Texture Painting not updating cycles shader in viewport #86787

New Issue

Willem Odendaal · 2021-03-21T14:07:11+01:00

Willem Odendaal commented

2021-03-21 14:07:11 +01:00

System Information
Operating system: Linux-5.8.0-44-generic-x86_64-with-debian-bullseye-sid 64 Bits
Graphics card: Mesa Intel(R) Xe Graphics (TGL GT2) Intel 4.6 (Core Profile) Mesa 20.2.6

Blender Version
Broken: version: 2.92.0, branch: master, commit date: 2021-02-24 16:25, hash: 02948a2cab
Worked: (newest version of Blender that worked as expected)

Short description of error
[Please fill out a short description of the error here]

Level 1. When texture painting in the 3D viewport, the image is updated, but the visible shader on the object doesn't update in cycles until switching to viewport shading and back to cycles.
It still works when switching to Eevee shading. When reloading the image in the shader image texture node, it updates in cycles, but the problem persists when the image is updated (painted on) again.

Level 2. The above bug becomes worse as follows:

In cycles the image stops updating even when switching to viewport shading and back to cycles.
(A)-When reloading the image in the shader image texture node, it updates in cycles, but any new paint on the texture in the viewport or image editor -> paint mode won't update until step A is repeated.

I do not know exactly what triggers this 2nd level bug, but it doesn't take long to show up.
I was able to repeat it just by painting and switching between Eevee and cycles using my test .blend file (attached)

Exact steps for others to reproduce the error
[Please describe the exact steps needed to reproduce the issue]
[Based on the default startup or an attached .blend file (as simple as possible)]

Assign a material with an image node to an unwrapped object
Switch to viewport texture painting and start painting on the image in cycles shading.
The image updates in viewport shading, but not the visible shader on the object in cycles.
Switch to Eevee shading - now eveything works as expected.
I do not know what triggers the level 2 bug.

Cycles not painting on Cube.blend

**System Information** Operating system: Linux-5.8.0-44-generic-x86_64-with-debian-bullseye-sid 64 Bits Graphics card: Mesa Intel(R) Xe Graphics (TGL GT2) Intel 4.6 (Core Profile) Mesa 20.2.6 **Blender Version** Broken: version: 2.92.0, branch: master, commit date: 2021-02-24 16:25, hash: `02948a2cab` Worked: (newest version of Blender that worked as expected) **Short description of error** [Please fill out a short description of the error here] Level 1. When texture painting in the 3D viewport, the image is updated, but the visible shader on the object doesn't update in cycles until switching to viewport shading and back to cycles. It still works when switching to Eevee shading. When reloading the image in the shader image texture node, it updates in cycles, but the problem persists when the image is updated (painted on) again. Level 2. The above bug becomes worse as follows: In cycles the image stops updating even when switching to viewport shading and back to cycles. (A)-When reloading the image in the shader image texture node, it updates in cycles, but any new paint on the texture in the viewport or image editor -> paint mode won't update until step A is repeated. I do not know exactly what triggers this 2nd level bug, but it doesn't take long to show up. I was able to repeat it just by painting and switching between Eevee and cycles using my test .blend file (attached) **Exact steps for others to reproduce the error** [Please describe the exact steps needed to reproduce the issue] [Based on the default startup or an attached .blend file (as simple as possible)] 1. Assign a material with an image node to an unwrapped object 2. Switch to viewport texture painting and start painting on the image in cycles shading. 3. The image updates in viewport shading, but not the visible shader on the object in cycles. 4. Switch to Eevee shading - now eveything works as expected. 5. I do not know what triggers the level 2 bug. [Cycles not painting on Cube.blend](https://archive.blender.org/developer/F9902448/Cycles_not_painting_on_Cube.blend)

Willem Odendaal commented

2021-03-21 14:07:11 +01:00

Added subscriber: @DeXoN

blender-admin commented

2021-03-21 14:07:11 +01:00

#103655 was marked as duplicate of this issue

blender-admin commented

2021-03-21 14:07:11 +01:00

#101032 was marked as duplicate of this issue

Philipp Oeser commented

2021-03-22 10:03:46 +01:00

Added subscriber: @lichtwerk

Philipp Oeser commented

2021-03-22 10:03:46 +01:00

Changed status from 'Needs Triage' to: 'Confirmed'

Philipp Oeser commented

2021-03-22 10:03:46 +01:00

This is a known limitation.

Cycles works best with files saved to disk.
There were reports about this before, these were normally closed, but I think it does not do harm to have one report for this open as reference.
Note this will probably be tackled with #54656 (Cycles/Eevee texture nodes for modifiers, painting and more)

This is a known limitation. Cycles works best with files saved to disk. There were reports about this before, these were normally closed, but I think it does not do harm to have one report for this open as reference. Note this will probably be tackled with #54656 (Cycles/Eevee texture nodes for modifiers, painting and more)

Jason Lai commented

2021-10-07 08:48:13 +02:00

Added subscriber: @Jason-Lai

Doug Cox commented

2022-02-21 23:28:59 +01:00

Added subscriber: @ziflin

Doug Cox commented

2022-02-21 23:34:45 +01:00

I can confirm this still occurs in v3.0. Cycles stops rendering changes made to textures (Texture Paint in 2d or 3d) for externally saved textures. This happens fairly often when painting in Material Preview mode using Evee and switching to Rendered mode using Cycles. I'm unable to get Cycles viewport renderers to update/refresh the texture by any means that I can think of other than restarting Blender.

It clearly seems like a bug as it works fine until it stops. It seriously needs to be fixed as it makes trying to preview texturing painting in Cycles useless when it occurs.

I can confirm this still occurs in v3.0. Cycles stops rendering changes made to textures (Texture Paint in 2d or 3d) for externally saved textures. This happens fairly often when painting in Material Preview mode using Evee and switching to Rendered mode using Cycles. I'm unable to get Cycles viewport renderers to update/refresh the texture by any means that I can think of other than restarting Blender. It clearly seems like a bug as it works fine until it stops. It seriously needs to be fixed as it makes trying to preview texturing painting in Cycles useless when it occurs.

Omar Emara commented

2022-09-13 15:33:39 +02:00

Added subscribers: @Piergiorgio_PG, @OmarEmaraDev