GARStoLL Class Reference

https://github.com/mil-oss/GARSutils MIT License More...

Static Public Member Functions
static String	getCenterKMLCoords (String GARS)
	Convert a GARS string to KML STRING representation of the center coordinates. More...
static String	getCenterJSONCoords (String GARS)
	Convert a GARS string to JSON representation of the center coordinates. More...
static String	getCenterCoords (String GARS)
	Convert a GARS string to STRING representation of the center coordinates. More...
static double[]	getCenterCoordsArray (String GARS)
	Convert a GARS string to double array containing latitude and longitude. More...
static double[]	getCornerCoordsArray (String GARS)
	Convert a GARS string to double array containing latitude and longitude coordinates of the lower left and upper right corners of the GARS tile. More...
static String	getCornerJSONCoords (String GARS)
	Convert a GARS string to JSON representation of the corner coordinates. More...
static String	getKMLLine (String GARS, String kmlColor, double kmlWidth)
	Convert a GARS String to a KML Placemark fragment representing the GARS tile as a line. More...
static String	getKMLPolygon (String GARS, String kmlColor, String kmlFillColor, double kmlWidth)
	Convert a GARS String to a KML Placemark fragment representing the GARS tile as a filled polygon. More...
static String	getKMLPoint (String GARS, String lblColor, double lblSize)
	Convert a GARS String to a KML Placemark fragment depicting the GARS string as a label in the center of the GARS tile. More...

Detailed Description

https://github.com/mil-oss/GARSutils MIT License

Author

marty

Member Function Documentation

getCenterCoords()

static String getCenterCoords ( String  GARS )

static

Convert a GARS string to STRING representation of the center coordinates.

If the GARS string is invalid then the string 'error' is returned.
If the conversion was successful the center point of the GARS tile is returned in the format latitude,longitude. Latitude and longitude are in decimal degrees separated by a comma.

A typical result string looks like the following:
12.34567,123.45678

Parameters

GARS

String

Returns

String

                                                      {
        double[] ll = getCenterCoordsArray(GARS);
        if (ll.length != 2) {
            return "error";
        }
        StringBuilder latlon = new StringBuilder();
        latlon.append(ll[0]).append(",").append(ll[1]);
 
        return latlon.toString();
 
    }//getCenterCoords    

References GARStoLL.getCenterCoordsArray().

Referenced by GARStoLL.getCenterJSONCoords().

getCenterCoordsArray()

static double [] getCenterCoordsArray ( String  GARS )

static

Convert a GARS string to double array containing latitude and longitude.

This code is a port of the NGA's geotrans cpp routines from the GEOTRANS 3.5 SDK: http://earth-info.nga.mil/GandG/geotrans/

If the GARS string is invalid then the returned array has a length of 1 and the first and only value will be -360
If the conversion was successful the center point of the GARS tile is returned as decimal degrees. The first value (index 0) holds latitude, the second value is longitude.
Check the length of the array for error checking, the length of a successful transformation will equal 2.

Parameters

GARS

String

Returns

double[]

                                                             {
        int GARS_MINIMUM = 5;          // Minimum number of chars for GARS  
        int GARS_MAXIMUM = 7;          // Maximum number of chars for GARS  
        int LETTER_A_OFFSET = 65;      // Letter A offset in character set
        double MIN_PER_DEG = 60;       // Number of minutes per degree
        double[] ll = new double[2];
 
        /* A = 0, B = 1, C = 2, D = 3, E = 4, F = 5, G = 6, H = 7             */
        int LETTER_I = 8;                /* ARRAY INDEX FOR LETTER I          */
        /* J = 9, K = 10, L = 11, M = 12, N = 13                              */
 
        int LETTER_O = 14;              /* ARRAY INDEX FOR LETTER O           */
        /* P = 15, Q = 16, R = 17, S = 18, T = 19, U = 20, V = 21,            */
        /* W = 22, X = 23, Y = 24, Z = 25                                     */
 
        char _1 = '1';
        char _2 = '2';
        char _3 = '3';
        char _4 = '4';
        char _5 = '5';
        char _6 = '6';
        char _7 = '7';
        char _8 = '8';
        char _9 = '9';
 
        char[] GARSString = GARS.toCharArray();
        int lat = 0;
        int lon = 1;
        int gars_length = GARSString.length;
        if ((gars_length < GARS_MINIMUM) || (gars_length > GARS_MAXIMUM)) {
            ll = new double[1];
            ll[0] = -360;
            return ll;
        }
        String ew_string = "";
        int index = 0;
        while (isDigit(GARSString[index])) {
            ew_string += GARSString[index];
            index++;
        }
        //ERROR Checking longitude band, must be 3 digits
        if (index != 3) {
            ll = new double[1];
            ll[0] = -360;
            return ll;
        }
 
