UDK supports up to four bone influences per vertex, allowing for subtle nuances in all your scenes. Full mesh and bone LOD support is also built right into UDK.
The AnimSet Viewer tool will organize your animations and help you browse through your meshes. This gives you the ability to add game-specific notifications at specific points of the animation and allows you to place sockets on bones to be used for attaching objects to the skeleton during gameplay.
Animation is driven by an AnimTree, a tree of animation nodes including:
- Blend controllers, performing an n-way blend between nested animation objects.
- Data-driven controllers, encapsulating motion capture or hand animation data.
- Physics controllers, tying into the rigid body dynamics engine for ragdoll player and NPC animation and physical response to impulses.
- Procedural skeletal controllers, for game features such as having an NPC's head and eyes track a player walking through the level.
- Inverse Kinematics solver for calculating limb pose based on a goal location (e.g. for foot placement).
- Group animations, handling notifications for the whole group. Synchronize all or a subset of them.
- Morph target animation, allowing the control of morph target blend weights from animation data, with support for material control as well. Morph animation can be authored in Maya and morph data can be exported via ActorX. Skeletal animation can now control vertex and material animation, with preview in the AnimSet Viewer.
- Plus, there are no restrictions on the number of animations playing at the same time, number of blends, or post-processing operations.

