javafx.animation

Class Interpolator

java.lang.Object

javafx.animation.Interpolator

public abstract class Interpolator
extends Object

The abstract class defines several interpolate methods, which are used to calculate interpolated values. Various built-in implementations of this class are offered. Applications may choose to implement their own Interpolator to get custom interpolation behavior.

A custom Interpolator has to be defined in terms of a " curve()".

Since:

JavaFX 2.0

Field Summary

Fields
Modifier and Type	Field and Description
`static Interpolator`	`DISCRETE` Built-in interpolator that provides discrete time interpolation.
`static Interpolator`	`EASE_BOTH` Built-in interpolator instance that provides ease in/out behavior.
`static Interpolator`	`EASE_IN` Built-in interpolator instance that provides ease in behavior.
`static Interpolator`	`EASE_OUT` Built-in interpolator instance that provides ease out behavior.
`static Interpolator`	`LINEAR` Built-in interpolator that provides linear time interpolation.

Constructor Summary

Constructors
Modifier Constructor and Description

protected Interpolator()
The constructor of Interpolator.

Constructors
Modifier	Constructor and Description
`protected`	`Interpolator()` The constructor of `Interpolator`.

Method Summary

All MethodsStatic MethodsInstance MethodsAbstract MethodsConcrete Methods
Modifier and Type	Method and Description
`protected abstract double`	`curve(double t)` Mapping from [0.0..1.0] to itself.
`boolean`	`interpolate(boolean startValue, boolean endValue, double fraction)` This method takes two `boolean` values along with a `fraction` between `0.0` and `1.0` and returns the interpolated value.
`double`	`interpolate(double startValue, double endValue, double fraction)` This method takes two `double` values along with a `fraction` between `0.0` and `1.0` and returns the interpolated value.
`int`	`interpolate(int startValue, int endValue, double fraction)` This method takes two `int` values along with a `fraction` between `0.0` and `1.0` and returns the interpolated value.
`long`	`interpolate(long startValue, long endValue, double fraction)` This method takes two `int` values along with a `fraction` between `0.0` and `1.0` and returns the interpolated value.
`Object`	`interpolate(Object startValue, Object endValue, double fraction)` This method takes two `Objects` along with a `fraction` between `0.0` and `1.0` and returns the interpolated value.
`static Interpolator`	`SPLINE(double x1, double y1, double x2, double y2)` Creates an `Interpolator`, which `curve()` is shaped using the spline control points defined by (`x1`, `y1` ) and (`x2`, `y2`).
`static Interpolator`	`TANGENT(Duration t, double v)` Creates a tangent interpolator, for which in-tangent and out-tangent are identical.
`static Interpolator`	`TANGENT(Duration t1, double v1, Duration t2, double v2)` Create a tangent interpolator.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail
- DISCRETE
```
public static final Interpolator DISCRETE
```
  Built-in interpolator that provides discrete time interpolation. The return value of interpolate() is endValue only when the input fraction is 1.0, and startValue otherwise.
- LINEAR
```
public static final Interpolator LINEAR
```
  Built-in interpolator that provides linear time interpolation. The return value of interpolate() is startValue + (endValue - startValue) * fraction.
- EASE_BOTH
```
public static final Interpolator EASE_BOTH
```
  Built-in interpolator instance that provides ease in/out behavior.
  An ease-both interpolator will make an animation start slow, then accelerate and slow down again towards the end, all in a smooth manner.
  
  The implementation uses the algorithm for easing defined in SMIL 3.0 with an acceleration and deceleration factor of 0.2, respectively.
- EASE_IN
```
public static final Interpolator EASE_IN
```
  Built-in interpolator instance that provides ease in behavior.
  An ease-in interpolator will make an animation start slow and then accelerate smoothly.
  
  The implementation uses the algorithm for easing defined in SMIL 3.0 with an acceleration factor of 0.2.
- EASE_OUT
```
public static final Interpolator EASE_OUT
```
  Built-in interpolator instance that provides ease out behavior.
  An ease-out interpolator will make an animation slow down toward the end smoothly.
  
  The implementation uses the algorithm for easing defined in SMIL 3.0 with an deceleration factor of 0.2.

Constructor Detail
- Interpolator
```
protected Interpolator()
```
  The constructor of Interpolator.

Method Detail
- SPLINE
```
public static Interpolator SPLINE(double x1,
                                  double y1,
                                  double x2,
                                  double y2)
```
  Creates an Interpolator, which curve() is shaped using the spline control points defined by (x1, y1 ) and (x2, y2). The anchor points of the spline are implicitly defined as (0.0, 0.0) and (1.0, 1.0).
  