        /* Get 30 minute east/west value, 1-720 */
        Integer ew_value;
        ew_value = Integer.parseInt(ew_string);
 
        char letter = ' ';
        letter = GARSString[index];
        if (!Character.isLetter(letter)) {
            ll = new double[1];
            ll[0] = -360;
            return ll; // The latitude band must be a letter
        }
 
        /* Get first 30 minute north/south letter, A-Q */
        int[] ns_str = new int[3];
        ns_str[0] = letter - LETTER_A_OFFSET;
        letter = GARSString[++index];
        if (!Character.isLetter(letter)) {
            ll = new double[1];
            ll[0] = -360;
            return ll; // The latitude band must be a letter
        }
        /* Get second 30 minute north/south letter, A-Z */
        ns_str[1] = letter - LETTER_A_OFFSET;
 
        char _15_minute_value = 0;
        char _5_minute_value = 0;
        if (index + 1 < gars_length) {
            /* Get 15 minute quadrant value, 1-4 */
            _15_minute_value = GARSString[++index];
            //System.out.println("GARS " + GARS + " 15 MINUTE VAL: " + _15_minute_value);
            if (!isDigit(_15_minute_value) || _15_minute_value < _1 || _15_minute_value > _4) {
                ll = new double[1];
                ll[0] = -360;
                return ll;
            } else {
                if (index + 1 < gars_length) {
                    /* Get 5 minute quadrant value, 1-9 */
                    _5_minute_value = GARSString[++index];
                    //System.out.println("GARS " + GARS + " 5 MINUTE VAL: " + _5_minute_value);
                    if (!isDigit(_5_minute_value) || _5_minute_value < _1 || _5_minute_value > _9) {
                        ll = new double[1];
                        ll[0] = -360;
                        return ll;
                    }
                }
            }
        }//
 
        double longitude = (((ew_value - 1.0) / 2.0) - 180.0);
        /* Letter I and O are invalid */
        if (ns_str[0] >= LETTER_O) {
            ns_str[0]--;
        }
        if (ns_str[0] >= LETTER_I) {
            ns_str[0]--;
        }
 
        if (ns_str[1] >= LETTER_O) {
            ns_str[1]--;
        }
        if (ns_str[1] >= LETTER_I) {
            ns_str[1]--;
        }
 
        double latitude = ((-90.0 + (ns_str[0] * 12.0)) + (ns_str[1] / 2.0));
 
        double lat_minutes = 0.0, lon_minutes = 0.0;
 
        //Strings in switch not allowed in Java 6
        if (Character.toString(_15_minute_value).equals("1")) {
            lat_minutes = 15.0;
        } else if (Character.toString(_15_minute_value).equals("4")) {
            lon_minutes = 15.0;
        } else if (Character.toString(_15_minute_value).equals("2")) {
            lat_minutes = 15.0;
            lon_minutes = 15.0;
        }
 
        if (Character.toString(_5_minute_value).equals("4")) {
            lat_minutes += 5.0;
        } else if (Character.toString(_5_minute_value).equals("1")) {
            lat_minutes += 10.0;
        } else if (Character.toString(_5_minute_value).equals("8")) {
            lon_minutes += 5.0;
        } else if (Character.toString(_5_minute_value).equals("5")) {
            lon_minutes += 5.0;
            lat_minutes += 5.0;
        } else if (Character.toString(_5_minute_value).equals("2")) {
            lon_minutes += 5.0;
            lat_minutes += 10.0;
        } else if (Character.toString(_5_minute_value).equals("9")) {
            lon_minutes += 10.0;
        } else if (Character.toString(_5_minute_value).equals("6")) {
            lon_minutes += 10.0;
            lat_minutes += 5.0;
        } else if (Character.toString(_5_minute_value).equals("3")) {
            lon_minutes += 10.0;
            lat_minutes += 10.0;
        }
 
