Animation Graph
Node-based runtime animation evaluation
Also known as: AnimGraph · Animation Blueprint
Definition
An animation graph is the per-frame node graph that evaluates pose data and produces a final skeleton pose ready for rendering. Inputs are state machines, blend spaces, and live data (IK targets, lookAt); outputs are bone transforms. Unreal’s AnimGraph and Unity’s Animator Controller graph are the two most common implementations. Most live animation logic — additive layers, IK, foot placement — lives in this graph rather than in the source clips.
In production
Unreal's AnimGraph evaluates every frame from a "Result" pose node backward, pulling from state machines, blend spaces, and Control Rig nodes, then layering IK and foot-placement logic on top before handing the final pose to the skeletal mesh component. Unity's Animator Controller graph is comparatively simpler by default, but a Playable Graph built through the Animation Rigging package lets programmers inject procedural layers — look-at constraints, aim offsets — much like Unreal's AnimGraph does natively. A common technical-animator task is adding a "hand IK" layer so a character's grip stays locked to a weapon's grip socket regardless of which locomotion clip is playing underneath, which requires blending the IK node in after the base pose rather than before it. Because the graph runs every frame per-character, expensive nodes (full-body IK solves, multiple blend spaces) are a real CPU cost on crowds, which is why cheaper LOD versions of the AnimGraph are often set up for background characters.
