A representation of a four-component vector.
- iOS 8.0+
- macOS 10.8+
- tvOS 9.0+
- watchOS 3.0+
SceneKit uses four-component vectors to represent multiple kinds of data:
Axis-angle rotation or torque. The
zfields contain the normalized x-, y-, and z-components of the rotation axis, and the
wfield contains the rotation angle, in radians, or torque magnitude, in newton-meters.
Color value (or range). The
wfields contain the red, green, blue, and alpha components of the color, or the width of the color variation range in each component.