        /* Add these values to force the reference point to be the center of the box */
        if (_5_minute_value != 0) {
            lat_minutes += 2.5;
            lon_minutes += 2.5;
        } else if (_15_minute_value != 0) {
            lat_minutes += 7.5;
            lon_minutes += 7.5;
        } else {
            lat_minutes += 15.0;
            lon_minutes += 15.0;
        }
        latitude += lat_minutes / MIN_PER_DEG;
        longitude += lon_minutes / MIN_PER_DEG;
        ll[0] = latitude;
        ll[1] = longitude;
        return ll;
 
    }//getCenterCoordsArray        

Referenced by GARStoLL.getCenterCoords(), GARStoLL.getCenterKMLCoords(), and GARStoLL.getKMLPoint().

getCenterJSONCoords()

static String getCenterJSONCoords ( String  GARS )

static

Convert a GARS string to JSON representation of the center coordinates.

The JSON is will always return a status key with either "error" or "success".
If the conversion was successful then latitude and longitude keys are returned with decimal degrees values for the center point of the GARS tile.

A typical JSON string looks like the following:
{"status":"success","latitude":12.34567,"longitude":123.45678}

Parameters

GARS

String

Returns

JSON String

                                                          {
        String latlon = getCenterCoords(GARS);
        if (latlon.toLowerCase().contains("error")) {
            return "{\"status\":\"error\"}";
        }
        String[] ll = latlon.split(",");
        StringBuilder json = new StringBuilder();
        json.append("{\"status\":\"success\",\"latitude\":").append(ll[0]).append(",\"longitude\":").append(ll[1]).append("}");
        return json.toString();
 
    }//getCenterJSONCoords    

References GARStoLL.getCenterCoords().

getCenterKMLCoords()

static String getCenterKMLCoords ( String  GARS )

static

Convert a GARS string to KML STRING representation of the center coordinates.

If the GARS string is invalid then an empty string is returned.
If the conversion was successful the center point of the GARS tile is returned in the format longitude,latitude. The coordinates are in decimal degrees separated by a comma.
Note: KML simply reverses the order of the coordinates and returns longitude first.

A typical result string looks like the following:
123.45678,12.34567

Parameters

GARS

String

Returns

String

                                                         {
        double[] ll = getCenterCoordsArray(GARS);
        if (ll.length != 2) {
            return "";
        }
        StringBuilder latlon = new StringBuilder();
        latlon.append(ll[1]).append(",").append(ll[0]);
 
        return latlon.toString();
    }//getCenterKmlCoords

References GARStoLL.getCenterCoordsArray().

getCornerCoordsArray()

static double [] getCornerCoordsArray ( String  GARS )

static

Convert a GARS string to double array containing latitude and longitude coordinates of the lower left and upper right corners of the GARS tile.

This code is a port of the NGA's geotrans cpp routines from the GEOTRANS 3.5 SDK: http://earth-info.nga.mil/GandG/geotrans/

If the GARS string is invalid then the returned array has a length of 1 and the first and only value will be -360
If the conversion was successful the corner points of the GARS tile is returned as decimal degrees. The first value (index 0) holds latitude, the second value is longitude of the lower left corner. The third and fourth values hold the latitude and longitude of the upper right corner.
Check the length of the array for error checking, the length of a successful transformation will equal 4.

Parameters

GARS

Returns

double[]

                                                             {
        int GARS_MINIMUM = 5;          // Minimum number of chars for GARS  
        int GARS_MAXIMUM = 7;          // Maximum number of chars for GARS  
        int LETTER_A_OFFSET = 65;      // Letter A offset in character set
        double MIN_PER_DEG = 60;       // Number of minutes per degree
        double[] ll = new double[4];
 
