Add Motion with JavaFX Animation - JavaFX: Developing Rich Internet Applications - page 198

Bessel

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Figure 7.7 Bessel Function

Listing 7.4 Bessel Interpolator

package animation;

import javafx.animation.Interpolator ;
import javafx.animation.Interpolatable ;
import java.lang.Math;

public class Bessel extends Interpolator {
// Bessel integer order
public-init var order:Integer = 0;
// Amplitude of resulting wave
public-init var amplitude = 40.0;
// frequency of resulting wave
public-init var frequency = 600;

public override function interpolate(startValue:Object,
endValue:Object, fraction:Number):Object {
if(fraction == 1.0) {
return endValue;
}
if(startValue instanceof java.lang.Number and
endValue instanceof java.lang.Number) {
var start : Number = startValue as Number;
var end: Number = startValue as Number;
var val = start + j(frequency * fraction) *
amplitude ;
if(startValue instanceof java.lang.Integer and
endValue instanceof java.lang.Integer) {
(val + 0.5).intValue();
}else {