Ogre Skeletal Animations

Facial animation and full-body animations work together to create a realistic character.  Previewing body animations while editing facial animations is possible in FaceFX.  Body animations can also be triggered by FaceFX events, allowing artists to create a speech-synchronized body gesture systems using short full-body animation clips.  Full body animations can be brought into FaceFX using the FBX pipeline.

Bone Weights

FaceFX animations can conflict with skeleton animations if they are influencing the same bone.  Any bones not contained in the FaceFX Rest Pose (see below) will be completely controlled by the skeletal animations.  Bones in the rest pose are by default controlled by FaceFX unless bone weights are set differently.  Default bone weights are set from the Actor menu, and these can be over-ridden on a per-animation basis using FxBoneWeightNodes.

Rest Pose - The rest pose defines all of the bones that FaceFX drives with bone poses.  Using the FBX pipeline, a bone is added to the rest pose if it moves in one of the created bone poses (the bone poses are compared to frame 0 and any bones that move are added to the rest pose and the bone pose).  In the FaceFX Exporters, the rest pose is explicitly created by exporting it and selecting the bones.

Preview Animation

• Controlled via the previewanim command.
• Selected from and visible in the timeline
• Can loop (as opposed to Event Preview Animations, which can not)

Event Animations

• Animations are triggered by an event’s payload. For example: _game: playanim _
• The start time, magnitude scale, duration scale, blendin, and blendout parameters of the parent event are used to modify how the preview animation is played.
• Multiple full-body animations can be played simultaneously if they are different animations. 

Integrating with an External Engine

The game or application using the FaceFX SDK is responsible for blending the output FaceFX bone transforms with other skeletal or physics systems.  The bone weight values are provided for informational purposes only, and do not impact the bone transforms output by the FaceFX SDK.

Limitations

FaceFX Studio does not have a fully featured skeletal animation system.  Only the basics required to play full-body animations has been implemented.  Below are some restrictions:

• Due to a restriction in ogre, only one copy of a single animation can be played at once.  If an animation is playing when another request is received to play it again, the second request will be ignored and an error will be printed to the log. 
• Animations must control the entire skeleton. Other than using Bone Weights, there is no way to get an animation to play on only part of the skeleton.
• Animations can not influence the skeleton after they have finished playing.
• Animations can not be grouped into layers for prioritizing weighting.