Regression: Weight Painting doesn't work with Mirror and Armature modifier #100862

New Issue

Pavel Duong · 2022-09-06T21:55:05+02:00

Pavel Duong commented

2022-09-06 21:55:05 +02:00

System Information
Operating system: Arch Linux
Graphics card: Intel UHD 620

Blender Version
Broken: 3.4
Worked: 3.3
Caused by 9823a8f72b
Short description of error

Attempting to weight paint on mirrored mesh with armature on it will only work when painting over where the mesh was in its undeformed state.

Exact steps for others to reproduce the error

(Skip to step 4 if using the following file)

Create a cube, add a mirror modifier to it (you can offset them in mesh, so they don't intersect)
Create an single bone armature and parent the Cube to it using Automatic Weights
Enter pose mode in the armature and move the bone
Exit pose mode, enter Weight Painting mode of the Cube
Attempting to change weights in the posed location will not work, however it will change if you're drawing over the area where the undeformed mesh would be.
broken_weight_painting.blend

74f983738ab4 (working) 0ff920b77779 (broken)

working_weight.mp4 broken_weight.mp4

**System Information** Operating system: Arch Linux Graphics card: Intel UHD 620 **Blender Version** Broken: 3.4 Worked: 3.3 Caused by 9823a8f72b **Short description of error** Attempting to weight paint on mirrored mesh with armature on it will only work when painting over where the mesh was in its undeformed state. **Exact steps for others to reproduce the error** *(Skip to step 4 if using the following file)* 1. Create a cube, add a mirror modifier to it (you can offset them in mesh, so they don't intersect) 2. Create an single bone armature and parent the Cube to it using Automatic Weights 3. Enter pose mode in the armature and move the bone 4. Exit pose mode, enter Weight Painting mode of the Cube 5. Attempting to change weights in the posed location will not work, however it will change if you're drawing over the area where the undeformed mesh would be. [broken_weight_painting.blend](https://archive.blender.org/developer/F13463386/broken_weight_painting.blend) |`74f983738ab4` (working)|`0ff920b77779` (broken)| | -- | -- | |[working_weight.mp4](https://archive.blender.org/developer/F13463393/working_weight.mp4)|[broken_weight.mp4](https://archive.blender.org/developer/F13463394/broken_weight.mp4)|

Pavel Duong commented

2022-09-06 21:55:05 +02:00

Added subscriber: @vignette