broken mesh view while using bendy bones with deformed mesh #60034

Closed
opened 2019-01-01 11:36:11 +01:00 by Norbert Krieg · 31 comments

System Information
Operating system: Debian Jessie Standard
Graphics card: GTX 1060

Blender Version
Broken: 2.80, 4d795cee49, blender2.8, 2018-12-31, 15:45

Short description of error
Using bendy bones crash viewport display of deformed mesh, while rendering is ok.
See attached file as an example.

Exact steps for others to reproduce the error
Different actions lead to a broken mesh in the viewport:

  • tab into edit mode and back
  • switch off and on the view of the armature modifier
  • switch from layout to sculpt mode
  • switch off and on subdivision modifier
  • ...

after that the mesh is corrupted in the viewport display. Rendering shows mesh correctly.

Undoing the weird mesh deformation view:

  • selecting the armature, change to pose mode,
  • select another bone
  • r/g/s the selected bone
  • reducing the segments of the bendy bones to 1

brings back the correct deformed mesh in the viewport display.

bendyBonesBug.blend

**System Information** Operating system: Debian Jessie Standard Graphics card: GTX 1060 **Blender Version** Broken: 2.80, 4d795cee4938, blender2.8, 2018-12-31, 15:45 **Short description of error** Using bendy bones crash viewport display of deformed mesh, while rendering is ok. See attached file as an example. **Exact steps for others to reproduce the error** Different actions lead to a broken mesh in the viewport: - tab into edit mode and back - switch off and on the view of the armature modifier - switch from layout to sculpt mode - switch off and on subdivision modifier - ... after that the mesh is corrupted in the viewport display. Rendering shows mesh correctly. Undoing the weird mesh deformation view: - selecting the armature, change to pose mode, - select another bone - r/g/s the selected bone - reducing the segments of the bendy bones to 1 brings back the correct deformed mesh in the viewport display. [bendyBonesBug.blend](https://archive.blender.org/developer/F6138523/bendyBonesBug.blend)
Author

Added subscriber: @nobi08

Added subscriber: @nobi08

Added subscriber: @ZedDB

Added subscriber: @ZedDB

I sadly can not reproduce this error. This is what it looks like on my end no matter if I go in and out of edit more or toggle the modifiers:

bendy.png

Could you try a build from today and see if that helps? https://builder.blender.org/download/

I sadly can not reproduce this error. This is what it looks like on my end no matter if I go in and out of edit more or toggle the modifiers: ![bendy.png](https://archive.blender.org/developer/F6139922/bendy.png) Could you try a build from today and see if that helps? https://builder.blender.org/download/
Author

I tried the build from today and my own compilation with a fresh git pull.
The bug still stays (see attached image) after switching off and on the armature modifier i.e.

No idea, but animate1978 can second that bug: see "vertices influence broken in 2.80 if using basic muscle armature system"

Probably a linux specific problem? Funny thing is, that it's only visible in the viewport, the render is ok.

Unfortunately you can not work with the deformed mesh, nor sculpt it....
bendyBonesBug.png

I tried the build from today and my own compilation with a fresh git pull. The bug still stays (see attached image) after switching off and on the armature modifier i.e. No idea, but animate1978 can second that bug: see ["vertices influence broken in 2.80 if using basic muscle armature system" ](https://github.com/animate1978/MB-Lab/issues/20) Probably a linux specific problem? Funny thing is, that it's only visible in the viewport, the render is ok. Unfortunately you can not work with the deformed mesh, nor sculpt it.... ![bendyBonesBug.png](https://archive.blender.org/developer/F6140121/bendyBonesBug.png)

I'm also on linux (and I build blender from git too) and I do not have this problem. So I guess this rules out it being a linux specific problem.

I do however not have this muscle plugin installed.

Could you build a Debug build and try it out with that? Maybe some asserts will trigger.

I'm also on linux (and I build blender from git too) and I do not have this problem. So I guess this rules out it being a linux specific problem. I do however not have this muscle plugin installed. Could you build a `Debug` build and try it out with that? Maybe some asserts will trigger.
Author

Specifying it a little bit. Open the bendyBonesBug.blend file. Change the rotation of one of the bendy bones to deform the mesh.
Select the mesh.
Then switching off and on the armature modifier results into the reproducable buggy behaviour... strange

Specifying it a little bit. Open the bendyBonesBug.blend file. Change the rotation of one of the bendy bones to deform the mesh. Select the mesh. Then switching off and on the armature modifier results into the reproducable buggy behaviour... strange
Author

I changed to the loaded factory settings with a fresh config directory to reproduce the buggy behaviour, no other addons are installed know.
Same as before.
How to build a debug build? Didn't do that before?

I changed to the loaded factory settings with a fresh config directory to reproduce the buggy behaviour, no other addons are installed know. Same as before. How to build a debug build? Didn't do that before?

Still can't reproduce this even if I pose the armature a bit first. :c

Here is a short guide how to change cmake settings: https://wiki.blender.org/wiki/Building_Blender/Linux/Generic_Distro#3._Compile_Blender_with_CMake

You want to change CMAKE_BUILD_TYPE to Debug and recompile blender.

