Five Prayer Time

this application show current time & five prayer time for muslim specific for my current city (Bandung, latitude:6.54 & longitude: 107.36), with polar clock as visualization.

to compute prayer time, i use algorithm that described in this site http://tanzil.info/praytime/doc/calculation/.

source code:

import javafx.scene.shape.*;
import javafx.animation.*;
import java.util.*;
import javafx.scene.shape.*;
import javafx.scene.paint.Color;
import javafx.util.Math;

import javafx.scene.CustomNode;

import javafx.scene.Group;
import javafx.scene.Scene;
import javafx.stage.Stage;

import javafx.date.DateTime;
import javafx.scene.control.Label;
import javafx.scene.image.ImageView;
import javafx.scene.image.Image;

import java.text.SimpleDateFormat;
/**
 * @author Muhammad Hakim A
 */

var hours;
var minutes;
var seconds;
var date;
var day;
var month;
var year;
var cal;
var time = Timeline {
    repeatCount: Timeline.INDEFINITE
    keyFrames: [
        KeyFrame {
            time: 100ms
            action:function(){
                    cal = createCalendar();
                    seconds = (cal.get(Calendar.SECOND) + (cal.get(Calendar.MILLISECOND) as Float)/1000)/60;
                    minutes = (cal.get(Calendar.MINUTE) + seconds)/60;
                    hours = (cal.get(Calendar.HOUR) + minutes)/12;
                   }
        }
    ]
}

var sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
var today:String = "{sdf.format(Calendar.getInstance().getTime())}";
function createCalendar() {
    var date = new Date();
    def calendar = Calendar.getInstance();
    calendar.setTime(new Date());

    calendar
}

// class polarclock
class PolarClock extends CustomNode{
        public var cX=10;
        public var cY=10;
        public var strokeWidth = 5;
        public var radius=50;
        public var secLength= 180;
        public var minLength= 90;
        public var hourLength= 30;
        public var text = "";

        override function create(){
            return Group{
                    opacity: 0.85
                    content:[
                            Arc {// second
                                centerX: cX, centerY: cY
                                radiusX: radius, radiusY: radius
                                startAngle: 90, length:bind -secLength+strokeWidth*360.0/(4*Math.PI*radius)
                                stroke: Color.GREEN
                                fill: null
                                strokeWidth: strokeWidth
                            }
                            Arc {// minute
                                centerX: cX, centerY: cY
                                radiusX: radius-17, radiusY: radius -17
                                startAngle: 90, length:bind -minLength+strokeWidth*360.0/(4*Math.PI*radius)
                                stroke: Color.RED
                                fill: null
                                strokeWidth: strokeWidth
                            }
                            Arc {// hour
                                centerX: cX, centerY: cY
                                radiusX: radius-34, radiusY: radius-34
                                startAngle: 90, length:bind -hourLength+strokeWidth*360.0/(4*Math.PI*radius)
                                stroke: Color.BLUE
                                fill: null
                                strokeWidth: strokeWidth
                            }
                            Label {
                                    translateY : cY+radius + 10
                                    translateX : cX - radius/2;
                                    text: text
                                    textFill: Color.GOLD
                            }
                    ];
            };
        }
}

// prayer time calculator
def JD1970 = 2440587.5;
def d2r = Math.PI/180;
def r2d = 57.2957795;
var dt:DateTime = DateTime{};
var jd = JD1970 + Math.floor((dt.instant + 0.5)/(1000 * 60 * 60* 24));
var D = jd - 2451545.0;  // jd is the given Julian date

var g = 357.529 + 0.98560028* D;
var q = 280.459 + 0.98564736* D;
var L = q + 1.915* sin(g) + 0.020*sin(2*g);

var R = 1.00014 - 0.01671*cos(g) - (1.4e-4)*cos(2*g);
var e = 23.439 - (3.6e-7)* D;
var RA = atan2(cos(e)*sin(L),cos(L))/15;

var d = asin(sin(e)*sin(L));  // declination of the Sun
var EqT = q/15 - RA;  // equation of time