        /* A = 0, B = 1, C = 2, D = 3, E = 4, F = 5, G = 6, H = 7             */
        int LETTER_I = 8;                /* ARRAY INDEX FOR LETTER I          */
        /* J = 9, K = 10, L = 11, M = 12, N = 13                              */
 
        int LETTER_O = 14;              /* ARRAY INDEX FOR LETTER O           */
        /* P = 15, Q = 16, R = 17, S = 18, T = 19, U = 20, V = 21,            */
        /* W = 22, X = 23, Y = 24, Z = 25                                     */
 
        char _1 = '1';
        char _2 = '2';
        char _3 = '3';
        char _4 = '4';
        char _5 = '5';
        char _6 = '6';
        char _7 = '7';
        char _8 = '8';
        char _9 = '9';
 
        char[] GARSString = GARS.toCharArray();
        int lat = 0;
        int lon = 1;
        int gars_length = GARSString.length;
        if ((gars_length < GARS_MINIMUM) || (gars_length > GARS_MAXIMUM)) {
            ll = new double[1];
            ll[0] = -360;
            return ll;
        }
        String ew_string = "";
        int index = 0;
        while (isDigit(GARSString[index])) {
            ew_string += GARSString[index];
            index++;
        }
        //ERROR Checking longitude band, must be 3 digits
        if (index != 3) {
            ll = new double[1];
            ll[0] = -360;
            return ll;
        }
 
        /* Get 30 minute east/west value, 1-720 */
        Integer ew_value;
        ew_value = Integer.parseInt(ew_string);
 
        char letter = ' ';
        letter = GARSString[index];
        if (!Character.isLetter(letter)) {
            ll = new double[1];
            ll[0] = -360;
            return ll; // The latitude band must be a letter
        }
 
        /* Get first 30 minute north/south letter, A-Q */
        int[] ns_str = new int[3];
        ns_str[0] = letter - LETTER_A_OFFSET;
        letter = GARSString[++index];
        if (!Character.isLetter(letter)) {
            ll = new double[1];
            ll[0] = -360;
            return ll; // The latitude band must be a letter
        }
        /* Get second 30 minute north/south letter, A-Z */
        ns_str[1] = letter - LETTER_A_OFFSET;
 
        char _15_minute_value = 0;
        char _5_minute_value = 0;
        if (index + 1 < gars_length) {
            /* Get 15 minute quadrant value, 1-4 */
            _15_minute_value = GARSString[++index];
            if (!isDigit(_15_minute_value) || _15_minute_value < _1 || _15_minute_value > _4) {
                ll = new double[1];
                ll[0] = -360;
                return ll;
            } else {
                if (index + 1 < gars_length) {
                    /* Get 5 minute quadrant value, 1-9 */
                    _5_minute_value = GARSString[++index];
                    if (!isDigit(_5_minute_value) || _5_minute_value < _1 || _5_minute_value > _9) {
                        ll = new double[1];
                        ll[0] = -360;
                        return ll;
                    }
                }
            }
        }//
 
        double longitude = (((ew_value - 1.0) / 2.0) - 180.0);
        /* Letter I and O are invalid */
        if (ns_str[0] >= LETTER_O) {
            ns_str[0]--;
        }
        if (ns_str[0] >= LETTER_I) {
            ns_str[0]--;
        }
 
        if (ns_str[1] >= LETTER_O) {
            ns_str[1]--;
        }
        if (ns_str[1] >= LETTER_I) {
            ns_str[1]--;
        }
 
        double latitude = ((-90.0 + (ns_str[0] * 12.0)) + (ns_str[1] / 2.0));
 
        double lat_minutes = 0.0, lon_minutes = 0.0;
 
        //Strings in switch not allowed in Java 6
        if (Character.toString(_15_minute_value).equals("1")) {
            lat_minutes = 15.0;
        } else if (Character.toString(_15_minute_value).equals("4")) {
            lon_minutes = 15.0;
        } else if (Character.toString(_15_minute_value).equals("2")) {
            lat_minutes = 15.0;
            lon_minutes = 15.0;
        }
 
        if (Character.toString(_5_minute_value).equals("4")) {
            lat_minutes += 5.0;
        } else if (Character.toString(_5_minute_value).equals("1")) {
            lat_minutes += 10.0;
        } else if (Character.toString(_5_minute_value).equals("8")) {
            lon_minutes += 5.0;
        } else if (Character.toString(_5_minute_value).equals("5")) {
            lon_minutes += 5.0;
            lat_minutes += 5.0;
        } else if (Character.toString(_5_minute_value).equals("2")) {
            lon_minutes += 5.0;
            lat_minutes += 10.0;
        } else if (Character.toString(_5_minute_value).equals("9")) {
            lon_minutes += 10.0;
        } else if (Character.toString(_5_minute_value).equals("6")) {
            lon_minutes += 10.0;
            lat_minutes += 5.0;
        } else if (Character.toString(_5_minute_value).equals("3")) {
            lon_minutes += 10.0;
            lat_minutes += 10.0;
        }
 