  Parameters:
  
  x1 - x coordinate of the first control point
  
  Returns:
  
  A spline interpolator
- TANGENT
```
public static Interpolator TANGENT(Duration t1,
                                   double v1,
                                   Duration t2,
                                   double v2)
```
  Create a tangent interpolator. A tangent interpolator allows to define the behavior of an animation curve very precisely by defining the tangents close to a key frame. A tangent interpolator defines the behavior to the left and to the right of a key frame, therefore it is only useful within a Timeline. If used in a KeyFrame after a KeyFrame that has different interpolator, it's treated as if the out-tangent of that KeyFrame was equal to the value in the KeyFrame.
  
  The parameters define the tangent of the animation curve for the in tangent (before a key frame) and out tangent (after a key frame). Each tangent is specified with a pair, the distance to the key frame and the value of the tangent at this moment.
  
  The interpolation then follows a bezier curve, with 2 control points defined by the specified tangent and positioned at 1/3 of the duration before the second KeyFrame or after the first KeyFrame. See the picture above.
  
  Parameters:
  
  t1 - The delta time of the in-tangent, relative to the KeyFrame
  
  Returns:
  
  the new tangent interpolator
- TANGENT
```
public static Interpolator TANGENT(Duration t,
                                   double v)
```
  Creates a tangent interpolator, for which in-tangent and out-tangent are identical. This is especially useful for the first and the last key frame of a Timeline, because for these key frames only one tangent is used.
  
  Parameters:
  
  t - The delta time of the tangent
  
  Returns:
  
  the new Tangent interpolator
  
  See Also:
  
  TANGENT(Duration, double, Duration, double)
- interpolate
```
public Object interpolate(Object startValue,
                          Object endValue,
                          double fraction)
```
  This method takes two Objects along with a fraction between 0.0 and 1.0 and returns the interpolated value.
  If both Objects implement Number, their values are interpolated. If startValue implements Interpolatable the calculation defined in interpolate() is used. If neither of these conditions are met, a discrete interpolation is used, i.e. endValue is returned if and only if fraction is 1.0, otherwise startValue is returned.
  
  Before calculating the interpolated value, the fraction is altered according to the function defined in curve().
  
  Parameters:
  
  startValue - start value
  
  Returns:
  
  interpolated value
- interpolate
```
public boolean interpolate(boolean startValue,
                           boolean endValue,
                           double fraction)
```
  This method takes two boolean values along with a fraction between 0.0 and 1.0 and returns the interpolated value.
  Before calculating the interpolated value, the fraction is altered according to the function defined in curve().
  
  Parameters:
  
  startValue - the first data point
- interpolate
```
public double interpolate(double startValue,
                          double endValue,
                          double fraction)
```
  This method takes two double values along with a fraction between 0.0 and 1.0 and returns the interpolated value.
  Before calculating the interpolated value, the fraction is altered according to the function defined in curve().
  
  Parameters:
  
  startValue - the first data point
- interpolate
```
public int interpolate(int startValue,
                       int endValue,
                       double fraction)
```
  This method takes two int values along with a fraction between 0.0 and 1.0 and returns the interpolated value.
  Before calculating the interpolated value, the fraction is altered according to the function defined in curve().
  
  Parameters:
  
  startValue - the first data point
- interpolate
```
public long interpolate(long startValue,
                        long endValue,
                        double fraction)
```
  This method takes two int values along with a fraction between 0.0 and 1.0 and returns the interpolated value.
  Before calculating the interpolated value, the fraction is altered according to the function defined in curve().
  
  Parameters:
  
  startValue - the first data point
- curve
```
protected abstract double curve(double t)
```
  Mapping from [0.0..1.0] to itself.
  
  Parameters:
  
  t - time, but normalized to the range [0.0..1.0], where 0.0 is the start of the current interval, while 1.0 is the end of the current interval. Usually a function that increases monotonically.

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Documentation extracted from JavaFX API Documentation.
Licensed under the GNU General Public License, version 2, with the Classpath Exception.
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Class Interpolator

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

DISCRETE

LINEAR

EASE_BOTH

EASE_IN

EASE_OUT

Constructor Detail

Interpolator

Method Detail

SPLINE

TANGENT

TANGENT

interpolate

interpolate

interpolate

interpolate

interpolate

curve