Adaptive Subdivision - Stray vertex / Spikes #72193

New Issue

getshi · 2019-12-05T10:50:35+01:00

getshi commented

2019-12-05 10:50:35 +01:00

System Information
Operating system: Ubuntu 18.04
Graphics card: GTX 1080 Ti

Blender Version
Broken: 2.81 2019-12-05

Short description of error
I'm using adaptive subdivision for micro-displacements to turn a surface mesh into a thick scarf with yarn geometry. In some of my animation's frames I have found spikes in the rendering such as here:

It seems to be deterministic in that I can reproduce it for a single frame of the animation; I attached the blend file for a minimal example of a single frame with the issue.
This issue does not happen in the progressive viewport render. Also, since the ao-map that I'm using to drive the displacement does not change over time but this happens only in some frames, it is likely not related to the displacement map but more to the mesh and the adaptive subdivisions.

Exact steps for others to reproduce the error
Open the blend file and press F12 to render
adaptivesubdiv_issue_updated.blend

**System Information** Operating system: Ubuntu 18.04 Graphics card: GTX 1080 Ti **Blender Version** Broken: 2.81 2019-12-05 **Short description of error** I'm using adaptive subdivision for micro-displacements to turn a surface mesh into a thick scarf with yarn geometry. In some of my animation's frames I have found spikes in the rendering such as here: ![Issue.png](https://archive.blender.org/developer/F8191191/Issue.png) It seems to be deterministic in that I can reproduce it for a single frame of the animation; I attached the blend file for a minimal example of a single frame with the issue. This issue does not happen in the progressive viewport render. Also, since the ao-map that I'm using to drive the displacement does not change over time but this happens only in some frames, it is likely not related to the displacement map but more to the *mesh and the adaptive subdivisions*. **Exact steps for others to reproduce the error** Open the blend file and press F12 to render [adaptivesubdiv_issue_updated.blend](https://archive.blender.org/developer/F8322948/adaptivesubdiv_issue_updated.blend)

getshi commented

2019-12-05 10:50:35 +01:00

Added subscriber: @getshi

blender-admin commented

2019-12-05 10:50:35 +01:00

#75068 was marked as duplicate of this issue

Germano Cavalcante commented

2019-12-06 15:22:31 +01:00

Added subscribers: @MaiLavelle, @mano-wii

Germano Cavalcante commented

2019-12-06 15:22:31 +01:00

I can confirm the spike.

Operating system: Windows-10-10.0.18941 64 Bits
Graphics card: Radeon (TM) RX 480 Graphics

@MaiLavelle, is this something you've worked on?

I can confirm the spike. **Operating system:** Windows-10-10.0.18941 64 Bits **Graphics card:** Radeon (TM) RX 480 Graphics @MaiLavelle, is this something you've worked on?

Germano Cavalcante commented

2020-01-25 00:15:56 +01:00

Changed status from 'Confirmed' to: 'Resolved'

Germano Cavalcante closed this issue

2020-01-25 00:15:56 +01:00

Germano Cavalcante self-assigned this 2020-01-25 00:15:56 +01:00

Germano Cavalcante commented

2020-01-25 00:15:56 +01:00

This has already been fixed in blender 2.83. Probably by blender/cycles@fb54d4f307

getshi commented

2020-02-05 09:45:33 +01:00

Sadly this only fixed the one frame, or rather it shifts the issue to other frames.
A fully rendered animation shows more stray vertices:
hylc_scarf_cam_anim.mp4

I'm including another problematic frame as of Blender v2.83.2 (Date 2020-02-04 10:08)
adaptivesubdiv_issue_updated.blend

I'm only including one frame because all frames would get large in terms of file size (and I render by loading only individual frames).

Sadly this only fixed the one frame, or rather it shifts the issue to other frames. A fully rendered animation shows more stray vertices: [hylc_scarf_cam_anim.mp4](https://archive.blender.org/developer/F8322952/hylc_scarf_cam_anim.mp4) I'm including another problematic frame as of Blender v2.83.2 (Date 2020-02-04 10:08) [adaptivesubdiv_issue_updated.blend](https://archive.blender.org/developer/F8322948/adaptivesubdiv_issue_updated.blend) I'm only including one frame because all frames would get large in terms of file size (and I render by loading only individual frames).

Germano Cavalcante commented

2020-02-05 12:47:29 +01:00

Changed status from 'Resolved' to: 'Needs Developer To Reproduce'

Germano Cavalcante reopened this issue

2020-02-05 12:47:29 +01:00

Germano Cavalcante commented

2020-02-05 12:47:29 +01:00

I couldn't reproduce the problem here.
Are you sure you chose the right frame?

I couldn't reproduce the problem here. Are you sure you chose the right frame?

getshi commented

2020-02-05 13:35:15 +01:00

I've redownloaded the blend file and pressed F12 giving me the following rendering in progress:

I get the stray vertex consistently. I also quickly retried with the newest 2.83 (February 05, 00:07:55 - 79003fa0c4) and the issue remains.

I've redownloaded the blend file and pressed F12 giving me the following rendering in progress: ![screenshot.png](https://archive.blender.org/developer/F8323364/screenshot.png) I get the stray vertex consistently. I also quickly retried with the newest 2.83 (February 05, 00:07:55 - 79003fa0c415) and the issue remains.

Germano Cavalcante commented

2020-02-05 14:22:03 +01:00

Changed status from 'Needs Developer To Reproduce' to: 'Confirmed'