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Actor

In MotionBuilder, a humanoid model used to link captured optical or magnetic motion data to a character.

Actor Face

In MotionBuilder, a set of magnetic or optical motion data captured from a performer’s face, which can be mapped to a Character Face asset.

aliasing

A defect or distortion in a television picture caused by interference between two frequencies, for example the luminance and chrominance frequencies. Aliasing appears as moire or herringbone patterns, straight lines that become wavy, or rainbow colors.

See also anti-aliasing

alpha channel

The portion of each pixel's data reserved for transparency information. 32-bit graphics systems contain four channels: three 8-bit channels for red, green, and blue (RGB) and one 8-bit alpha channel.

alpha-blend

An effect in which you assign pixel values that are solid, invisible, or partially transparent. Alpha-blending is often used in games for special effects such as explosions and weapons discharge. When mapped onto polygons, Alpha-blending simulates semi-transparent objects, such as water and glass.

ambient color

The color of an object where it is in shadow. This color is what the object reflects when illuminated by ambient light, i.e. by the (default) global light rather than by direct light.

Ambient color areas in the scene do not appear darker than the (default) global light setting.

animation

The process of creating the illusion of moving images by displaying sequential images in rapid succession. In each successive image, two or more values are changed over time, and the items drawn or recorded in the images appear to move.

anti-aliasing

A technique that corrects aliasing by smoothing the edges of diagonal lines on the screen. Without Anti-aliasing, diagonal lines often have a “jaggy” appearance caused by the stair-step effect of the pixels. Anti-aliasing blurs the edges of the lines.

See also aliasing .

artifact

An undesirable element or defect in motion capture data. These may occur naturally and can be eliminated in order to achieve a better-quality capture.

asset

In MotionBuilder, any element used to create animation, such as models, textures, and shaders.

attribute

See property .

Auxiliary effector

In MotionBuilder, a supplementary effector in a Control rig that corresponds to an existing IK effector. Auxiliary effectors provide additional IK control for a character’s reach, and display as a cube on the corresponding IK effector.

See also effector .

Auxiliary pivot

In MotionBuilder, a sub-control that lets you translate and rotate an IK Control rig effector from a point other than its current location.

See also pivot .