Select the Biped > Motion panel > Layers rollout
Controls in the Layers rollout allow you to add layers of animation above the original biped animation. This is a powerful way of making global changes to your character animation. For example, simply add a layer and rotate the spine forward at any frame, and a run cycle becomes a crouched run. The original biped motion is kept intact and can be viewed by switching back to the original layer. Layers can be viewed individually or as a composite of all the animation in all the layers. Layers behave like a freeform animation; the biped can adopt any position.
Tip: You can globally translate both a footstep and freeform animation by doing a layered edit on the Center of Mass. For example, by adding a layer and moving the Center of Mass you can move a freeform or footstep animaiton.
Layers will allow you to easily adjust raw motion capture data, which contains keys at every frame. Simply add a layer and keyframe the biped. The original layer is displayed as red bones.
Tip: To compare subtle motion between layers, turn off Object and turn on Bones on the Display rollout. You can compare the layer to the original with the red bone display.
Layers can be named for clarity.
Use Layers for global changes or for longer periods of interpolation. Use Set Multiple Keys for changing a group of selected keys in Track View. Set Multiple Keys is accessed from the Keyframing rollout.
With Layers, you can interpolate the position of the biped over a wide range of frames. To change the biped posture over a period of one hundred frames during a run cycle, simply create a new layer and create two spine keys one hundred frames apart; during the run the posture changes during that period.
Set Multiple Keys is useful to correct for periodic keys. If a character bobs his head from left to right and all the "head right" keys need to be exaggerated, then open Track View, select all the "head right" keys, rotate the biped head and click Apply Increment in the Set Multiple Keys dialog.
To make a global posture change to the biped
Select a biped, then click Create Layer.
Turn on the Animate button, then rotate a spine object on the biped forward.
The biped leans forward through the animation.
Use Set Snap Key at a frame where the character's posture should return to its original motion.
Next-Previous Layer: Navigate through the layers using the up and down arrows.
Level: This field displays the current layer (Level).
Active: Toggles the displayed layer on and off.
Name Field: Type a name to easily identify a layer.
Create Layer: Creates a layer, and the Level field increments.
Position the biped to create keys in a layer.
Delete Layer: Deletes the current layer.
All layer numbers 'above' the one deleted are decremented by one.
Collapse Layers: Collapses all the layers into layer 0.
Legs that stray from the original footsteps in higher layers are "pulled in" to the original footsteps.
Snap Set Key: Snaps the Selected biped part to its original position in layer 0 and creates a key.
Use this in higher layers to return the selected biped part to the original motion. If a layer has a posture key that bends the character forward at frame 2 and you want to return the biped to its original posture motion at frame 50, use Snap Set Key at frame 50 with a spine object selected. The character will interpolate from its forward posture position to its original posture position between frame 2 and 50.
Activate Only Me: View the animation in the selected layer.
Select Play after turning on Activate Only Me to view a layer's keys in motion.
Activate All: Activates all the layers.
Playing the animation shows a composite of all the layers.
Visible Before: Sets the number of preceeding layers to display as stick figures.
Visible After: Sets the number of succeeding layers to display as stick figures.
Key Highlight: Displays keys by highlighting the stick figures.