Facial Tips and Tricks

Estimated reading: 6 minutes

Tuning your facial expressions can be a little tricky since your shapes all perform a specific task and they all play off of each other. We have listed some useful tricks to be aware of as you are creating your facial rig.

Organization

While working on your shapes, it is easy to overlook some of the shapes. It is suggested that you work with a numbered list of blendshape names (located here) given the very large list of blendshapes. This might help make sure nothing is omitted.

Using Deformer-Based Rigs

Use a deformer-based rig (joints and lattices, etc.) to pose out the shapes and then bake out the pose into a model to be used as a blendshape.

This method of working lets you quickly edit a shape if it looks incorrect in the context of animation. Another benefit is that rigs move your points in a predictable manner and will move the same points when you manipulate a control. This helps you avoid pulling some points that clash with another shape.

Range of Movement

Pay attention to ranges of movement. Use the reference model to gauge how far your shape should travel relative to the face.

For example, look at the amount the brow shape moves on the reference model when you pull it up or down. You will want your shape to travel a similar distance proportional to your character. If you go too extreme with the distance your shape travels, it will result in exaggerated movement. This could be a desired result if you are looking for a “toony” type movement, but if you are looking for a more subtle performance, stay in the ranges.

Large Eyed Characters

Large Eyes can be an issue if you are not prepping your model correctly.

A neutral eye on a human is relaxed (not open or closed, just relaxed), though many artists sculpt neutral eyes as fully open. A fully open eye on a large-eyed character gets amplified and could make your character appear as if they are always in a state of shock.

Lip Widen/Narrow Utility Shapes

The lipWiden & lipNarrow are utility shapes. Use them to adjust the mouth width as needed. Avoid making these shapes too wide or narrow, or your character may look off-model and have an unnatural mouth during the performance.

Pay attention to the range for these shapes. Spread the spans of the lips evenly when creating these shapes. Do not bunch up spans in areas, as they may interfere with other shapes such as jawOpen.

Eyelids

Move the eyelids only on these shapes: eyeBlinkL, eyeBlinkR, eyeSquintL, eyeSquintR, eyeL, eyeR, eyeUp, eyeDn. Do not move the lids on other shapes, as they are additive and will cause unwanted eyelid movement.

For example, avoid moving the lid on the eyeCompress shape, which compresses the muscles around the eye. If you do, that movement will add to the eyeBlink shape and your lids will overlap and not close properly.

JawOpen

Human jaws do a combination of rotation and translation downwards. Keep this in mind when creating this shape. If you just rotate, your chin could look as if it’s receding.

Also, JawOpen is an important shape since every open mouth shape leverages it. All lip shapes are used in combination with the jawOpen shape to form open mouth shapes. For that reason, it is good to take a little time while creating this shape and make sure everything is perfect before moving on to lip shapes.

Jaw Left/Right

These are utility shapes mainly used in combination with the jawOpen shape. The two together will rock the jaw back and forth. Keep in mind that they play off of each other. If you get overly “artistic” on the lip shape, it might not play well when combined with the jawOpen shape. It is best to let them just slide across each other from left to right. Just make sure the mouth corners are clean and not crunching. It is also important to make sure that your teeth, gums, and tongue ride along with these shapes.

Eye Rotations

Eye rotations are driven by 4 shapes: eyeUp, eyeDn, eyeLeft, and eyeRight.

These shapes have 0-1 values that the system animates. In Blender, these values can be mapped to other things. For instance, a robot’s face could have an LED screen with graphics that move based on these values, instead of a rotating sphere. This concept can produce some interesting results.

Lip Thickness

The volume of the lips changes depending on the shape. When the lips stretch back (for example, in a smile or “ee” shape), they become thinner and lose volume. When the lips contract or pucker, they gain volume and become thicker. Adding this squash and stretch effect to the lips will make them look more realistic and lively.

lipClose Shapes

These are some of the only “technical” shapes that you will need to create. They are “technical” because they are not intuitive to sculpt. They serve a technical purpose. They are “deltas” that adjust the JawOpen shape to keep the lips closed while the jaw is open.

Here is one way to create these shapes:

Create a temporary jawOpen shape with closed lips (e.g. jawOpenLipsClosed) by copying the jawOpen shape and sculpting it so that the lips are closed.

Make a lipClose shape by combining the jawOpen and temporary jawOpenLipsClosed shapes. Set jawOpen value to -1.0 and jawOpenLipsClosed value to 1.0. This will effectively remove the jawOpen shape from your closedLips shape leaving you with just the delta between the two.

As the last step, the resulting lipClose shape needs to be split into lipCloseLower and lipCloseUpper.
- Duplicate the shape and rename the two shapes to lipCloseLower and lipCloseUpper.
- For lipCloseLower, edit the blendshape by selecting the vertices of the upper lip and masking them out, so that they go back to their neutral position.
- Do the opposite for the lipCloseUpper shape.
- When both lipCloseLower and lipCloseUpper are activated they should add up to the lipClose shape.