Unlike with Inbetweening, Root Motion does not fully adhere to the keyframes set by the user (and can completely ignore them depending on the settings). As a result, the animations it produces are more varied, but can be harder to control.

However, like with Inbetweening, animations produced by Root Motions are not physically accurate. So using this tool in combination with Physics Tools is advised.

To use Root Motion:

1. Create several keyframes representing main phases of the motion.
At minimum, you need two keyframes: at the start and at the end of the motion. Additional keys can be used to enhance the end result.

2. Select the interval on the Timeline.

3. Click the Run Root Motion button on the Toolbar:

This will generate an animation based on the key you’ve set.

Animations produced by Root Motion have the Fixed type of interpolation (i.e. every frame stores a full pose).

Settings

The kind of animation Root Motion produces is controlled by a group of parameters found on the Scene Settings panel, under the Root Motion tab:

Trajectory Force
Defines how much the algorithm should preserve the initial trajectory.
By default, it is set to 0 which means the algorithm would try to preserve as much of the initial trajectory as possible.
Increasing the value makes changes more prominent.
The maximum value of 100 means the algorithm is allowed to make any changes to the trajectory.

(for this parameter, you should use values above 0 only when you have some animation you need to preserve)

Head Direction force
Controls how much the algorithm affects the Direction Controller at the character’s head.
0 means the algorithm is allowed to completely change the controller’s position.
100 means the controller will always be parallel to the ground.

Keyframes force
Defines how much the keyframe poses should be preserved
0 means the algorithm can change poses completely; only things that are preserved are the pelvis coordinates and the orientation of the pelvis Directional Controller.
100 means the algorithm would try to keep the poses fully intact; however, unlike Inbetweening, even at this value there might be changes.

Styles
Sets the style of animation (i.e. the type of motion) the algorithm should produce.
There are several options: Walk, Run, Acrobatic etc.

Style force
Defines how much the Style setting should influence the animation.
Higher values mean stronger influence.

Reference Mode
If this is enabled, Root Motion would use another animation as a reference for its output.
Disabled by default.

The reference animation should be selected beforehand using the Select Root Motion Reference option in the Edit menu:

When a reference is used, the Keyframe Force parameter is not taken into account. The other parameters still work.

Reference force
Defines how much the Reference setting influences the final animation.

Use Fulcrum Motion Cleaning
If this is enabled, the Fulcrum Motion Cleaning tool is applied to the animation produced by Root Motion.

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