Python: bpy.data.meshes.new_from_object() doesn't duplicate Shape Keys #112570

New Issue

Nika Kutsniashvili · 2023-09-19T13:15:16+02:00

2023-09-19 13:15:16 +02:00

System Information
Operating system: Windows-10-10.0.19043-SP0 64 Bits
Graphics card: NVIDIA GeForce GTX 1650/PCIe/SSE2 NVIDIA Corporation 4.5.0 NVIDIA 536.99

Blender Version
Broken: version: 3.6.0, branch: blender-v3.6-release, commit date: 2023-06-27 08:08, hash: c7fc78b81ecb
Worked: (newest version of Blender that worked as expected)

Short description of error
Operator bpy.data.meshes.new_from_object(obj) is duplicating mesh data of the object in it's entirity, with all its attributes, except for shape keys. I assume that is because shape keys are separata data block that are linked to mesh, instead of being part of mesh.

This creates problem for Keymesh add-on and makes it impossible to do stop-motion animation mixing Keymesh and shape keys, which is a requested feature (I am maintaining Keymesh). There are some workarounds, but none efficient.

It would make the operator more complete and assist Keymesh if bpy.data.meshes.new_from_object(obj) operator also assigned shape key data-block that original mesh has to duplicated mesh (or duplicated it and assigned duplicated one). That would be expected and intuitive behavior. Especially since assigning shape keys to meshes isn't really supported in python.

**System Information** Operating system: Windows-10-10.0.19043-SP0 64 Bits Graphics card: NVIDIA GeForce GTX 1650/PCIe/SSE2 NVIDIA Corporation 4.5.0 NVIDIA 536.99 **Blender Version** Broken: version: 3.6.0, branch: blender-v3.6-release, commit date: 2023-06-27 08:08, hash: `c7fc78b81ecb` Worked: (newest version of Blender that worked as expected) **Short description of error** Operator `bpy.data.meshes.new_from_object(obj)` is duplicating mesh data of the object in it's entirity, with all its attributes, except for shape keys. I assume that is because shape keys are separata data block that are linked to mesh, instead of being part of mesh. This creates problem for Keymesh add-on and makes it impossible to do stop-motion animation mixing Keymesh and shape keys, which is a requested feature (I am maintaining Keymesh). There are some workarounds, but none efficient. It would make the operator more complete and assist Keymesh if `bpy.data.meshes.new_from_object(obj)` operator also assigned shape key data-block that original mesh has to duplicated mesh (or duplicated it and assigned duplicated one). That would be expected and intuitive behavior. Especially since assigning shape keys to meshes isn't really supported in python.

Nika Kutsniashvili added the

labels 2023-09-19 13:15:17 +02:00

Nika Kutsniashvili changed title from ~~Python: bpy.data.meshes.new_from_object(obj) doesn't duplicate Shape Keys~~ to Python: bpy.data.meshes.new_from_object() doesn't duplicate Shape Keys

2023-09-19 13:30:20 +02:00

Thomas Barlow commented

2023-09-19 14:08:51 +02:00

Looks like a duplicate of #109313.

For non-evaluated mesh Objects that you need to duplicate and maintain shape keys, you should be able to use Mesh.copy() as a workaround.

Looks like a duplicate of #109313. For non-evaluated mesh Objects that you need to duplicate and maintain shape keys, you should be able to use `Mesh.copy()` as a workaround.

Philipp Oeser commented

2023-09-19 15:12:52 +02:00

evaluated objects get their modifiers applied (that includes the current shapekey mix), so that is expected, for non-evaluated objects, this is indeed a duplicate of #109313.

Therefor, will close as a duplicate, please subscribe in #109313 if you want further updates.

evaluated objects get their modifiers applied (that includes the current shapekey mix), so that is expected, for non-evaluated objects, this is indeed a duplicate of #109313. Therefor, will close as a duplicate, please subscribe in #109313 if you want further updates.

Philipp Oeser closed this issue

2023-09-19 15:12:54 +02:00

Blender Bot added

and removed

labels 2023-09-19 15:12:56 +02:00

Philipp Oeser added

Status

Duplicate