Multiple Armature Actions IK

I’m trying to make a set of animated templates that I can use to make a collection of RPG jobclasses, like in Final Fantasy Tactics or RPG Maker 2003. I’d like to be able to do multiple body types and have them use the same actions, such as walk, run, jump, swing a sword, ride a giant terrestrial bird, etc, but I’m having trouble with the IK pointers.

Basically, the body proportions are different for the different people, i.e, one guy has massive he-man gorilla arms, and another is a petite girl with shorter limbs.


This is sort of ignorable for a simple standing pose like this, but I’m worried about trouble later on with more complication combat animations.

Are there any techniques or blender abilities designed for this? I’m sure there’s an answer out there, but I don’t know what keywords to search for since I’m having trouble explaining it without the picture.

I’ve been thinking about it more. One solution might be to calculate the IK pointers’ positions based on the base of the limb that they are pointing and the proportional distance. For example, body#1’s arm length is 8.0, while body#3’s is 8.7, so it needs to go 8% farther away from the shoulder when its at rest or swinging a sword or whatever.

I guess what I’m saying is that it should calculate the difference in proportion based on the IK pointer’s location relative to the base of the arm, rather than the origin of the armature (which is at the feet). In that case, I think it should work to just create a parent for the IK pointer at the shoulder joint. Hang on, and I’ll check…

Quick and dirty way to do it is to us FK and key frame bone Rotations only. The movement will be identical for different size character so long as bone proportions are kept mostly the same.

I want to avoid doing anything quick and dirty because these will be models that I want to sell to game developers. Also, using FK really gets on my nerves when it comes to fine adjustments.

But in the same vein, maybe I could bake the action first and then apply it to the different proportioned armatures. My concern then is that it will make it harder for developers to add or adjust animations themselves if they need to. This will be irrelevant if they’re using a .dae file, but I know that Unity allows you to use the .blend or .fbx file itself.

In case it helps, let me explain that what I want to do is provide a set of 3D RPG character resources for smaller developers doing mobile, OUYA, Flash/AIR, etc. I’d like to make the resources complete enough that they don’t need any 3D art skills themselves to make a complete game, but I also want to make it possible and hopefully somewhat simple to adjust or add to the models because every game is going to be different. My plan is to start with 4 body types, a semi-androgynous anime young man and young woman (think Grand Chase, Rumble Fighter style) plus an exaggerated he-man and she-ra style. From there, I’ll do each body type as various RPG classes, so Male Knight, Female Knight, Brute Knight, Amazon Knight, Male Wizard, Female Wizard, Brute Wizard, Amazon Wizard, and so forth.

EDIT: Yes, using Bake Action turns IK into FK and it works great. What I’m going to do is use one rig with IK constraints to write the animations with, and then each body gets its own rig without any IK constraints that receives the baked actions.