For Maya users (Max users also), it’s normal to animate geometries with tools such as IK, constraints, driven keys, deformers and blend shapes. These animation tools are quite mature in those professional 3d graphic softwares in the market.
But once you need to export these excellently animated items into a game platform such as Unity, here comes the headache. Even Unity 5 accepts FK animation only.
Since I wanted to keep my animation no matter how, then the only way I found for this case is:
1, Convert the animation driven by deformers into a joint one, by assigning a FK joint to EACH vertex involved. This could be done automatically via MEL scripting in Maya. This step may repeat.
2. Export this fake FK-driven animation into Unity and test its performance.
For Max user, this progress should be less painful because some nice guy has developed a plugin called “in2Unity3D” to export geometry/vertex animation from 3ds Max to Unity.