public abstract class Interpolator extends java.lang.Object
interpolate
methods, which are
used to calculate interpolated values. Various builtin 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()
".
Modifier and Type  Field and Description 

static Interpolator 
DISCRETE
Builtin interpolator that provides discrete time interpolation.

static Interpolator 
EASE_BOTH
Builtin interpolator instance that provides ease in/out behavior.

static Interpolator 
EASE_IN
Builtin interpolator instance that provides ease in behavior.

static Interpolator 
EASE_OUT
Builtin interpolator instance that provides ease out behavior.

static Interpolator 
LINEAR
Builtin interpolator that provides linear time interpolation.

Modifier  Constructor and Description 

protected 
Interpolator()
The constructor of
Interpolator . 
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. 
java.lang.Object 
interpolate(java.lang.Object startValue,
java.lang.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 intangent and outtangent are
identical.

static Interpolator 
TANGENT(Duration t1,
double v1,
Duration t2,
double v2)
Create a tangent interpolator.

public static final Interpolator DISCRETE
interpolate()
is endValue
only when the
input fraction
is 1.0, and startValue
otherwise.public static final Interpolator LINEAR
interpolate()
is startValue
+ (endValue
 startValue
) * fraction
.public static final Interpolator EASE_BOTH
An easeboth 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.
public static final Interpolator EASE_IN
An easein 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.
public static final Interpolator EASE_OUT
An easeout 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.
protected Interpolator()
Interpolator
.public static Interpolator SPLINE(double x1, double y1, double x2, double y2)
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
).x1
 x coordinate of the first control pointy1
 y coordinate of the first control pointx2
 x coordinate of the second control pointy2
 y coordinate of the second control pointpublic static Interpolator TANGENT(Duration t1, double v1, Duration t2, double v2)
Timeline
.
If used in a KeyFrame
after a KeyFrame that has different interpolator,
it's treated as if the outtangent 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.
t1
 The delta time of the intangent, relative to the KeyFramev1
 The value of the intangentt2
 The delta time of the outtangent, relative to the KeyFramev2
 The value of the outtangentpublic static Interpolator TANGENT(Duration t, double v)
Timeline
, because for these key frames only one tangent is
used.t
 The delta time of the tangentv
 The value of the tangentTANGENT(Duration, double, Duration, double)
public java.lang.Object interpolate(java.lang.Object startValue, java.lang.Object endValue, double fraction)
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()
.
startValue
 start valueendValue
 end valuefraction
 a value between 0.0 and 1.0public boolean interpolate(boolean startValue, boolean endValue, double fraction)
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()
.
startValue
 the first data pointendValue
 the second data pointfraction
 the fraction in [0.0...1.0]
public double interpolate(double startValue, double endValue, double fraction)
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()
.
startValue
 the first data pointendValue
 the second data pointfraction
 the fraction in [0.0...1.0]
public int interpolate(int startValue, int endValue, double fraction)
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()
.
startValue
 the first data pointendValue
 the second data pointfraction
 the fraction in [0.0...1.0]
public long interpolate(long startValue, long endValue, double fraction)
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()
.
startValue
 the first data pointendValue
 the second data pointfraction
 the fraction in [0.0...1.0]
protected abstract double curve(double t)
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.Copyright (c) 2008, 2013, Oracle and/or its affiliates. All rights reserved. Use is subject to