R

reference node: A null or joint that acts as the root of an entire model and is the parent of the models’ Hips.
reflectivity: Reflection effects created by the light that bounces off an object or model.
Relations: See relational constraint .
relational constraint: Also referred to as Relations, constraints that perform custom operations on the data of a source object to determine the behavior of the constrained object.

See also constraint .
remote port: An additional port provided by a serial device where you can physically connect input and output devices.
render: To generate an image file, a sequence of image files, or movie file(s) using the mathematical descriptions of the objects that compose the scene.
rest pose: The default position at which a Character Face asset is at rest.
retargeting: The process of taking the animation data mapped to one character, applying that animation to another character to drive its animation without having the need to plot (or bake) the animation.
Rigid body: Two or more markers grouped to correct occlusion.
roll: A rotation around the X-axis. For example, the rolling of a log.
rotation: The process of changing all the points on an object to reflect the degree of rotation around each of the three axes.