Update "3D Inverse Kinematics" demo for Godot 4

[BurntAussieTyre]

Project path:
" \godot-demo-projects-7e9d31\3d\ik "

The project has multiple issues, these are the ones I'm able to notice:

1. The skeleton rig for "godot_battle_bot.dae" appears to be completely and utterly munted. It looks like spaghetti.

2. There are numerous errors in most of the scripts preventing the project from running. I believe all scripts probably have to be updated for GDScript v4.1.

3. Oh, and maybe all model files should be updated/converted to glTF 2.0?

[GeorgeS2019]

#984

[GeorgeS2019]

3D Inverse Kinematics Godot 4 Conversion (Partial)

The demo is not complete and there is no check if it is consistent with the latest implementation of Animation concept introduced in Godot 4.3 and 4.4:

There needs to clearly state that this demo is not working to avoid others wasting time on 3D IK for Godot4