scSunriseSet – Usage¶

calculateSunRiseSet¶

Calculates the sunrise and sunset times for the specified coordinates and returns the result directly. The calculation is based on the current date from the system clock.

Parameters

Parameter	Type	Description
`lat`	`Number`	Latitude in decimal degrees (e.g. `59.33` for Stockholm)
`lon`	`Number`	Longitude in decimal degrees (e.g. `18.07` for Stockholm)

Return value: Object with the properties:

Property	Type	Example	Description
`rise`	`String`	`"06:15"`	Sunrise time in `HH:MM` format (local time)
`set`	`String`	`"20:43"`	Sunset time in `HH:MM` format (local time)

var sun = scSunriseSet.calculateSunRiseSet(59.33, 18.07);
Debug.Print("Sunrise: " + sun.rise);
Debug.Print("Sunset: " + sun.set);

SunRiseSetCheck¶

Creates an event-driven monitoring object that calculates sunrise and sunset times once per day. The event is sent immediately at startup and then every day shortly after midnight.

Parameters

Parameter	Type	Default value	Description
`latitude`	`Number`	`55.6405`	Latitude in decimal degrees
`longitude`	`Number`	`13.2134`	Longitude in decimal degrees
`name`	`String`	`"<NONAME>"`	Name of the instance, visible in the event object

Event properties

Property	Type	Description
`event.sunrise`	`String`	Sunrise time in `HH:MM` format
`event.sunset`	`String`	Sunset time in `HH:MM` format
`event.latitude`	`Number`	Configured latitude
`event.longitude`	`Number`	Configured longitude
`event.date`	`String`	The date the times apply to
`event.name`	`String`	The instance name
`event.text`	`String`	Descriptive text with all the information

var sun1 = new scSunriseSet.SunRiseSetCheck(59.33, 18.07, "Stockholm");
sun1.getEventTarget().onDataAvailable = function(event)
{
    Debug.Print(event.text);
    // Example: "Check name: Stockholm, Sunrise: 06:15, sunset: 20:43 local time,
    //           for location latitude: 59.33, longitude: 18.07, for date: 2024-06-18"

    // Use the times to control other functions, e.g. enabling night mode
    // if(System.Clock.Hour + ":" + System.Clock.Minute >= event.sunset) { ... }
}

Coordinates

Coordinates for Swedish cities can easily be found via Google Maps — right-click a location and select "What's here?".

The script¶

Download scSunriseSet.js

    //***************************************//
    // The purpose of this script library
    //  is to calculate sunrise/sunset
    // times for a specific position(lat/long).
    // Version 1.0 (2022-06-13)
    // Copyright © 2022 Kentima AB. No rights reserved.
    //***************************************//

try
{    
    // Check for existance of script library 'scExtensions'
    if(typeof scExtensions == "undefined") 
    {
        throw new Error("Script library 'scExtensions' is missing."); //Script library is missing, we can't continue
    }

    //Calculate local time for sunrise and sunset, based on coordinates for latitude and longitude
    this.calculateSunRiseSet = function(lat, lon) 
    { 
        var altit = -35.0/60.0;
        var upper_limb = 1;

        var year = System.Clock.Year;
        var month = System.Clock.Month;
        var day = System.Clock.Day;

        /* Compute d of 12h local mean solar time */
        var d = (367*year-((7*(year+((month+9)/12)))/4)+((275*month)/9)+day-730530) + 0.5 - lon/360.0;

        /* Compute the local sidereal time of this moment */      
        var tmp1 = (180.0 + 356.0470 + 282.9404) + (0.9856002585 + 0.0000470935) * d;
        var tmp2 = tmp1 - 360.0 * Math.floor(tmp1/360.0);
        var tmp3 = tmp2 + 180.0 + lon;
        var sidtime = tmp3 - 360.0 * Math.floor(tmp3/360.0);

        /* Compute Sun's RA, Decl and distance at this moment */      
        //sun_RA_dec( d, &sRA, &sdec, &sr );
        //sunpos( d, &lon, r ) r=sr, lon lokal
        tmp1 = 356.0470 + 0.9856002585 * d;
        var M = tmp1 - 360.0 * Math.floor(tmp1 / 360.0);   
        var w = 282.9404 + 0.0000470935 * d;
        var e = 0.016709 - 0.000000001151 * d;
        var E = M + e * 180.0/3.14 * Math.sin(M* 3.14/180.0) * (1.0 + e * Math.cos(M*3.14/180.0));
        var x1 = Math.cos(E*3.14/180.0) - e;
        var y1 = Math.sqrt(1.0 - e*e) * Math.sin(E*3.14/180.0);
        var sr = Math.sqrt(x1*x1 + y1*y1);
        var v = Math.atan2(y1, x1) * 180.0/3.14;
        var lon2 = v + w;                   
        if (lon2 >= 360.0) lon2 -= 360.0;            


        var x = sr * Math.cos(lon2*3.14/180.0);
        var y = sr * Math.sin(lon2*3.14/180.0);
        var obl_ecl = 23.4393 - 0.0000003563 * d;
        var z = y * Math.sin(obl_ecl*3.14/180.0);
        y = y * Math.cos(obl_ecl*3.14/180.0);
        var sRA = Math.atan2(y, x) * 180.0/3.14;
        var sdec = Math.atan2(z, Math.sqrt(x*x + y*y)) * 180.0/3.14;

