Performance and optimization
Improve animation runtime cost with focused controller, layer, and curve optimizations.
Read time 2 minutesLast updated a month ago
This page contains some tips to help you obtain the best performance in Unity, covering the animation system and run-time optimizations.
Note
For tips on modeling your character in a 3d application for best performance in Unity, see Modeling characters for optimal performance.
Animation system
Controllers
The Animator doesn't spend time processing when a Controller is not set to it.
Simple animation
Playing a single Animation Clip with no blending can make Unity slower than the legacy animation system. The old system is very direct, sampling the curve and directly writing into the transform. Unity's current animation system has temporary buffers it uses for blending, and there is additional copying of the sampled curve and other data. The current system layout is optimized for animation blending and more complex setups.
Scale curves
Animating scale curves is more expensive than animating translation and rotation curves. To improve performance, avoid scale animations.
Note
This does not apply to constant curves (curves that have the same value for the length of the animation clip). Constant curves are optimized, and are less expensive than normal curves. Constant curves that have the same values as the default scene values do not write to the scene every frame.
Layers
Most of the time Unity is evaluating animations, and keeps the overhead for animation layers and Animation State Machines to the minimum. The cost of adding another layer to the animator, synchronized or not, depends on what animations and blend trees are played by the layer. When the weight of the layer is zero, Unity skips the layer update.
Humanoid vs. Generic animation types
These are tips to help you decide between these types:
- When importing Humanoid animation use an Avatar Mask (class-AvatarMask) to remove IK Goals or finger animation if you don't need them.
- When you use Generic, using root motion is more expensive than not using it. If your animations don't use root motion, make sure that you have not specified a root bone.
Scene-level optimization
There are many optimizations that can be made, some useful tips include:
- Use hashes instead of strings to query the Animator.
- Implement a small AI Layer to control the Animator. You can make it provide simple callbacks for OnStateChange, OnTransitionBegin, and other events.
- Use State Tags to easily match your AI state machine to the Unity state machine.
- Use additional curves to simulate events.
- Use additional curves to mark up your animations; for example, in conjunction with target matching.
Runtime Optimizations
Visibility and updates
Always optimize animations by setting the animator Culling Mode to Cull Completely, and disable the skinned mesh renderer's Update When Offscreen property. This saves Unity from updating animations when the character is not visible.