Week 11 - Animation Flashcards
What is traditional cel-based animation?
All frames are drawings composed by multiple transparent layers (cel) and differ (slightly) from one frame to the next to create the illusion of motion
What is stop-motion animation?
In stop motion the animation is created by moving characters and objects by small increments to create the illusion of movement
What are Animation Variables known as?
Avars
What is physics-based animation?
Assign physical properties to objects (mass, forces etc) and calculate motion from simulating physics (dynamics, collision)
What are particle systems and flocking behaviour?
Allows modelling of complex motions as the simulation of a large number of simple particles
Particles are spawned, transformed and killed at each update according to physics rules
Flocking behaviours also implements particle awareness of neighbours in their dynamics
What is the concept of key frames?
Motion is defined by specifying the scene only at specific instants, in-between frames are generated by interpolation
What is the concept of morphing?
Morphing stores a deformed version of the mesh, and uses interpolation to calculate intermediate meshes
What is morphing useful for?
Animating deformable surfaces that are not clearly tied to a skeleton
What is rigging?
To control a mesh animation, a hierarchical skeletal structure (or rig) is created, with articulated joints and mesh vertices are attached to it. Each bone in the skeleton is connected to a parent bone
What is the concept of forward kinematics?
Forward kinematics calculate the pose of a joint from its parents
What is the concept of inverse kinematics?
Inverse kinematics calculate the skeleton parameters to bring a given joint to a specified pose
What is skinning?
The process of defining how a model’s surface deforms according to changes in the skeletal poe
What is the concept of the Uncanny Valley?
The (unproven) hypothesis that characters that look almost, but not quite, human cause feelings of revulsion
What is the concept of motion capture?
The process of recording the movement of human actors for animating a computer model
What is motion capture also known as?
Mocap
How does motion capture work?
Multiple synchronised cameras viewing the subject from different angles
Reflective markers are placed at joint locations on the subject
A marker’s position is estimated by triangulating from all camera views
Finally, the skeleton is animated according to recorded motion
How does markerless motion capture work?
The subject is recorded simultaneously from all angles, and the background is subtracted. The shape is then reconstructed in all 8 views and texture is collected from the images
What do motion graphs represent?
Possible transactions between recorded motions
