Alembic with hair and motion blur flickers on render #92888

New Issue

Yegor · 2021-11-06T22:54:02+01:00

Yegor commented

2021-11-06 22:54:02 +01:00

System Information
Operating system: Linux-5.4.0-88-generic-x86_64-with-glibc2.31 64 Bits
Graphics card: GeForce GTX 1080 Ti/PCIe/SSE2 NVIDIA Corporation 4.5.0 NVIDIA 460.91.03

Blender Version
Broken: version: 3.0.0 Beta, branch: master, commit date: 2021-10-27 22:07, hash: b838eaf2b9, 2.93.6
Worked: 2.83.19

Short description of error
Alembic with a hair system on it with motion blur enabled flickers on render. No options, reexporting, triangulation (it's already triangulated), pc2 or mdd can help. I tried every possible solution. Please notice that it happens even without children hair. It works correctly in 2.83.19 though, so it's a huge regression.
Growing hair on alembic is a common practice in heterogeneous software environment and I have to fall back to 2.83.19 for our project because of this issue.
0001-0100.mp4

Exact steps for others to reproduce the error
Open the file. Render out the sequence.
abc_hair_mblur_bug.blend

abc_hair_mblur_bug.abc

**System Information** Operating system: Linux-5.4.0-88-generic-x86_64-with-glibc2.31 64 Bits Graphics card: GeForce GTX 1080 Ti/PCIe/SSE2 NVIDIA Corporation 4.5.0 NVIDIA 460.91.03 **Blender Version** Broken: version: 3.0.0 Beta, branch: master, commit date: 2021-10-27 22:07, hash: `b838eaf2b9`, 2.93.6 Worked: 2.83.19 **Short description of error** Alembic with a hair system on it with motion blur enabled flickers on render. No options, reexporting, triangulation (it's already triangulated), pc2 or mdd can help. I tried every possible solution. Please notice that it happens even without children hair. It works correctly in 2.83.19 though, so it's a huge regression. Growing hair on alembic is a common practice in heterogeneous software environment and I have to fall back to 2.83.19 for our project because of this issue. [0001-0100.mp4](https://archive.blender.org/developer/F11753394/0001-0100.mp4) **Exact steps for others to reproduce the error** Open the file. Render out the sequence. [abc_hair_mblur_bug.blend](https://archive.blender.org/developer/F11753399/abc_hair_mblur_bug.blend) [abc_hair_mblur_bug.abc](https://archive.blender.org/developer/F11753400/abc_hair_mblur_bug.abc)

Yegor commented

2021-11-06 22:54:02 +01:00

Added subscriber: @YegorSmirnov

Omar Emara commented

2022-02-08 14:49:19 +01:00

Added subscriber: @OmarEmaraDev

Omar Emara commented

2022-02-08 14:49:19 +01:00

Changed status from 'Needs Triage' to: 'Needs User Info'

Omar Emara commented

2022-02-08 14:49:19 +01:00

I can't reproduce this using latest master. Can you try with the latest daily build? https://builder.blender.org/download/
It should be noted that I rendered the animation on the CPU and this might be an Nvidea GPU only thing. Can you try different compute backends? Does CPU suffer from the same issue? What about CUDA and OPTIX?

I can't reproduce this using latest master. Can you try with the latest daily build? https://builder.blender.org/download/ It should be noted that I rendered the animation on the CPU and this might be an Nvidea GPU only thing. Can you try different compute backends? Does CPU suffer from the same issue? What about CUDA and OPTIX?

Yegor commented

2022-02-08 15:51:11 +01:00

You are correct only GPU (Cuda) affected. Cpu runs smoothly. By the way, looks like it's the same issue as #95305 and it's not related to alembic.

Omar Emara commented

2022-02-08 15:54:47 +01:00

@YegorSmirnov If it is the case, then we can merge those two reports.

Omar Emara commented

2022-02-08 16:02:58 +01:00

Closed as duplicate of #95305

Omar Emara closed this issue

2022-02-08 16:02:58 +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

Alembic with hair and motion blur flickers on render #92888