In this section, you create a blend shape deformer to control the smile on baseFace (base object) using the smilingFace (target object). A blend shape deformer is ideal for facial animation, where you need a number of facial positions to be readily available for use in an animation sequence. With a blend shape deformer, you can set up a character’s face to blend between a smile, frown, smirk, and so on.
The smilingFace (the first selection) is called the target object, while baseFace (the second selection) is called the base object. The objective of a blend shape operation is to morph the base shape into the target shape.
Note that you can click the Key button below the slider to set an animation key for the shape of the face at the current frame. By setting a few keys with different slider values at different points in the timeline, you can animate from the neutral expression to a full or partial smile or vice versa.
When you key the shape, Maya applies the key to the blendShape node that was created when you selected . If you need to select the blendShape node, for instance, so you can see or delete the keys in the Time Slider, click the Select button in the Blend Shape editor.