I suddenly have the feeling that I have absolutely no idea how to implement invisible objects/bones.
Right now, I use hardware instancing to store the world matrix of every bone in a vertex buffer, and then send them all to the pipeline. But when dealing with frustum culling, or having them set to invisible by my simulation for other reasons, means that some of them will be randomly invisible.
Does this mean I effectively need to re-fill the buffer from scratch every frame with only the visible unit's matrices? This seems to me like it would involve a lot of wasted bandwidth.