Blender model shape keys only work with no modifier import and double click import settings not applying

[Cigam-HFden]

Godot version

v4.1.1.stable.official [bd6af8e]

System information

Godot v4.1.1.stable - Windows 10.0.22621 - Vulkan (Forward+) - dedicated NVIDIA GeForce RTX 3070 Ti Laptop GPU (NVIDIA; 31.0.15.3734) - 12th Gen Intel(R) Core(TM) i9-12900H (20 Threads)

Issue description

I have been working on a project that has various models that have mirror, subdivision and other modifiers in blender. The models themselves also have various shape keys. However in godot it does not import the shape keys unless I turn off the modifiers. I know there is various work being done on shape keys, but also noticed a weird issue on the import screen.

When double clicking on the import screen I can turn it from all modifiers to no modifiers, but when double clicking to go from no to all, it does not work. I have to goto the import tab to get the no to all setting to apply on reimport. I am using blender 3.6.2 as well if that makes any difference.

Steps to reproduce

Here is a video showing the issue:

2023-09-12.16-47-11.mp4

Minimal reproduction project

Here is my testshapekeys project from the video:

testshapekeys.zip

[fire]

As far as I know blender's modifiers cannot bake to blend shapes. @julienduroure

https://blender.stackexchange.com/questions/155930/cant-apply-modifiers-with-shapekeys-on-blender-2-8

it's a blender limitation

see third party script

see also https://github.com/V-Sekai/V-Sekai.blender-game-tools/tree/main/addons/ApplyModifierForObjectWithShapeKeys

[Cigam-HFden]

Good to know about having to apply them. I wonder though, would something like that script be possible for godot to do on import? Then it would have the modifiers applied and have the shape keys, but would not require applying them in the blend file. That way the blend file can maintain the edit-ability, while still being usable in godot with the shape keys.

[Cigam-HFden]

I would assume it is a bug and not documentation with the import tab working to change the modifier but the double click window not, but that is up to y'all.

[TokageItLab]

This is definitely a problem on the blender side, not a bug in godot.

[julienduroure]

As far as I know blender's modifiers cannot bake to blend shapes

I confirm. This is not a bug in Blender, but a known limitation. Not on glTF exporter side, but in Blender core side.

[Cigam-HFden]

I guess no one really watched the video. I accept and understand now that the blender shape keys are limited and categorized as modifiers, which make them have issues on importing. Shape keys at first I thought was an issue, but understand that shape keys are a blender specific issue. The shape key does odd even in godot where my to sphere shape key is only partly rounding the cube not doing the full shape key, but that is not the part of this that I think is the bigger bug.

The "bug" I am referring to is the import window process. In which I had double clicked on the .blend file in godot to change the import settings. Specifically I changed it from all modifiers to no modifiers. But trying to change it from no to all in that double click window does not work. I have to goto the import tab to get it to go from no to all. I would have thought that either would have worked since they are both import screens.

So that godot window/tab import bug is the main one I am concerned about as the bug report (as mentioned in title, text, and video). The shape key not fully transforming is an issue too, but not a big one currently.

[Cigam-HFden]

I was testing a different scene the shape key not working in the video, and figured out that if the "Generate LODs" is on for import, then it makes it a low res mesh with wonky shape keys. However if you turn that setting off the shape keys and model look exactly like they do in blender. Meaning my cube to sphere shape key looks like a sphere now. I can make a separate bug report for that if desired. To be different than the import screen bug in this one.

[Cigam-HFden]

In godot 4.2 beta 4 the double click import dialog bug, especially with the no modifier option to all is fixed.

The LOD generation still breaks the blend shapes, but that is the only issue currently with this.

[fire]

See LOD generation breaking animated meshes bug here #84479