How does an Avatar come to life? What sorcery must be done to make things that look so simple actually work?
That my friend is the power of Unity Animators, the driving heartbeat of every Avatar that exists in VRChat! We use Animator Controllers to organize, sort, and determine how an Avatar behaves and looks at runtime. In this section, we'll be looking at the many different Layers that allows an Avatar to come to life!
By default, VRChat uses 5 Playable Layers. Each of them serves their own purpose. If your Avatar is set to use any of the defaults, then it will always play the default Animator Controller for that specific Layer.
In most cases, you will not need to make each one separately all 5 Layers at once. Most likely, you'll only use 2. I'll explain more what are most commonly modified further below. But either way, it is pretty important to get an understanding of what each of them does and how it will affect your Avatar.
All example Animator Controllers and it's sister .anim files that VRChat uses are included in all versions of the VRChat SDK for Avatars 3.0. To find them in projects created using Creator Companion, they will all be located in: Packages/VRChat SDK - Avatars/Samples/AV3 Demo Assets/Animation.Note that Packages/VRChat SDK - Avatars folder may show as com.vrchat.avatars if viewing it's files through Windows Explorer.
Packages/VRChat SDK - Avatars/Samples/AV3 Demo Assets/Animation
Packages/VRChat SDK - Avatars
Default Animator Controller: vrc_AvatarV3LocomotionLayer.controller
Commonly referred to as "Locomotion," this Layer is the sole heartbeat behind all kinds of Avatar Movement! This includes things such as Walking, Running, Falling, Crouching, Sitting, and Jumping! If you ever wanted to know where all of that movement happens from, this is the Controller that is responsible for all of that!
In many cases, this layer is rarely edited by the end-user because this Layer is very complex! It contains a vast amount of Blendtrees, Transitions, and animation states that reference to Humanoid Animations. These Humanoid .anim files are far different than any kind of Animation! They specifically control the IK (aka Inverse-Kinematics) of a Humanoid Avatar Rig.
Be extremely careful when editing Humanoid Animations! Any mistake you make could end up creating wild Locomotion behavior with your Avatar! We recommend copying the default Animations so that the original files aren't affected.
Humanoid Animations are VERY HARD to edit on your own without the right plugins! You'll see why if you attempt to look at the keyframes of those .anim files.Use a plugin such as Muscle Animation Editor or Very Animation to edit them, as they are designed to create and/or edit Humanoid Animations. They can be found on the Unity Asset Store.
Default Animator Controller: None (User Dependent)
None (User Dependent)
Additive is a special layer. It is added on-top of the Base controller for animations that should "add-on" in addition to an existing Humanoid Bone affected by IK. This can be used for things such as a "breathing" animation that uses Bones to make that happen.
This Layer is rarely used in most cases.
Animations in Additive SHOULD ONLY AFFECT Humanoid Bones that are driven by IK! If you have non-humanoid bones such as Ears or a Tail, use the Gesture Controller! More info on Gesture in Section 3.1.3.
Default Animator Controller: vrc_AvatarV3HandsLayer.controller
The Gesture Layer is used for Animations that require to act on individual body parts while still playing the underlying Animations for the rest of the body
This is an important layer. Gesture is used to determine how Fingers on an Avatar's Hand should animate depending on which Hand Gesture the user is attempting to pose. They would be either Fist, Open, Point, Peace, Rock N' Roll, Finger Gun, or Thumbs Up.
If you have an Avatar that will have Idle or Puppet Animations on non-Humanoid Bones such as Ears or a Tail, use the Gesture Layer! In addition, it is highly advised that any kind of non-Humanoid Bone that will have it's Transforms animated to go into the Gesture Layer!
The first 3 Layers are mainly important. They require the usage of Masking in order to direct the Animations to affect a certain part of your Avatar. For VRChat, they default Masks are located in Packages/VRChat SDK - Avatars/Samples/AV3 Demo Assets/Animation/Masks.
Packages/VRChat SDK - Avatars/Samples/AV3 Demo Assets/Animation/Masks
Here are the Masking Requirements to follow for the first 3 Layers of the Gesture Controller:
To use Hand Gestures in VRChat using an Oculus or Vive Controller, please refer to the image chart shown on VRChat's Documentation here. Valve Index Controllers will most likely at times never play the finger animations as those are overridden by it's native Finger Tracking.
Default Animator Controller: vrc_AvatarV3ActionLayer.controller
The Action Layer is for Humanoid Animations that should override all other Layers, for times when you would want to play an "Animated Emote."
If you have a Dance Emote, this is where you would want to put it!
Before adding your own Animations to Action, make sure to use the VRC Playable Layer Control component! Since the Action Layer is Weighted to 0 by Default, you need to override it's Weight before an Animation is played!In addition, you will need to make use of the VRC Animator Tracking Control as well. This animation state component allows you to filter out any of your own movements before and after an Animation plays!
VRC Playable Layer Control
VRC Animator Tracking Control
The FX is a special layer! What's so unique about this Layer is that everything in the FX is copied over! In other words, Animations that DO NOT affect Transforms whatsoever shall be put into this Layer!
The FX is the most common Layer to be edited by the end-user and for good reason. This is where the majority of the swag that you add to your Avatar should be animated from! Want to put an Animation that changes a Material? Put it in the FX! What about Object Toggles? Yes! Put it in the FX! Blendshape Animations? Absolutely! Wanna enter the battlefield with that cool Lightsaber you got for Christmas that can be thrown like a true Jedi? This is where you put those Animations in!
To put it simply, this is the Layer that your Object Toggles and other magical things that would impress Gandalf should go to! Many of the magical things that users show off to "wow" the whole audience were primarily Animated in the FX! If you ever watched a Tutorial somewhere on how to make a simple object Toggle, it is super often to see the FX being used to create those Toggles!
On some Avatars, you may also see the first few Layers to be labeled similarly to how Gesture labels them. Things like Left Hand, Right Hand, or Both Hands. The Animations used on these are NOT like the ones seen in Gesture! In the FX, they are used for Facial Expressions that are driven by Blendshapes on a Skinned Mesh, for example. They also never use a Mask. So if you want to have your Avatar have Facial Emotions triggered by your Hand Gestures, this is where you should animate them!
Try to avoid transitioning from "Any State" for your Facial Expressions driven by your Hand Gestures and instead use a transition pattern such as Entry -> Idle -> [your Expression here] -> Exit, for example. This is because any Condition that is from an "Any State" is checked for every frame, which can be expensive to your CPU compared to a normal transition pattern.
Entry -> Idle -> [your Expression here] -> Exit
DO NOT USE MASKS ANYWHERE IN THE FX! As of the latest VRChat SDK versions, any Mask used in the FX will greatly conflict (and possibly break) any Finger Animation used with the Gesture Controller! This is especially important to know as it mainly affects users with Oculus or Vive Controllers!