Still can't reproduce this even if I pose the armature a bit first. :c Here is a short guide how to change cmake settings: https://wiki.blender.org/wiki/Building_Blender/Linux/Generic_Distro#3._Compile_Blender_with_CMake You want to change `CMAKE_BUILD_TYPE` to `Debug` and recompile blender.

BTW, could you try and see if the official builds has this problem for you?

BTW, could you try and see if the official builds has this problem for you?
Author

I tried the official builds (beta from https://builder.blender.org/download/) - same behaviour.
Build blender as Debug build - same behaviour, no warnings/errors during run with "blender -d".

This buggy behaviour is reproducable.
Why is it only with bendy bones if segments are >1?
Why is it only visible in the viewport?
Why can it be readjusted if armature is touched (edit mode/rotation i.e)?
Why is it not visible in the render?

I tried the official builds (beta from https://builder.blender.org/download/) - same behaviour. Build blender as Debug build - same behaviour, no warnings/errors during run with "blender -d". This buggy behaviour is reproducable. Why is it only with bendy bones if segments are >1? Why is it only visible in the viewport? Why can it be readjusted if armature is touched (edit mode/rotation i.e)? Why is it not visible in the render?

Added subscriber: @WilliamReynish

Added subscriber: @WilliamReynish

@WilliamReynish can you reproduce this?

@WilliamReynish can you reproduce this?

I cannot reproduce this either on Mac.

There's a chance it could be related to a driver issue, but hard to tell.

I cannot reproduce this either on Mac. There's a chance it could be related to a driver issue, but hard to tell.

Added subscriber: @fclem

Added subscriber: @fclem

After messing around for a while longer I was able to make it glitch:

Screenshot 2019-01-01 at 20.59.35.png

Screenshot 2019-01-01 at 20.59.07.png

No idea what is causing this. @fclem ?

After messing around for a while longer I was able to make it glitch: ![Screenshot 2019-01-01 at 20.59.35.png](https://archive.blender.org/developer/F6142607/Screenshot_2019-01-01_at_20.59.35.png) ![Screenshot 2019-01-01 at 20.59.07.png](https://archive.blender.org/developer/F6142610/Screenshot_2019-01-01_at_20.59.07.png) No idea what is causing this. @fclem ?
Author

Funny thing is, I can get back the regular mesh, if I am in pose mode and choose another bone or just type R and ESC...
Why should a graphic driver react on the latter one?
Strange...

Funny thing is, I can get back the regular mesh, if I am in pose mode and choose another bone or just type R and ESC... Why should a graphic driver react on the latter one? Strange...
Author

Some more examination brings the following result:
depending on the armature's mode after deformation, the effect occurs or not.

If the armature is still in pose mode after rotating a bone, there is no mesh glitching.
If the armature is not any more in pose mode after rotating a bone, selecting the mesh and tabbing into edit mode and out there is the mesh glitching. (same with switching off/on any modifier of the mesh).

This explains, why probably the bug is not visible for some, and was visible for billreynish only after some fiddling...
@zeddb : if you don't mind, could you test it again while setting the armature into object mode after deforming the mesh , please?

Some more examination brings the following result: depending on the armature's mode after deformation, the effect occurs or not. If the armature is still in pose mode after rotating a bone, there is no mesh glitching. If the armature is not any more in pose mode after rotating a bone, selecting the mesh and tabbing into edit mode and out there is the mesh glitching. (same with switching off/on any modifier of the mesh). This explains, why probably the bug is not visible for some, and was visible for [billreynish ](https://developer.blender.org/p/billreynish/) only after some fiddling... @[zeddb ](https://developer.blender.org/p/zeddb/) : if you don't mind, could you test it again while setting the armature into object mode after deforming the mesh , please?

Added subscriber: @Foaly

Added subscriber: @Foaly

I can reproduce.

Windows 10 64 bit
Nvidia GTX 750 Ti
2.80.0-git.c97c76c01c1d

Exact Steps

  • Select Armature
  • Enter Pose Mode
  • Rotate one bone
  • Enter Object Mode
  • Select Mesh
  • Turn Armature Modifier On / Off repeatedly. Usually happens after 3 to 10 tries.

The mesh is either just deformed slightly, crunched towards the origin or stretched into the infinity.
Sometimes only part of the mesh is affected, while the rest looks okay.

If Edit Mode is entered while the glitch is visible, the effect will persist into edit mode. The dots for the vertices are drawn in the spots where they are actually displayed.
It also persists after applying the modifiers.

