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Diffstat (limited to 'includes/phpcoord/phpcoord-2.3.php')
| -rw-r--r-- | includes/phpcoord/phpcoord-2.3.php | 785 |
1 files changed, 0 insertions, 785 deletions
diff --git a/includes/phpcoord/phpcoord-2.3.php b/includes/phpcoord/phpcoord-2.3.php deleted file mode 100644 index edac27a..0000000 --- a/includes/phpcoord/phpcoord-2.3.php +++ /dev/null @@ -1,785 +0,0 @@ -<?php - -/**-------------------------------------------------------------------------- - * PHPcoord - * phpcoord.php - * - * @package kernel - */ - - // (c) 2005 Jonathan Stott - // - // Created on 11-Aug-2005 - // - // 2.3 - 24 Aug 2006 - // - Changed OSRef->toSixFigureString() so that the eastings and northings - // are rounded rather than floored. - // 2.2 - 11 Feb 2006 - // - Used different algorithm for calculating distance between latitudes - // and longitudes - fixes a number of problems with distance calculations - // 2.1 - 22 Dec 2005 - // - Added getOSRefFromSixFigureReference function - // 2.0 - 21 Dec 2005 - // - Completely different object design - conversion functions now through - // objects rather than static functions - // - Updated comments and documentation - // 1.1 - 11 Sep 2005 - // - Added OSGB36/WGS84 data conversions - // 1.0 - 11 Aug 2005 - // - Initial version - //-------------------------------------------------------------------------- - - -/** - * LatLng - * - * @package kernel - */ - class LatLng { - - var $lat; - var $lng; - - - /** - * Create a new LatLng object from the given latitude and longitude - * - * @param lat latitude - * @param lng longitude - */ - function LatLng($lat, $lng) { - $this->lat = $lat; - $this->lng = $lng; - } - - - /** - * Return a string representation of this LatLng object - * - * @return a string representation of this LatLng object - */ - function toString() { - return "(" . $this->lat . ", " . $this->lng . ")"; - } - - - /** - * Calculate the surface distance between this LatLng object and the one - * passed in as a parameter. - * - * @param to a LatLng object to measure the surface distance to - * @return the surface distance - */ - function distance($to) { - $er = 6366.707; - - $latFrom = deg2rad($this->lat); - $latTo = deg2rad($to->lat); - $lngFrom = deg2rad($this->lng); - $lngTo = deg2rad($to->lng); - - $x1 = $er * cos($lngFrom) * sin($latFrom); - $y1 = $er * sin($lngFrom) * sin($latFrom); - $z1 = $er * cos($latFrom); - - $x2 = $er * cos($lngTo) * sin($latTo); - $y2 = $er * sin($lngTo) * sin($latTo); - $z2 = $er * cos($latTo); - - $d = acos(sin($latFrom)*sin($latTo) + cos($latFrom)*cos($latTo)*cos($lngTo-$lngFrom)) * $er; - - return $d; - } - - - /** - * Convert this LatLng object from OSGB36 datum to WGS84 datum. - */ - function OSGB36ToWGS84() { - $airy1830 = new RefEll(6377563.396, 6356256.909); - $a = $airy1830->maj; - $b = $airy1830->min; - $eSquared = $airy1830->ecc; - $phi = deg2rad($this->lat); - $lambda = deg2rad($this->lng); - $v = $a / (sqrt(1 - $eSquared * sinSquared($phi))); - $H = 0; // height - $x = ($v + $H) * cos($phi) * cos($lambda); - $y = ($v + $H) * cos($phi) * sin($lambda); - $z = ((1 - $eSquared) * $v + $H) * sin($phi); - - $tx = 446.448; - $ty = -124.157; - $tz = 542.060; - $s = -0.0000204894; - $rx = deg2rad( 0.00004172222); - $ry = deg2rad( 0.00006861111); - $rz = deg2rad( 0.00023391666); - - $xB = $tx + ($x * (1 + $s)) + (-$rx * $y) + ($ry * $z); - $yB = $ty + ($rz * $x) + ($y * (1 + $s)) + (-$rx * $z); - $zB = $tz + (-$ry * $x) + ($rx * $y) + ($z * (1 + $s)); - - $wgs84 = new RefEll(6378137.000, 6356752.3141); - $a = $wgs84->maj; - $b = $wgs84->min; - $eSquared = $wgs84->ecc; - - $lambdaB = rad2deg(atan($yB / $xB)); - $p = sqrt(($xB * $xB) + ($yB * $yB)); - $phiN = atan($zB / ($p * (1 - $eSquared))); - for ($i = 1; $i < 10; $i++) { - $v = $a / (sqrt(1 - $eSquared * sinSquared($phiN))); - $phiN1 = atan(($zB + ($eSquared * $v * sin($phiN))) / $p); - $phiN = $phiN1; - } - - $phiB = rad2deg($phiN); - - $this->lat = $phiB; - $this->lng = $lambdaB; - } - - - /** - * Convert this LatLng object from WGS84 datum to OSGB36 datum. - */ - function WGS84ToOSGB36() { - $wgs84 = new RefEll(6378137.000, 6356752.3141); - $a = $wgs84->maj; - $b = $wgs84->min; - $eSquared = $wgs84->ecc; - $phi = deg2rad($this->lat); - $lambda = deg2rad($this->lng); - $v = $a / (sqrt(1 - $eSquared * sinSquared($phi))); - $H = 0; // height - $x = ($v + $H) * cos($phi) * cos($lambda); - $y = ($v + $H) * cos($phi) * sin($lambda); - $z = ((1 - $eSquared) * $v + $H) * sin($phi); - - $tx = -446.448; - $ty = 124.157; - $tz = -542.060; - $s = 0.0000204894; - $rx = deg2rad(-0.00004172222); - $ry = deg2rad(-0.00006861111); - $rz = deg2rad(-0.00023391666); - - $xB = $tx + ($x * (1 + $s)) + (-$rx * $y) + ($ry * $z); - $yB = $ty + ($rz * $x) + ($y * (1 + $s)) + (-$rx * $z); - $zB = $tz + (-$ry * $x) + ($rx * $y) + ($z * (1 + $s)); - - $airy1830 = new RefEll(6377563.396, 6356256.909); - $a = $airy1830->maj; - $b = $airy1830->min; - $eSquared = $airy1830->ecc; - - $lambdaB = rad2deg(atan($yB / $xB)); - $p = sqrt(($xB * $xB) + ($yB * $yB)); - $phiN = atan($zB / ($p * (1 - $eSquared))); - for ($i = 1; $i < 10; $i++) { - $v = $a / (sqrt(1 - $eSquared * sinSquared($phiN))); - $phiN1 = atan(($zB + ($eSquared * $v * sin($phiN))) / $p); - $phiN = $phiN1; - } - - $phiB = rad2deg($phiN); - - $this->lat = $phiB; - $this->lng = $lambdaB; - } - - - /** - * Convert this LatLng object into an OSGB grid reference. Note that this - * function does not take into account the bounds of the OSGB grid - - * beyond the bounds of the OSGB grid, the resulting OSRef object has no - * meaning - * - * @return the converted OSGB grid reference - */ - function toOSRef() { - $airy1830 = new RefEll(6377563.396, 6356256.909); - $OSGB_F0 = 0.9996012717; - $N0 = -100000.0; - $E0 = 400000.0; - $phi0 = deg2rad(49.0); - $lambda0 = deg2rad(-2.0); - $a = $airy1830->maj; - $b = $airy1830->min; - $eSquared = $airy1830->ecc; - $phi = deg2rad($this->lat); - $lambda = deg2rad($this->lng); - $E = 0.0; - $N = 0.0; - $n = ($a - $b) / ($a + $b); - $v = $a * $OSGB_F0 * pow(1.0 - $eSquared * sinSquared($phi), -0.5); - $rho = - $a * $OSGB_F0 * (1.0 - $eSquared) * pow(1.0 - $eSquared * sinSquared($phi), -1.5); - $etaSquared = ($v / $rho) - 1.0; - $M = - ($b * $OSGB_F0) - * (((1 + $n + ((5.0 / 4.0) * $n * $n) + ((5.0 / 4.0) * $n * $n * $n)) - * ($phi - $phi0)) - - (((3 * $n) + (3 * $n * $n) + ((21.0 / 8.0) * $n * $n * $n)) - * sin($phi - $phi0) - * cos($phi + $phi0)) - + ((((15.0 / 8.0) * $n * $n) + ((15.0 / 8.0) * $n * $n * $n)) - * sin(2.0 * ($phi - $phi0)) - * cos(2.0 * ($phi + $phi0))) - - (((35.0 / 24.0) * $n * $n * $n) - * sin(3.0 * ($phi - $phi0)) - * cos(3.0 * ($phi + $phi0)))); - $I = $M + $N0; - $II = ($v / 2.0) * sin($phi) * cos($phi); - $III = - ($v / 24.0) - * sin($phi) - * pow(cos($phi), 3.0) - * (5.0 - tanSquared($phi) + (9.0 * $etaSquared)); - $IIIA = - ($v / 720.0) - * sin($phi) - * pow(cos($phi), 5.0) - * (61.0 - (58.0 * tanSquared($phi)) + pow(tan($phi), 4.0)); - $IV = $v * cos($phi); - $V = ($v / 6.0) * pow(cos($phi), 