Keep an object's origin at 0 during an animation?

Question

This is difficult for me to explain, unfortunately.. Please bear with me.

I would like to use simulated physics on an object and bake the physics into keyframes for that object, which i have done. But is there a way for me to keep the object's XYZ locations and rotations in object mode at 0 while only the mesh moves?

I'm basically trying to create something like, for example, a model of a brick wall that breaks apart to be used in a video game to give the illusion of real time physics in that game. I figured I could simulate physics for the model and bake to keyframes, and then use those keyframes on the bones that the model will be rigged to. But I need everything's XYZ at 0 in object mode. But I'm a newbie so I don't know how to accomplish this.

So to simplify the question as much as I can: how can I transfer the keyframes from the simulated physics from the object to the bone but keep their origins at 0.

Answer 1

For a video game you don't want to do that. Shape key animations are very expensive and hard to transfer over. Plus, the pieces would not interact with the rest of the game world.

You most likely want to simulate the physics for the pieces in real time in the actual game engine. Often this type of things are made with an intact version of the wall and after the impact happens, the object is removed and the physics-simulated pieces are instantiated.

Or if you want a non-interactive version you could make a rig for the pieces and bake the simulation on the rig in Blender, then export the object with meshes and animation. Considering how advanced and efficient the physics simulation capabilities of even free and indie game engines are today, this is becoming an increasingly obsolete solution.

Answer 2

Yes, shape keys allow you to modify your mesh in a very controlled way, and the animation ability of these things are amazing.

As far as manipulating bones this way, you may be needing to look in the pose library slant of things, but admittedly rigging is not my strong point, so others in this community will still be able to help you, and correct my miss-speakings if necessary.

If you are thinking of transferring keyframes, I believe that you are going to end up looking at copying keyframes over to the Dopesheet >> Action Editor Under a new action, or just using the pose library actions.

Once you have all of your actions mapped over, you will be able to sequence those actions within the NLA editor.

Now the bigger question is how to take your bone movements, and have them affect your shape keys.

The bigger answer is probably Drivers &/OR Constraints.

All this being said, I believe that I am pointing you in a valid (if not good) direction, but I don't believe that this particular question is granular enough to be accepted here because of how big the scope would have to be to cover all of these topics, and specifically your project. So if someone doesn't come along and answer this one very effectively to validly replace my answer, please read up on the advice of topics (marked in BOLD), and ask smaller questions as you navigate through the learning curve of how to accomplish your workflows.

AND / OR

Modify your answer to demonstrate more specifically what you are trying to get done. Maybe even include your blend file, or some animation that portrays your specific needs.