Vertex Slide and Loop Cut and Slide tools breaks the UVs and Vertex Colors after topology changes [new or deleted] (if CustomSplitNormals are present) #81060

New Issue

Yan Kansky · 2020-09-22T17:01:33+02:00

Yan Kansky commented

2020-09-22 17:01:33 +02:00

System Information
Operating system: Windows-10-10.0.18362-SP0 64 Bits
Graphics card: GeForce GTX 980/PCIe/SSE2 NVIDIA Corporation 4.5.0 NVIDIA 441.87

Blender Version
Broken: version: 2.91.0 Alpha, branch: master, commit date: 2020-09-22 12:02, hash: 8d1123ba22
Worked: Blender 2.83 LTS
Caused by 93c8955a7

Short description of error
Vertex Slide and Loop Cut and Slide tools breaks the UVs and Vertex Colors on new vertices, please see the video or the attached .blend file.
Blender_2.91_VetexSlideProblem.mp4

Exact steps for others to reproduce the error

Open the attached file
Press J to cut polygons between selected vertices
Select new vertex
Slide it with G G hotkeys
If you Undo the Vertex Slide, you can slide it again without this problem, but as soon you create a new geometry -- it happens again
Same happens with Loop Cut and Slide tool (Ctrl + R)

Thank you for checking out this bug!
Blender_2.91_VetexSlideProblem.blend

**System Information** Operating system: Windows-10-10.0.18362-SP0 64 Bits Graphics card: GeForce GTX 980/PCIe/SSE2 NVIDIA Corporation 4.5.0 NVIDIA 441.87 **Blender Version** Broken: version: 2.91.0 Alpha, branch: master, commit date: 2020-09-22 12:02, hash: `8d1123ba22` Worked: Blender 2.83 LTS Caused by 93c8955a7 **Short description of error** Vertex Slide and Loop Cut and Slide tools breaks the UVs and Vertex Colors on new vertices, please see the video or the attached .blend file. [Blender_2.91_VetexSlideProblem.mp4](https://archive.blender.org/developer/F8909420/Blender_2.91_VetexSlideProblem.mp4) **Exact steps for others to reproduce the error** 1) Open the attached file 2) Press J to cut polygons between selected vertices 3) Select new vertex 4) Slide it with G G hotkeys 5) If you Undo the Vertex Slide, you can slide it again without this problem, but as soon you create a new geometry -- it happens again 6) Same happens with Loop Cut and Slide tool (Ctrl + R) Thank you for checking out this bug! [Blender_2.91_VetexSlideProblem.blend](https://archive.blender.org/developer/F8909418/Blender_2.91_VetexSlideProblem.blend)

Yan Kansky commented

2020-09-22 17:01:33 +02:00

Added subscriber: @YanKansky

blender-admin commented

2020-09-22 17:01:33 +02:00

#81388 was marked as duplicate of this issue

blender-admin commented

2020-09-22 17:01:33 +02:00

#81364 was marked as duplicate of this issue

Yan Kansky changed title from ~~Vertex Slide tool breaks the UVs and Vertex Colors on new vertices~~ to Vertex Slide and Loop Cut and Slide tools breaks the UVs and Vertex Colors on new vertices

2020-09-22 17:17:11 +02:00

Martijn Versteegh commented

2020-09-22 19:23:06 +02:00

Added subscriber: @Baardaap

Martijn Versteegh commented

2020-09-22 19:23:06 +02:00

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

Martijn Versteegh commented

2020-09-22 19:23:06 +02:00

As I have everything set up for git bisecting between 2.83 and 2.90 I'll do a bisect and find out which commit introduced this.

Martijn Versteegh commented

2020-09-22 21:30:26 +02:00

I'm done bisecting.

The first offending commit is 93c8955a7

Mesh Edit: preserve Custom Normal vectors in topology operators.

I have no clue how this code works, so someone else should look into it.

I'm done bisecting. The first offending commit is 93c8955a7 Mesh Edit: preserve Custom Normal vectors in topology operators. I have no clue how this code works, so someone else should look into it.

Philipp Oeser commented

2020-09-23 11:21:05 +02:00

Added subscriber: @lichtwerk

Philipp Oeser commented

2020-09-23 11:21:05 +02:00

Thx bisecting @Baardaap !

Philipp Oeser changed title from ~~Vertex Slide and Loop Cut and Slide tools breaks the UVs and Vertex Colors on new vertices~~ to Vertex Slide and Loop Cut and Slide tools breaks the UVs and Vertex Colors on new vertices (if CustomSplitNormals are present)

2020-09-23 12:44:08 +02:00

Yan Kansky commented

2020-09-23 14:21:40 +02:00

Can confirm, it happens only when CustomSplitNormals are present!

Philipp Oeser changed title from ~~Vertex Slide and Loop Cut and Slide tools breaks the UVs and Vertex Colors on new vertices (if CustomSplitNormals are present)~~ to Vertex Slide and Loop Cut and Slide tools breaks the UVs and Vertex Colors after topology changes [new or deleted] (if CustomSplitNormals are present)

2020-10-02 09:30:56 +02:00

Philipp Oeser commented

2020-10-02 09:31:53 +02:00

Added subscriber: @Mets