Tweening comes from the english word in between, and has been shortened from in-betweening. It provides various methods in the form of functors that calculate values in between 0 and 1 according to various functions. Tweening can be used for purposes in the vicinity of interpolation, such as the calculation of gradients in images and or palettes. It provides linear and non-linear functions.

The following chapters do not show all functions. The square and square root variants are mere examples of a more general class of tweening functions, where the power can be chosen arbitrarily. The tweening sample visualizes some more tweening functions.

Exact definitions of the formulas can be found in the function reference documentation.