Interpolate

Overview

The Interpolate Node is used primarily for animating the Attributes of Objects.

The Node calculates the intermediate Values between a start (From) and end (To) Value. These transitional Values are calculated a number of times per second, defined in the Frame Rate (fps) Attribute, over a certain length of time, defined in the duration Duration (s) Attribute.

Every time a new Value is calculated, the Output Pulse is also triggered.

Attributes

Input

Attribute	Type	Description
Data Type	Drop-down	The numerical Type of Data that will interpolated.
Duration (s)	Float	The length of time that the Value will be interpolated over, in seconds.
From	Defined in the Data Type Attribute.	The initial Value.
To	Defined in the Data Type Attribute.	The end Value.

Interpolation

Attribute	Type	Description
Type	Drop-down	The easing method, used to calculate the intermediate Values (see below).
Mode	Drop-down	The playback setting for repeated animations (see below).
Count	Int	The amount of times the interpolation will run (not available in Once mode or when Infinite is enabled).
Infinite	Bool	If enabled, the animation repeats, or alternates indefinitely.
Frame Rate (fps)	Float	The amount of times per second that the Value is calculated.

More about the Mode Attribute

Once

Once means that the animation will play only once and then stop any further evaluation:

Repeat

Repeat allows us to repeat the animation a set number of times, defined in the Count Attribute. Note that this will only work if Infinite is set to false. If Infinite is turned on, the animation will repeat indefinitely.

Alternate

Lastly, we have the Alternate option. This causes the interpolation to animate forwards and then backwards. As with the Repeat option, this will repeat forever if Infinite is enabled, or until it has played the amount of times defined in Count.

Note that backwards animations also count as an animation in themselves, so odd Count Values will cause the animation to stop at the To position, while an even Value will terminate the animation at the initial From position.

Also note that alternating animations will also reverse the easing function. If it eases in from the start to end position, then it will ease out from the end, back to the start position.

More about the Type Attribute

INCARI offers many different interpolation types, which determine the way that the transition between To and From is calculated, and the easing of the animation.

Non-easing Interpolation Types

• Linear - interpolates between the Values linearly at a constant pace.

• Constant - like Linear except that the Value is rounded down to the nearest whole number.

Easing Interpolation Types

Although linear interpolation does have its uses, a more stylised effect is often required to make an animation more interesting. This is often achieved using an acceleration and/or deceleration of the animation speed over time. In animation, this is often referred to as easing.

The easing functions in INCARI are named, based on a naming convention, which offers some insight into how the interpolation is calculated.

First we have the prefixes, which represent different "levels" of easing. Some are very strong, while others are more subtle. The prefixes are Circ, Cube, Exp, Quad and Sin.

Then we have the suffixes, which show whether the animation eases in (EaseIn), eases out (EaseOut), or both (EaseInOut).

Ease In

ExpEaseIn:

Ease Out

ExpEaseOut:

Ease In Out

ExpEaseInOut:

Inputs

Input	Type	Description
Duration (s)	Float	The length of time that the Value will be interpolated over, in seconds.
Count	Int	The amount of times the interpolation will run (not available in Once mode or when Infinite is enabled).
From	Defined in the Data Type Attribute.	The initial Value.
To	Defined in the Data Type Attribute.	The end Value.
Start	Pulse	Initiates the interpolation.
Reset	Pulse	Reverts the Value to the initial From Value and cancels any further Pulse Outputs.

Outputs

Output	Type	Description
Pulse Output (►)	Pulse	Fires every time Value is evaluated (defined in the Frame Rate (fps) Attribute.
Value	Defined in the Data Type Attribute.	The current intermediate Value between From and To.
OnReset	Pulse	Fired once the interpolation has been reset by a Pulse plugged into the Reset Input Socket.
OnEnd	Pulse	Triggers once all of the interpolations are complete (never triggers is Infinite is enabled).

External Links

Easing Function Cheat Sheet on Easings.net.