Parenting a Lattice to an Armature using Automatic Weights doesn't work #60791

New Issue

William Reynish · 2019-01-23T12:01:26+01:00

William Reynish commented

2019-01-23 12:01:26 +01:00

System Information
Operating system: macOS 10.14
Graphics card: AMD Radeon R9 M395X 4096 MB

Blender Version
Broken: Blender 2.80 beta 2019-01-23

Short description of error
When parenting a lattice object to an armature using the Automatic Weights feature, no weights are assigned - it doesn't work.

Exact steps for others to reproduce the error

Lattice_Automatic_Weights_bug.blend

Open the blend file here.
Select the Lattice, then the Armature.
Press Ctrl-P and select Automatic Weights.
Move the bones around and you'll see the lattice doesn't move

You can also enter edit mode and see that all the weights are set to 0. The deformation does work if you manually add weights, but the Automatic Weights feature fails here.

**System Information** Operating system: macOS 10.14 Graphics card: AMD Radeon R9 M395X 4096 MB **Blender Version** Broken: Blender 2.80 beta 2019-01-23 **Short description of error** When parenting a lattice object to an armature using the Automatic Weights feature, no weights are assigned - it doesn't work. **Exact steps for others to reproduce the error** [Lattice_Automatic_Weights_bug.blend](https://archive.blender.org/developer/F6378027/Lattice_Automatic_Weights_bug.blend) - Open the blend file here. - Select the Lattice, then the Armature. - Press Ctrl-P and select Automatic Weights. - Move the bones around and you'll see the lattice doesn't move You can also enter edit mode and see that all the weights are set to 0. The deformation does work if you manually add weights, but the Automatic Weights feature fails here.

William Reynish commented

2019-01-23 12:01:26 +01:00

Added subscriber: @WilliamReynish

William Reynish commented

2019-01-23 12:14:06 +01:00

To be fair, this also didn't work in 2.79. It could be a missing feature, but in that case we should not display the Automatic Weights feature as an option for lattices.

The nicest thing of course would be if we could support this and make it work.

Lattices are used a lot for rigging - especially with GP objects where you can't practically weight each keyframe, Lattices are a better way to deform them using lattices as an intermediary between the GP object and bones.

To be fair, this also didn't work in 2.79. It could be a missing feature, but in that case we should not display the Automatic Weights feature as an option for lattices. The nicest thing of course would be if we could support this and make it work. Lattices are used a lot for rigging - especially with GP objects where you can't practically weight each keyframe, Lattices are a better way to deform them using lattices as an intermediary between the GP object and bones.

Jacques Lucke commented

2019-01-23 12:22:40 +01:00

Added subscriber: @JacquesLucke

Jacques Lucke commented

2019-01-23 12:22:40 +01:00

Yeah, I'm checking the code right now and was wondering why this case is completely missing haha
Not sure how hard it is to compute automatic weights, checking that right now.

Yeah, I'm checking the code right now and was wondering why this case is completely missing haha Not sure how hard it is to compute automatic weights, checking that right now.

Jacques Lucke commented

2019-01-23 12:36:37 +01:00

Setting to "needs triage" again because I'm not sure if we consider this a bug.
It's certainly possible to implement this feature though.

At least the UI should be changed maybe so that only options that actually do something are visible.

Setting to "needs triage" again because I'm not sure if we consider this a bug. It's certainly possible to implement this feature though. At least the UI should be changed maybe so that only options that actually do something are visible.

Brecht Van Lommel commented

2019-01-23 12:59:01 +01:00

Added subscriber: @brecht