3.0) * (($v / $rho) - tanSquared($phi)); - $VI = - ($v / 120.0) - * pow(cos($phi), 5.0) - * (5.0 - - (18.0 * tanSquared($phi)) - + (pow(tan($phi), 4.0)) - + (14 * $etaSquared) - - (58 * tanSquared($phi) * $etaSquared)); - - $N = - $I - + ($II * pow($lambda - $lambda0, 2.0)) - + ($III * pow($lambda - $lambda0, 4.0)) - + ($IIIA * pow($lambda - $lambda0, 6.0)); - $E = - $E0 - + ($IV * ($lambda - $lambda0)) - + ($V * pow($lambda - $lambda0, 3.0)) - + ($VI * pow($lambda - $lambda0, 5.0)); - - return new OSRef($E, $N); - } - - - /** - * Convert a latitude and longitude to an UTM reference - * - * @return the converted UTM reference - */ - function toUTMRef() { - $wgs84 = new RefEll(6378137, 6356752.314); - $UTM_F0 = 0.9996; - $a = $wgs84->maj; - $eSquared = $wgs84->ecc; - $longitude = $this->lng; - $latitude = $this->lat; - - $latitudeRad = $latitude * (pi() / 180.0); - $longitudeRad = $longitude * (pi() / 180.0); - $longitudeZone = (int) (($longitude + 180.0) / 6.0) + 1; - - // Special zone for Norway - if ($latitude >= 56.0 - && $latitude < 64.0 - && $longitude >= 3.0 - && $longitude < 12.0) { - $longitudeZone = 32; - } - - // Special zones for Svalbard - if ($latitude >= 72.0 && $latitude < 84.0) { - if ($longitude >= 0.0 && $longitude < 9.0) { - $longitudeZone = 31; - } else if ($longitude >= 9.0 && $longitude < 21.0) { - $longitudeZone = 33; - } else if ($longitude >= 21.0 && $longitude < 33.0) { - $longitudeZone = 35; - } else if ($longitude >= 33.0 && $longitude < 42.0) { - $longitudeZone = 37; - } - } - - $longitudeOrigin = ($longitudeZone - 1) * 6 - 180 + 3; - $longitudeOriginRad = $longitudeOrigin * (pi() / 180.0); - - $UTMZone = getUTMLatitudeZoneLetter($latitude); - - $ePrimeSquared = ($eSquared) / (1 - $eSquared); - - $n = $a / sqrt(1 - $eSquared * sin($latitudeRad) * sin($latitudeRad)); - $t = tan($latitudeRad) * tan($latitudeRad); - $c = $ePrimeSquared * cos($latitudeRad) * cos($latitudeRad); - $A = cos($latitudeRad) * ($longitudeRad - $longitudeOriginRad); - - $M = - $a - * ((1 - - $eSquared / 4 - - 3 * $eSquared * $eSquared / 64 - - 5 * $eSquared * $eSquared * $eSquared / 256) - * $latitudeRad - - (3 * $eSquared / 8 - + 3 * $eSquared * $eSquared / 32 - + 45 * $eSquared * $eSquared * $eSquared / 1024) - * sin(2 * $latitudeRad) - + (15 * $eSquared * $eSquared / 256 - + 45 * $eSquared * $eSquared * $eSquared / 1024) - * sin(4 * $latitudeRad) - - (35 * $eSquared * $eSquared * $eSquared / 3072) - * sin(6 * $latitudeRad)); - - $UTMEasting = - (double) ($UTM_F0 - * $n - * ($A - + (1 - $t + $c) * pow($A, 3.0) / 6 - + (5 - 18 * $t + $t * $t + 72 * $c - 58 * $ePrimeSquared) - * pow($A, 5.0) - / 120) - + 500000.0); - - $UTMNorthing = - (double) ($UTM_F0 - * ($M - + $n - * tan($latitudeRad) - * ($A * $A / 2 - + (5 - $t + (9 * $c) + (4 * $c * $c)) * pow($A, 4.0) / 24 - + (61 - (58 * $t) + ($t * $t) + (600 * $c) - (330 * $ePrimeSquared)) - * pow($A, 6.0) - / 720))); - - // Adjust for the southern hemisphere - if ($latitude < 0) { - $UTMNorthing += 10000000.0; - } - - return new UTMRef($UTMEasting, $UTMNorthing, $UTMZone, $longitudeZone); - } - } - -/** - * OSRef - * References given with OSRef are accurate to 1m. - * - * @package kernel - */ - class OSRef { - - var $easting; - var $northing; - - - /** - * Create a new OSRef object representing an OSGB grid reference. Note - * that the parameters for this constructor require eastings and - * northings with 1m accuracy and need to be absolute with respect to - * the whole of the British Grid. For example, to create an OSRef - * object