# Possible 9.6.0 regression with environment texture rendering
**URL:** https://discourse.vtk.org/t/possible-9-6-0-regression-with-environment-texture-rendering/16247
**Category:** Development
**Created:** [January 20, 2026, 6:09am UTC](https://discourse.vtk.org/t/possible-9-6-0-regression-with-environment-texture-rendering/16247 "2026-01-20T06:09:56Z")
**Posts on this page:** 9
**Page:** 1
### Author:  [@user27182](https://discourse.vtk.org/u/user27182)
#### Post date: [January 20, 2026, 6:09am UTC](https://discourse.vtk.org/t/possible-9-6-0-regression-with-environment-texture-rendering/16247/1 "2026-01-20T06:09:56Z")
The following script loads a cube map as a skybox environment texture and plots a metallic sphere with PBR.
[env\_texture.py](https://discourse.vtk.org/uploads/short-url/pTA1jM8QojTBvfl4wdaIKRpeXZJ.py) (2.8 KB)
[cubemap\_park.zip](https://discourse.vtk.org/uploads/short-url/oQWcm6FYNU8MDPWxw2gIV0xlpcN.zip) (592.7 KB)
Usage: download script and unzip cubemap files. Then run
```auto
python env_texture.py cubemap_park
```
With `vtk==9.5.2`, we get this image, where the reflection is showing what’s _behind_ the camera. This appears correct to me.
But with `vtk==9.6.0rc2`, we get this instead, where the reflection is showing the same contents as the foreground image.
This seems like a regression, but I am not sure… maybe someone can comment on whether this is a bug or is intentional?
By installing the dev wheels, I was able to confirm that we get the first image with `vtk==9.5.20250830.dev0`, and we get the second with `vtk-9.5.20250913.dev0`, so the change occurred between Aug 30 and Sept 13.
I think perhaps this commit may be the cause of the change?
[https://gitlab.kitware.com/vtk/vtk/-/commit/2ec9432207980adf303e2266d4c5485f638a4269](https://gitlab.kitware.com/vtk/vtk/-/commit/2ec9432207980adf303e2266d4c5485f638a4269)
I believe it was committed to master Sep 8.
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### Author:  [@mwestphal](https://discourse.vtk.org/u/mwestphal)
#### Post date: [January 20, 2026, 7:45am UTC](https://discourse.vtk.org/t/possible-9-6-0-regression-with-environment-texture-rendering/16247/2 "2026-01-20T07:45:46Z")
@LucasGandel @lgivord
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### Author:  [@lgivord](https://discourse.vtk.org/u/lgivord)
#### Post date: [January 20, 2026, 9:56am UTC](https://discourse.vtk.org/t/possible-9-6-0-regression-with-environment-texture-rendering/16247/3 "2026-01-20T09:56:52Z")
I reproduce the issue on Linux too, I’ll take a look.
Thanks also for the bisect, it’s very useful 🙂
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### Author:  [@lgivord](https://discourse.vtk.org/u/lgivord)
#### Post date: [January 20, 2026, 10:16am UTC](https://discourse.vtk.org/t/possible-9-6-0-regression-with-environment-texture-rendering/16247/4 "2026-01-20T10:16:37Z")
here is the issue : [https://gitlab.kitware.com/vtk/vtk/-/issues/19910](https://gitlab.kitware.com/vtk/vtk/-/issues/19910)
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### Author:  [@lgivord](https://discourse.vtk.org/u/lgivord)
#### Post date: [January 23, 2026, 7:19am UTC](https://discourse.vtk.org/t/possible-9-6-0-regression-with-environment-texture-rendering/16247/5 "2026-01-23T07:19:42Z")
@user27182 FYI the issue is resolved, it should be testable in the wheel generated tomorrow.
Thanks for your bug report and for testing the RC2 🙂
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### Author:  [@mwestphal](https://discourse.vtk.org/u/mwestphal)
#### Post date: [January 23, 2026, 8:01am UTC](https://discourse.vtk.org/t/possible-9-6-0-regression-with-environment-texture-rendering/16247/6 "2026-01-23T08:01:48Z")
It will even be present in the 9.6.0-RC3.
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### Author:  [@user27182](https://discourse.vtk.org/u/user27182)
#### Post date: [January 26, 2026, 7:51am UTC](https://discourse.vtk.org/t/possible-9-6-0-regression-with-environment-texture-rendering/16247/7 "2026-01-26T07:51:56Z")
Thanks for the fix! Looks like the dev wheels upload didn’t succeed:
I’ll try again later with either the next dev wheel or with RC3, probably will try both whenever they’re uploaded.
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### Author:  [@mwestphal](https://discourse.vtk.org/u/mwestphal)
#### Post date: [January 26, 2026, 8:27am UTC](https://discourse.vtk.org/t/possible-9-6-0-regression-with-environment-texture-rendering/16247/8 "2026-01-26T08:27:01Z")
Ill let you know when they are
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### Author:  [@user27182](https://discourse.vtk.org/u/user27182)
#### Post date: [February 1, 2026, 3:47pm UTC](https://discourse.vtk.org/t/possible-9-6-0-regression-with-environment-texture-rendering/16247/9 "2026-02-01T15:47:54Z")
rc3 wheels were published yesterday, can confirm this is fixed 👍