Bake animations from imported models to different ones.

Zeftax

I'm planning a dynamic weapon system (a handful of weapon "types" with unique animations (shortsword, axe, zweihander, ...), and multiple models for each type (broken sword, nice sword, mythical, whatever)). I think a way to do this is by having the hand and the sword models separate (so ignore the zweihander now I guess 😃, trying to get my footing in 3d so just one hand for now). I have a special "weapon target" bone in my hand model, that carries all the animations, and then I just import both the sword and the hand into redot and I want to place the sword where the sword target bone is. I can currently do that just fine by running the following code on the hand skeleton update:

# Called every time the arm skeleton finishes an update
func _on_skeleton_updated():
	# Find the weapon target bone
	var palmId : int = $ViewPivot/arm/Armature/Skeleton3D.find_bone("weapontarget");
	# Get the transform of the bone in relation to the skeleton.
	var palmPos : Transform3D = $ViewPivot/arm/Armature/Skeleton3D.get_bone_global_pose(palmId);
	# Transform the pose to view pivot space (all 0-trans between skeleton origin and arm)
	# And apply the transform to the sword
	$ViewPivot/sword.transform= $ViewPivot/arm.transform * palmPos;

I know I can get the palmId just once and store it in a global variable, but even then, calling this on every frame seems wasteful. What I think would be the best approach is if the sword could play the arm animations (and be 100% influenced by the weapon target bone). I think I could theoretically achieve this with post import scripts, but not really (if the import order can't stay the same). Another option would be to do this linking when launching the game, but tbh. at that point it seems like running the little script on each frame would be better...
All those options just feel like I am missing some more elegant inbuilt way to do this, is there one or is my goal just too weird?
The weapon target bone on the model

The effect of the script places the sword in my hand

bitshift-r

I think you're looking for BoneAttachment3D. That can be used to attach a weapon to your skeleton, I believe doing essentially what your custom code is doing.

I'm not exactly sure what you're asking about weapon animations, but this is my workflow for loading animations at runtime (as opposed to import time):

Animate your skeleton in Blender (or wherever) for the new weapon
Import into a temporary Redot project (this is just my workflow, feel free to import into your main game project of course)
Export only the new weapon's animation as its own resource file (from the animation player click the Animation button and then Manager Animations...)
Delete the temporary Redot project
Load the animation resource at runtime (AnimationPlayer.get_animation_library(...).add_animation(...)

Now you will have an animation that you can pair with a weapon mesh, allowing you to add new weapons with unique animations at any stage of development.

This should work as long as you animate on the same skeleton that you are using for your game.

Zeftax

bitshift-r Thanks! The resource workflow is unnecessary in my case, I think. But I just reparented the weapon to a BoneAttachment and set it to follow the weapontarget bone and it works exactly as I wanted.