The tongue is very important when animating your character, helping to create good facial expressions which are fundamental when animating dialogues. Although subtle in essence, it makes a big difference when animating your character while it's saying things such as "hello".

Not only when speaking, but what if your character wants to have an ice cream?

How to do it...

1. Open the file 004-Tongue.blend from this book's support files. You'll find our character's face rigged with shape keys, lattices, and a jaw controller as the result of previous recipes.

   If you move the Jaw controller down, you'll see that there's a mesh called Otto_Tongue inside the character's mouth. It is parented to the D_Jaw bone, so it follows the jaw movement.

2. Enter into the armature's Edit Mode and add a chain of two bones for the tongue, as you can see in the next screenshot. Name them D_TongueBase and TongueTip and make them both children of the D_Jaw bone: (Ctrl + P)|Keep Offset.
   
3. Enter into the armature's Pose Mode Ctrl + Tab. Select the TongueTip bone, hold Shift, select the D_TongueBase bone, press Ctrl + Shift + C, and choose the Stretch To constraint. This will make the base stretch to the position of the TongueTip bone.
4. Select the Otto_Tongue object, hold Shift, select the TongueTip bone, press Ctrl + P, and choose With Automatic Weights. This will bind the tongue mesh to the armature. Adjust the influences of each bone using weight painting.

   Note

   In order to better visualize the tongue object and its bones, you can select the Otto_Body mesh and move it (M) to another layer. You can also hide (H) it (press Alt + H to unhide) or use a Mask Modifier, with the D_Head vertex group and the Invert option selected.

5. Now you can apply a shape to the TongueTip bone and move (M) the D_TongueBase bone to a hidden armature layer. The tongue will be deformed to match the position and rotation of this bone, while inheriting the transformations from the D_Jaw bone.

   The file 004-Tongue-complete.blend has this finished recipe for your reference, in case of any doubts. You can see the resulting deformation in the next screenshot: