File explorer thumbnail renders as a black image when using cycles rendered preview 3.0 #92628

New Issue

Kenneth Yuen · 2021-10-29T23:15:27+02:00

Kenneth Yuen commented

2021-10-29 23:15:27 +02:00

System Information
Operating system: Windows-10-10.0.19042-SP0 64 Bits
Graphics card: NVIDIA GeForce GTX 1060/PCIe/SSE2 NVIDIA Corporation 4.5.0 NVIDIA 471.41

Blender Version
Broken: version: 3.0.0 Beta, branch: master, commit date: 2021-10-28 23:23, hash: b43077ba3a
Worked: version: New feature in 3.0

Short description of error
File explorer thumbnail renders as black image using cycles, when Camera View is selected in user preferences' preview type drop-down.
It works when rendered as wireframe, solid, and material preview, and render preview when using eevee.

Exact steps for others to reproduce the error

Open default scene
Ensure your user preferences' preview type is set to Camera View.
Switch to cycles render engine
Enter Render Preview mode in the viewport
Save file
Observe that the .blend file thumbnail is empty

This doesn't occur if there's no Camera or if Eevee is used as the render engine for example.

[Original repro steps below here]
Open blender, add a cube, add a material with voroni texture as base color, switch to rendered preview, add camera, add sun, save file, shows black thumbnail in file explorer.

Test.
I turned off all add-ons beside cycles and saved, and it rendered the rendered preview(can't replicate this so I might have disabled the cycles addon and turned it back on, which automatically switched it to eevee and that's what I saw).
I closed the blend file, opened a new blend, repeat setup, saved, thumbnail is black.

Tried turning on all addons on, save, black thumbnail.
Turned off all but cycles, save, black thumbnail

Cycles.blend
system-info.txt

**System Information** Operating system: Windows-10-10.0.19042-SP0 64 Bits Graphics card: NVIDIA GeForce GTX 1060/PCIe/SSE2 NVIDIA Corporation 4.5.0 NVIDIA 471.41 **Blender Version** Broken: version: 3.0.0 Beta, branch: master, commit date: 2021-10-28 23:23, hash: `b43077ba3a` Worked: version: New feature in 3.0 **Short description of error** File explorer thumbnail renders as black image using cycles, when `Camera View` is selected in user preferences' preview type drop-down. It works when rendered as wireframe, solid, and material preview, and render preview when using eevee. ![preview thumbnails.png](https://archive.blender.org/developer/F11604993/preview_thumbnails.png) **Exact steps for others to reproduce the error** - Open default scene - Ensure your user preferences' preview type is set to `Camera View`. - Switch to cycles render engine - Enter Render Preview mode in the viewport - Save file - Observe that the .blend file thumbnail is empty This doesn't occur if there's no Camera or if Eevee is used as the render engine for example. [Original repro steps below here] Open blender, add a cube, add a material with voroni texture as base color, switch to rendered preview, add camera, add sun, save file, shows black thumbnail in file explorer. Test. I turned off all add-ons beside cycles and saved, and it rendered the rendered preview(can't replicate this so I might have disabled the cycles addon and turned it back on, which automatically switched it to eevee and that's what I saw). I closed the blend file, opened a new blend, repeat setup, saved, thumbnail is black. Tried turning on all addons on, save, black thumbnail. Turned off all but cycles, save, black thumbnail [Cycles.blend](https://archive.blender.org/developer/F11604984/Cycles.blend) [system-info.txt](https://archive.blender.org/developer/F11605038/system-info.txt)

Kenneth Yuen commented

2021-10-29 23:15:27 +02:00

Added subscriber: @Kenneth-Yuen

Jesse Yurkovich commented

2021-11-27 22:40:01 +01:00

Added subscriber: @deadpin

Jesse Yurkovich commented

2021-11-27 22:40:01 +01:00

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

Jesse Yurkovich commented

2021-11-27 22:40:01 +01:00

Can confirm here that a Camera + being in Cycles render preview mode causes a blank thumbnail. Will simplify repro steps as next change.

Bastien Montagne commented

2021-11-29 11:23:15 +01:00

Added subscribers: @Sergey, @Jeroen-Bakker, @brecht, @mont29

Bastien Montagne commented

2021-11-29 11:23:15 +01:00

I think the offscreen GPU rendering code (ED_view3d_draw_offscreen_imbuf etc.) is simply not designed to work with deferred renderings like Cycles ones?

@Jeroen-Bakker or @Sergey/@brecht should know more, but I have the feeling this should be forcefully down-graded to an actual GPU rendering... Not a #core issue anyway, more for the #eevee_viewport and/or #render_cycles modules.

I think the offscreen GPU rendering code (`ED_view3d_draw_offscreen_imbuf` etc.) is simply not designed to work with deferred renderings like Cycles ones? @Jeroen-Bakker or @Sergey/@brecht should know more, but I have the feeling this should be forcefully down-graded to an actual GPU rendering... Not a #core issue anyway, more for the #eevee_viewport and/or #render_cycles modules.

Brecht Van Lommel commented

2021-11-29 14:43:53 +01:00

Added subscriber: @Harley

Brecht Van Lommel commented

2021-11-29 14:43:53 +01:00

This feature was added by @harley.

Indeed Cycles should not be used here. Also with Eevee this can behave poorly. The save operation is blocked until all shaders are compiled and images textures are loaded, which can take a long time in real world .blend files.

This feature was added by @harley. Indeed Cycles should not be used here. Also with Eevee this can behave poorly. The save operation is blocked until all shaders are compiled and images textures are loaded, which can take a long time in real world .blend files.

Brecht Van Lommel commented

2021-11-29 14:59:31 +01:00

Added subscriber: @ideasman42

Brecht Van Lommel commented

2021-11-29 14:59:31 +01:00

I suggest to remove the usage of the 3D viewport shading type and settings for preview generation, and change it back to solid.

This is nice in theory but for real production files, we just can't be generating GI probes, rendering shadow maps, compiling shaders, ... on .blend file save. Especially not as the default setting in the user preferences.

I suggest to remove the usage of the 3D viewport shading type and settings for preview generation, and change it back to solid. This is nice in theory but for real production files, we just can't be generating GI probes, rendering shadow maps, compiling shaders, ... on .blend file save. Especially not as the default setting in the user preferences.

blender-admin commented

2021-11-29 15:25:39 +01:00

This issue was referenced by 2206b6b9a0

This issue was referenced by 2206b6b9a04777b7325c8f30a49db23bc9a61317

Brecht Van Lommel commented

2021-11-29 16:29:31 +01:00

Changed status from 'Confirmed' to: 'Resolved'

Brecht Van Lommel closed this issue

2021-11-29 16:29:31 +01:00

Brecht Van Lommel self-assigned this 2021-11-29 16:29:31 +01:00

Thomas Dinges added this to the 3.0 milestone 2023-02-08 15:58:48 +01:00

Sign in to join this conversation.

No Label

Download

What's New

Blender Studio

Manual

Developers Blog

Documentation

Benchmark

Blender Conference

Development Fund

One-time Donations

File explorer thumbnail renders as a black image when using cycles rendered preview 3.0 #92628