23 13:10:10 +02:00