        /* Compute time when Sun is at south - in hours UT */      
        tmp1 = sidtime - sRA;
        var tsouth = 12.0 - (tmp1 - 360.0 * Math.floor(tmp1/360.0 + 0.5))/15.0;

        var sradius = 0.2666 / sr;

        if (upper_limb) altit -= sradius;

        var cost = (Math.sin(altit*3.14/180.0) - Math.sin(lat*3.14/180.0) * Math.sin(sdec*3.14/180.0)) / (Math.cos(lat*3.14/180.0) * Math.cos(sdec*3.14/180.0));

        var t;
        if (cost >= 1.0)
            t = 0.0;
        else if (cost <= -1.0)
            t = 12.0;
        else
            t = Math.acos(cost)/15.0 * 180.0/3.14;

        //UT
        var SunRising = tsouth - t + (System.Clock.TimezoneOffset/60);    //Adapt for UTC
        var SunSetting  = tsouth + t + (System.Clock.TimezoneOffset/60);;    //Adapt for UTC

        var sunRiseHour = Math.floor(SunRising);
        var sunRiseMinute = Math.round((SunRising - sunRiseHour) * 60);
        var sunSetHour = Math.floor(SunSetting);
        var sunSetMinute = Math.round((SunSetting - sunSetHour) * 60);

        //Create object to return
        var sunTime = new Object();
        sunTime["rise"] = ("0" + sunRiseHour).slice(-2) + ":" + ("0" + sunRiseMinute).slice(-2);
        sunTime["set"] = ("0" + sunSetHour).slice(-2) + ":" + ("0" + sunSetMinute).slice(-2);

        return sunTime;
    }

    //Create Sunrise sunset object
    this.SunRiseSetCheck = function(latitude, longitude, name)
    {
        try
        {
            var lat         = (typeof latitude == "undefined" || typeof latitude !== "number") ? 55.6405 : latitude; //Set default latitude value to 55.6405, if latitude parameter is missing
            var long        = (typeof longitude == "undefined" || typeof longitude !== "number") ? 13.2134 : longitude; //Set default latitude value to 13.2134, if latitude parameter is missing
            var n           = (typeof name == "undefined" || typeof name !== "string" || name == "") ? "<NONAME>" : name; //Set default name
            var eventTarget = new EventTarget(); //Create EventTarget on the object

            this.getEventTarget = function()
            {
                return eventTarget; // return eventTarget
            }

            //Create function for sending an Event
            var sendEvent = function(sunrise, sunset, latitude, longitude, date, name)
            {
                try
                {
                    var event = new Event(); //Create new Event object
                    event.initEvent("DataAvailable", true, true);

                    event.sunrise   = sunrise; //Store sunrise in the event
                    event.sunset    = sunset; //Store sunset in the event
                    event.latitude  = latitude; //Store latitude in the event
                    event.longitude = longitude; //Store longitude in the event
                    event.date      = date; //Store date on the event
                    event.name      = name; //Store name on the event
                    event.text      = "Check name: " + name + ", Sunrise: " + sunrise + ", sunset: " + sunset + " local time, for location latitude: " + latitude + ", longitude: " + longitude + ", for date: " + event.date; //Add optional text to the event

                    if(eventTarget.willTrigger("DataAvailable")) //Check if EventListener exists
                        eventTarget.dispatchEvent(event);
                    else
                        throw new Error("Event listener 'DataAvailable' is missing"); //Throw Error if EventListener is missing.
                }
                catch(e)
                {
                    Debug.Print("scSunRiseSet.SunRiseSetCheck.sendEvent(): " + e);
                }
            }

            //Function for getting new data
            this.getData = function()
            {
                try
                {
                    var sun = scSunriseSet.calculateSunRiseSet(lat, long); //Function will return a Struct object, containing to values(rise, set).
                    sendEvent(  sun.rise,   //Time for sunrise
                                sun.set,    //Time for sunset
                                lat,        //Latitude
                                long,       //Longitude
                                new Date().toLocaleDateString(), //Get todays' date
                                n);         //Name of instance
                }
                catch(e)
                {
                    Debug.Print("scSunRiseSet.SunRiseSunSetCheck.getData(): " + e);
                }
            }

            //Create Timer object
            var timer    = new Timer(1000, false); //Create new Timer object
            timer.parent = this; //Create reference to this object, to get access from Timer object
            timer.onTimeout = function()
            {
                try
                {
                    this.parent.getData(); //Execute getData() function
                    this.start(scExtensions.msLeftUntilMidnight()+60000); //Restart the timer to get an update at midnight
                }
                catch(e)
                {
                    Debug.Print("scSunRiseSet.SunRiseSunSetCheck.timer.onTImeout(): " + e);
                }
            }
        }
        catch(e)
        {
            Debug.Print("SunRiseSetCheck.timer.onTimeout(): " + e); //Catch any error from onTimeout function
        }
    }
}
catch(e)
{
    Debug.Print("scSunriseSet: " + e);
}