I can reproduce. Windows 10 64 bit Nvidia GTX 750 Ti 2.80.0-git.c97c76c01c1d **Exact Steps** * Select Armature * Enter Pose Mode * Rotate one bone * Enter Object Mode * Select Mesh * Turn Armature Modifier On / Off repeatedly. Usually happens after 3 to 10 tries. The mesh is either just deformed slightly, crunched towards the origin or stretched into the infinity. Sometimes only part of the mesh is affected, while the rest looks okay. If Edit Mode is entered while the glitch is visible, the effect will persist into edit mode. The dots for the vertices are drawn in the spots where they are actually displayed. It also persists after applying the modifiers.
Campbell Barton was assigned by Sebastian Parborg 2019-01-05 19:33:50 +01:00

Added subscriber: @ideasman42

Added subscriber: @ideasman42

I'm unsure where this problem lies @ideasman42 so feel free to reassign. I could finally reproduce the issue with the instructions above.
No asserts were triggered with the debug build...

I'm unsure where this problem lies @ideasman42 so feel free to reassign. I could finally reproduce the issue with the instructions above. No asserts were triggered with the debug build...

I can reproduce but I'm pretty sure it is a problem with the modifier and not the display.

I can reproduce but I'm pretty sure it is a problem with the modifier and not the display.

Added subscriber: @animate1978

Added subscriber: @animate1978
Author

Changed status from 'Open' to: 'Resolved'

Changed status from 'Open' to: 'Resolved'
Author

Seems to work know.
Thanks to ...??

Seems to work know. Thanks to ...??

Changed status from 'Resolved' to: 'Open'

Changed status from 'Resolved' to: 'Open'

This is in fact not solved.
I can still reproduce with the newest 2.80 beta build. 98f00a3eb5

This is in fact not solved. I can still reproduce with the newest 2.80 beta build. 98f00a3eb526

Added subscriber: @angavrilov

Added subscriber: @angavrilov
Campbell Barton was unassigned by Alexander Gavrilov 2019-05-07 10:08:59 +02:00
Alexander Gavrilov self-assigned this 2019-05-07 10:08:59 +02:00

I can only reproduce it with the described steps if I disable the fix for #63332, so unless somebody can confirm this still exists, this bug would be closed.

I can only reproduce it with the described steps if I disable the fix for #63332, so unless somebody can confirm this still exists, this bug would be closed.

Changed status from 'Open' to: 'Resolved'

Changed status from 'Open' to: 'Resolved'

Can't seem to reproduce this either now. So I'll close this until someone states otherwise.

Can't seem to reproduce this either now. So I'll close this until someone states otherwise.
Sign in to join this conversation.
No Label
Interest
Alembic
Interest
Animation & Rigging
Interest
Asset Browser
Interest
Asset Browser Project Overview
Interest
Audio
Interest
Automated Testing
Interest
Blender Asset Bundle
Interest
BlendFile
Interest
Collada
Interest
Compatibility
Interest
Compositing
Interest
Core
Interest
Cycles
Interest
Dependency Graph
Interest
Development Management
Interest
EEVEE
Interest
EEVEE & Viewport
Interest
Freestyle
Interest
Geometry Nodes
Interest
Grease Pencil
Interest
ID Management
Interest
Images & Movies
Interest
Import Export
Interest
Line Art
Interest
Masking
Interest
Metal
Interest
Modeling
Interest
Modifiers
Interest
Motion Tracking
Interest
Nodes & Physics
Interest
OpenGL
Interest
Overlay
Interest
Overrides
Interest
Performance
Interest
Physics
Interest
Pipeline, Assets & IO
Interest
Platforms, Builds & Tests
Interest
Python API
Interest
Render & Cycles
Interest
Render Pipeline
Interest
Sculpt, Paint & Texture
Interest
Text Editor
Interest
Translations
Interest
Triaging
Interest
Undo
Interest
USD
Interest
User Interface
Interest
UV Editing
Interest
VFX & Video
Interest
Video Sequencer
Interest
Virtual Reality
Interest
Vulkan
Interest
Wayland
Interest
Workbench
Interest: X11
Legacy
Blender 2.8 Project
Legacy
Milestone 1: Basic, Local Asset Browser
Legacy
OpenGL Error
Meta
Good First Issue
Meta
Papercut
Meta
Retrospective
Meta
Security
Module
Animation & Rigging
Module
Core
Module
Development Management
Module
EEVEE & Viewport
Module
Grease Pencil
Module
Modeling
Module
Nodes & Physics
Module
Pipeline, Assets & IO
Module
Platforms, Builds & Tests
Module
Python API
Module
Render & Cycles
Module
Sculpt, Paint & Texture
Module
Triaging
Module
User Interface
Module
VFX & Video
Platform
FreeBSD
Platform
Linux
Platform
macOS
Platform
Windows
Priority
High
Priority
Low
Priority
Normal
Priority
Unbreak Now!
Status
Archived
Status
Confirmed
Status
Duplicate
Status
Needs Info from Developers
Status
Needs Information from User
Status
Needs Triage
Status
Resolved
Type
Bug
Type
Design
Type
Known Issue
Type
Patch
Type
Report
Type
To Do
No Milestone
No project
7 Participants
Notifications
Due Date
The due date is invalid or out of range. Please use the format 'yyyy-mm-dd'.

No due date set.

Dependencies

No dependencies set.

Reference: blender/blender#60034
No description provided.