public void makeLayer(String name, AnimationMask mask) {
        AnimLayer l = new AnimLayer(name, mask);
        layers.put(name, l);
    }
Add a layer to this composer.

@param name the desired name for the new layer
@param mask the desired mask for the new layer (alias created)
jme3-core/src/main/java/com/jme3/anim/AnimComposer.java