Expressions
An expression is a set of parameter changes laid over whatever pose the model is in: a smile, angry brows, a blush. They are saved as Cubism exp3.json files, which VTube Studio and other runtimes switch on and off.
The Expression palette
Open Window > Expression. In the Animation workspace it is a tab beside the Timeline. The palette lists the model's expressions, one row each.
| + | New empty expression |
| Duplicate | a copy of the picked expression |
| Delete | removes it |
| Name | what the expression is called, and the name of its file |
| Set from pose | fills the expression from the pose: every parameter moved off its default becomes an Add of the difference |
Pick an expression to edit it.
Parameters
Add parameter… opens the Add Parameter popup: Filter parameters narrows the list, a slider over the parameter's range sets the value (or type it exactly), and Add, Multiply or Overwrite says how it combines with the pose. Parameters the expression already has are greyed out with Already in this expression.
| Blend | |
|---|---|
| Add | the value is added to the parameter |
| Multiply | the parameter is multiplied by the value |
| Overwrite | the parameter is set to the value |
Each row of the expression then has its Value to drag, its Blend to change, and Remove.
Fades
Fade in and Fade out set how long the expression takes to come and go, in seconds. Each has a tick box: ticked, it starts at one second; unticked, the time is left to the player, which uses one second.
Preview
The eye (Preview: lay the expression over the pose) shows the picked expression on the canvas over the current pose. Changing a value turns it on, and the parameter in the Add Parameter popup shows before it is added.
Exporting
The moc3 export writes each expression to expressions/<name>.exp3.json and lists it in the model3.json, when exp3.json for each expression is ticked. Two expressions with the same name get _2 and so on. Expressions in a model3 bundle you open come in as expressions. The Render window can lay an expression over an animation while it renders.
See Your first expression for a walk through.