        // Store lower left coordinates
        ll[0] = latitude + lat_minutes / MIN_PER_DEG;
        ll[1] = longitude + lon_minutes / MIN_PER_DEG;;
 
        /* Add these values to force the reference point to be the upper right corner of the box */
        if (_5_minute_value != 0) {
            lat_minutes += 5.0;
            lon_minutes += 5.0;
        } else if (_15_minute_value != 0) {
            lat_minutes += 15.0;
            lon_minutes += 15.0;
        } else {
            lat_minutes += 30.0;
            lon_minutes += 30.0;
        }
        latitude += lat_minutes / MIN_PER_DEG;
        longitude += lon_minutes / MIN_PER_DEG;
        ll[2] = latitude;
        ll[3] = longitude;
        return ll;
 
    }//getCornerCoordsArray    

Referenced by GARStoLL.getCornerJSONCoords(), GARStoLL.getKMLLine(), and GARStoLL.getKMLPolygon().

getCornerJSONCoords()

static String getCornerJSONCoords ( String  GARS )

static

Convert a GARS string to JSON representation of the corner coordinates.

The JSON is will always return a status key with either "error" or "success".
If the conversion was successful then latitude and longitude keys are returned with decimal degrees values for the lower left and upper right corners of the GARS tile.
The corner coordinates are referenced by the keys "lowerleft" and "upperright" and are an object containing a "latitude" and "longitude" coordinate.

A typical JSON string looks like the following:
{
"status": "success",
"lowerleft": { "latitude":-33.4167, "longitude":-70.4167 },
"upperright": { "latitude":-33.3336, "longitude":-70.3333 }
}

Parameters

GARS

Returns

JSON string

                                                          {
        double[] ll = getCornerCoordsArray(GARS);
        if (ll.length < 4) {
            return "{\"status\":\"error\"}";
        }
        StringBuilder json = new StringBuilder();
        json.append("{\"status\":\"success\",");
        json.append("\"lowerleft\":{\"latitude\":").append(ll[0]).append(",\"longitude\":").append(ll[1]).append("},");
        json.append("\"upperright\":{\"latitude\":").append(ll[2]).append(",\"longitude\":").append(ll[3]).append("}");
        json.append("}");
 
        return json.toString();
 
    }//getCornerJSONCoords  

References GARStoLL.getCornerCoordsArray().

getKMLLine()

static String getKMLLine ( String  GARS, String  kmlColor, double  kmlWidth  )

static

Convert a GARS String to a KML Placemark fragment representing the GARS tile as a line.

If the GARS string is invalid then an empty string is returned.

kmlColor is a string in the format of aabbggrr, where aa=alpha (00 to ff); bb=blue (00 to ff); gg=green (00 to ff); rr=red (00 to ff)
Example: blue color with 50 percent opacity = 7fff0000

kmlWidth is an integer representing the line width.

Parameters

GARS
kmlColor	the color of the line
kmlWidth	the width of the line

Returns

KML Placemark fragment

                                                                                   {
        StringBuilder kml = new StringBuilder();
        double[] ll = getCornerCoordsArray(GARS);
        if (ll.length < 4) {
            return "";
        }
        kml.append("<Placemark> \n"
                + " <LineString>\n"
                + "  <coordinates>\n");
        kml.append(ll[1]).append(",").append(ll[0]).append(",0.0\n");
        kml.append(ll[1]).append(",").append(ll[2]).append(",0.0\n");
        kml.append(ll[3]).append(",").append(ll[2]).append(",0.0\n");
        kml.append(ll[3]).append(",").append(ll[0]).append(",0.0\n");
        kml.append(ll[1]).append(",").append(ll[0]).append(",0.0\n"
                + "  </coordinates>\n"
                + " </LineString>\n"
                + " <Style>\n"
                + "  <LineStyle>\n"
                + "   <color>#");
        kml.append(kmlColor);
        kml.append("</color>\n"
                + "   <width>");
        kml.append(kmlWidth);
        kml.append("</width>\n"
                + "  </LineStyle> \n"
                + " </Style>\n"
                + "</Placemark>");
        return kml.toString();
    }//getKMLLine

References GARStoLL.getCornerCoordsArray().

getKMLPoint()

static String getKMLPoint ( String  GARS, String  lblColor, double  lblSize  )

static

Convert a GARS String to a KML Placemark fragment depicting the GARS string as a label in the center of the GARS tile.

