Morph Facial Animation
Morphing is the simplest facial method and good for new and advanced artists. Morphing takes vertex positions from duplicated models and blends them onto the selected morph model. By blending from multiple 'reference' models you can generate a number of expressions for the character while retaining flexibility on editing the original model. Morphs can be very effective to generate special facial affects like 'lump on head' for cartoon scenes as the head mesh can be happily manipulated with little issues. One interesting affect of morphs is that you can invert the morph % this can turn a blink into a stare or a smile into a sulk, as the morph inverts the vertex position. Some of these inverts will require limits so no distortions appear.
- Very flexible to manipulate the vertex's
- Can add up to 100 different morphs
- Can manipulate UV mapping (for control model only)
- Cannot add or remove vertex's to morph targets & control model (if you do this the vertex order for the morph targets will go out of place, or cannot be loaded into the morpher modifier)
- Takes up more memory than skinning
1. A control model is duplicated a number of times using reference copies. These reference copies will act as the 'morph targets'.
The control model acts as the original model and should be modified if you want to modify all the morph models at the same time i.e. change shape of face, nose, eyes etc. This makes global modifications easy
2. On each of the reference copies an edit poly stack is added and the mesh is deformed into the right morph expression.
If you're not happy with the shape of the morph add a new edit poly stack and delete the previous added stack. This will revert the morph into its original form.
Turning on & off the stack will help you see the changes you have made to the morph
A total of 11 morph targets will need to be created for the primary expressions. Note that the teeth have been included in the morph mesh.
Left / right eye close
For blinks and wide-awake expressions
Left / right smile
For smiles and sulk expressions
For Jaw movements
For unsure facial expressions
Bottom lip drop
For Speech, grins
Top lip up
For sneering and speech
For kiss expressions, speech and wide mouth.
3. Once you have created the morphs you can generate a reference clone of the control model to generate a morpher model. This will be used to blend the facial expressions and used for rendering.
Add a morpher modifier to the morpher 'render' head and if needed add a skin modifier placed above it to match it to the characters body position.
Tip: If you want to copy the body's skin modifier to the head simply select the skin stack on the body and drag it onto the head.
If you want to copy the skin stack over to the head as an instance simply hold 'CTL' and drag it onto the head. The instance stack will appear in an italic slanted font.
This process works best when using envelopes for bones.
To finish off a set of eyes are added to the head and a LookAt constraint is added to their rotations to target a helper point.
Simply move the helper point to make the characters eyes look at the point of focus.
4. Once you have added the morpher modifier you can load in the morph targets with the 'load multiple targets' button in the morph modifier menu. Then simply select the morph targets you wish to use.
With each of the morph targets loaded, you will need to set the morph limits in 'channel limits'. This option is greyed out when 'global limits' are applied in the 'global parameters' in the 'morph modifier'.
Tip: if you modify a morph target you will need to have this updated in the morph modifier. Click on the update button to have the latest targets reloaded.
Tip: Morphing can also be used to generate random faces. This can be used for crowds where you may wish to reuse the same mesh & morph sets while mixing it with new morphs and texture replacements to generate new people.