Concepts
Functions
The Function interface represents a mathematical function.
Its purpose is to associate a floating value to any input floating value between 0f and 1f.
This function specifies the rate of change of a parameter over time (for example the position of an object).
The library provides a set of functions among the most common ones. Each one contains a convenient instance. For example the singleton for the linear function.
Simple functions
The constant function represents a constant motion whose value is always the stop value.
The linear function represents a uniform linear motion: the velocity is constant (no acceleration or deceleration).
Easing functions
The easing functions come in 3 forms:
Ease-in: the function is eased at the beginning.
Ease-out: the function is eased at the end.
Ease-in-out: the function is eased at the beginning and the end.
Here are the easing functions available in the library:
Circ ease-in
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Circ ease-out
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Circ ease-in-out
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Cubic ease-in
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Cubic ease-out
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Cubic ease-in-out
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Expo ease-in
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Expo ease-out
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Expo ease-in-out
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Quad ease-in
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Quad ease-out
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Quad ease-in-out
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Quart ease-in
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Quart ease-out
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Quart ease-in-out
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Quint ease-in
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Quint ease-out
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Quint ease-in-out
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Sine ease-in
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Sine ease-out
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Sine ease-in-out
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Back ease-in
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Back ease-out
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Back ease-in-out
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Bounce ease-in
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Bounce ease-out
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Bounce ease-in-out
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Elastic ease-in
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Elastic ease-out
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Elastic ease-in-out
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Custom Function
It is possible to create custom functions by creating a class implementing the Function interface.
The computeValue(float) method should return a value between 0f and 1f.
Motion
The Motion class is used to describe the movement of an element. It is made of a function, a start value, a stop value and a duration.
It proposes a convenient method Motion.getValue(long) to retrieve the position of the element at the specified elapsed time.