KML colors are a string in the format of aabbggrr, where aa=alpha (00 to ff); bb=blue (00 to ff); gg=green (00 to ff); rr=red (00 to ff)
Example: blue color with 50 percent opacity = 7fff0000

Parameters

GARS
lblColor	the color of the text
lblSize	the size of the text (as a ratio to the normal size of 1.0)

Returns

KML Placemark fragment

                                                                                   {
        double[] ll = getCenterCoordsArray(GARS);
        if (ll.length != 2) {
            return "";
        }
        StringBuilder latlon = new StringBuilder();
        latlon.append(ll[1]).append(",").append(ll[0]);
 
        StringBuilder kml = new StringBuilder();
        kml.append("    <Placemark>\n"
                + "             <name>" + GARS + "</name>\n"
                + "     <Style>\n"
                + "             <IconStyle>\n"
                + "                     <scale>0</scale>\n"
                + "             </IconStyle>\n"
                + "             <LabelStyle>\n"
                + "                     <color>" + lblColor + "</color>\n"
                + "                     <scale>" + lblSize + "</scale>"
                + "             </LabelStyle>"
                + "     </Style>\n"
                + "             <Point>\n"
                + "\n"
                + "                     <coordinates>" + latlon + ",0</coordinates>\n"
                + "             </Point>\n"
                + "     </Placemark>");
        return kml.toString();
    }//getKMLPoint

References GARStoLL.getCenterCoordsArray().

getKMLPolygon()

static String getKMLPolygon ( String  GARS, String  kmlColor, String  kmlFillColor, double  kmlWidth  )

static

Convert a GARS String to a KML Placemark fragment representing the GARS tile as a filled polygon.

If the GARS string is invalid then an empty string is returned.

KML colors are a string in the format of aabbggrr, where aa=alpha (00 to ff); bb=blue (00 to ff); gg=green (00 to ff); rr=red (00 to ff)
Example: blue color with 50 percent opacity = 7fff0000

kmlWidth is an integer representing the line width.

Parameters

GARS
kmlColor	the color of the line
kmlFillColor	the color of the polygon's fill
kmlWidth	the width of the line

Returns

KML Placemark fragment

                                                                                                           {
        StringBuilder kml = new StringBuilder();
        double[] ll = getCornerCoordsArray(GARS);
        if (ll.length < 4) {
            return "";
        }
        kml.append("<Placemark> \n"
                + "<Polygon>\n"
                + "<tessellate>1</tessellate>\n"
                + "<outerBoundaryIs>\n"
                + "<LinearRing>\n"
                + "  <coordinates>\n");
        kml.append(ll[1]).append(",").append(ll[0]).append(",0.0\n");
        kml.append(ll[1]).append(",").append(ll[2]).append(",0.0\n");
        kml.append(ll[3]).append(",").append(ll[2]).append(",0.0\n");
        kml.append(ll[3]).append(",").append(ll[0]).append(",0.0\n");
        kml.append(ll[1]).append(",").append(ll[0]).append(",0.0\n"
                + "  </coordinates>\n"
                + "</LinearRing>\n"
                + "</outerBoundaryIs>\n"
                + "</Polygon>\n"
                + " <Style>\n"
                + "  <LineStyle>\n"
                + "   <color>#");
        kml.append(kmlColor);
        kml.append("</color>\n"
                + "   <width>");
        kml.append(kmlWidth);
        kml.append("</width>\n"
                + "  </LineStyle> \n"
                + "  <PolyStyle>\n"
                + "   <color>#");
        kml.append(kmlFillColor);
        kml.append("</color>\n"
                + "  </PolyStyle> \n"
                + " </Style>\n"
                + "</Placemark>");
        return kml.toString();
    }//getKMLLine

References GARStoLL.getCornerCoordsArray().