// Bandung info
def TZ = 7;
def lat = 6.54;
def lng = 107.36;

var dzuhr = fixhour(12 + TZ - lng/15 - EqT);
var fajr = dzuhr - T(18);
var fajrh = [to12h(Math.floor(fajr)),to60((fajr - Math.floor(fajr))*60)];
var isya = dzuhr + T(17);
var ashr = dzuhr + 1.0/15*acos((sin(acotan(1.0+tan(lat-d)))
                    -(sin(lat)*sin(d)))/(cos(lat)*cos(d)));
var maghrib = dzuhr + T(0.8333);

function T(a:Double) {
return (1.0/15)*acos(-sin(a)-sin(lat)*sin(d)/cos(lat)*cos(d)) }
function fixhour(a:Float)
{
    var b = a - 24.0 * (Math.floor(a / 24.0));
    if (b < 0) b= b + 24.0;
    return b;
}

function to12h (h:Integer) { if (h>12) h-12 else h }
function to60(m:Integer) { if(m>60) m-60 else m }
function sin (a:Double) { Math.sin(a*d2r)}
function cos (a:Double) { Math.cos(a*d2r)}
function tan (a:Double) { Math.tan(a*d2r)}
function acotan (a:Double){ Math.atan(1.0/a)*r2d }
function acos(a:Double) { Math.acos(a)*r2d}
function asin(a:Double) { Math.asin(a)*r2d}
function atan(a:Double) { Math.atan(a)*r2d}
function atan2 (y:Double,x:Double) { Math.atan2(y, x)*r2d }

public function run () {
    time.play();
    println("{today}");
    var scene:Scene = Scene {
        width: 500
        height: 500
        fill: Color.BLACK
        content: [
               ImageView {
                        image: Image {
                                url: "{__DIR__}Masjid.png"
                        }
                }

               PolarClock{
                    radius:120
                    cX: 150
                    cY: 160
                    strokeWidth:15
                    secLength:bind 360*seconds
                    minLength: bind 360*minutes
                    hourLength:bind 360*hours
                    text: bind "today: {today}"
                  }
                  //fajr
                 PolarClock{
                    radius:50
                    cX: 340
                    cY: 60
                    strokeWidth:11
                    secLength: 360
                    minLength: fajrh[1]*6
                    hourLength: fajrh[0]*30
                    text: "Fajr: {fajrh[0]}:{fajrh[1]} am"
                  }
                  //dzuhr
                 PolarClock{
                    radius:50
                    cX: 340
                    cY: 200
                    strokeWidth:11
                    secLength: 360
                    minLength: to60((dzuhr - Math.floor(dzuhr))*60)*6
                    hourLength: to12h(Math.floor(dzuhr))*30
                    text: "Dzuhr"
                  }
                  //ashr
                 PolarClock{
                    radius:70
                    cX: 340
                    cY: 360
                    strokeWidth:11
                    secLength: 300
                    minLength: to60((ashr - Math.floor(ashr))*60)*6
                    hourLength: to12h(Math.floor(ashr))*30
                    text: "Ashr"
                  }
                  //maghrb
                 PolarClock{
                    radius:50
                    cX: 190
                    cY: 400
                    strokeWidth:11
                    secLength: 350
                    minLength: to60((maghrib - Math.floor(maghrib))*60)*6
                    hourLength: to12h(Math.floor(maghrib))*30
                    text: "Maghrib"
                  }
                  //isya
                 PolarClock{
                    radius:50
                    cX: 70
                    cY: 400
                    strokeWidth:11
                    secLength: 360
                    minLength: to60((isya - Math.floor(isya))*60)*6
                    hourLength: to12h(Math.floor(isya))*30
                    text: "Isya"
                  }]
        }

    def stage:Stage = Stage {
        title: "Five Prayer Time"
        scene: scene
    }
    stage.visible = true;
}