from the six-figure grid reference TG514131, the easting would - * be 651400 and the northing would be 313100. - * - * Grid references with accuracy greater than 1m can be represented - * using floating point values for the easting and northing. For example, - * a value representing an easting or northing accurate to 1mm would be - * given as 651400.0001. - * - * @param easting the easting of the reference (with 1m accuracy) - * @param northing the northing of the reference (with 1m accuracy) - */ - function OSRef($easting, $northing) { - $this->easting = $easting; - $this->northing = $northing; - } - - - /** - * Convert this grid reference into a string showing the exact values - * of the easting and northing. - * - * @return - */ - function toString() { - return "(" . $this->easting . ", " . $this->northing . ")"; - } - - - /** - * Convert this grid reference into a string using a standard six-figure - * grid reference including the two-character designation for the 100km - * square. e.g. TG514131. - * - * @return - */ - function toSixFigureString() { - $hundredkmE = floor($this->easting / 100000); - $hundredkmN = floor($this->northing / 100000); - $firstLetter = ""; - if ($hundredkmN < 5) { - if ($hundredkmE < 5) { - $firstLetter = "S"; - } else { - $firstLetter = "T"; - } - } else if ($hundredkmN < 10) { - if ($hundredkmE < 5) { - $firstLetter = "N"; - } else { - $firstLetter = "O"; - } - } else { - $firstLetter = "H"; - } - - $secondLetter = ""; - $index = 65 + ((4 - ($hundredkmN % 5)) * 5) + ($hundredkmE % 5); - $ti = $index; - if ($index >= 73) $index++; - $secondLetter = chr($index); - - $e = round(($this->easting - (100000 * $hundredkmE)) / 100); - $n = round(($this->northing - (100000 * $hundredkmN)) / 100); - - return sprintf("%s%s%03d%03d", $firstLetter, $secondLetter, $e, $n); - } - - - /** - * Convert this grid reference into a latitude and longitude - * - * @return - */ - function toLatLng() { - $airy1830 = new RefEll(6377563.396, 6356256.909); - $OSGB_F0 = 0.9996012717; - $N0 = -100050.0; - $E0 = 400110.0; - $phi0 = deg2rad(49.0); - $lambda0 = deg2rad(-2.0); - $a = $airy1830->maj; - $b = $airy1830->min; - $eSquared = $airy1830->ecc; - $phi = 0.0; - $lambda = 0.0; - $E = $this->easting; - $N = $this->northing; - $n = ($a - $b) / ($a + $b); - $M = 0.0; - $phiPrime = (($N - $N0) / ($a * $OSGB_F0)) + $phi0; - do { - $M = - ($b * $OSGB_F0) - * (((1 + $n + ((5.0 / 4.0) * $n * $n) + ((5.0 / 4.0) * $n * $n * $n)) - * ($phiPrime - $phi0)) - - (((3 * $n) + (3 * $n * $n) + ((21.0 / 8.0) * $n * $n * $n)) - * sin($phiPrime - $phi0) - * cos($phiPrime + $phi0)) - + ((((15.0 / 8.0) * $n * $n) + ((15.0 / 8.0) * $n * $n * $n)) - * sin(2.0 * ($phiPrime - $phi0)) - * cos(2.0 * ($phiPrime + $phi0))) - - (((35.0 / 24.0) * $n * $n * $n) - * sin(3.0 * ($phiPrime - $phi0)) - * cos(3.0 * ($phiPrime + $phi0)))); - $phiPrime += ($N - $N0 - $M) / ($a * $OSGB_F0); - } while (($N - $N0 - $M) >= 0.001); - $v = $a * $OSGB_F0 * pow(1.0 - $eSquared * sinSquared($phiPrime), -0.5); - $rho = - $a - * $OSGB_F0 - * (1.0 - $eSquared) - * pow(1.0 - $eSquared * sinSquared($phiPrime), -1.5); - $etaSquared = ($v / $rho) - 1.0; - $VII = tan($phiPrime) / (2 * $rho * $v); - $VIII = - (tan($phiPrime) / (24.0 * $rho * pow($v, 3.0))) - * (5.0 - + (3.0 * tanSquared($phiPrime)) - + $etaSquared - - (9.0 * tanSquared($phiPrime) * $etaSquared)); - $IX = - (tan($phiPrime) / (720.0 * $rho * pow($v, 5.0))) - * (61.0 - + (90.0 * tanSquared($phiPrime)) - + (45.0 * tanSquared($phiPrime) * tanSquared($phiPrime))); - $X = sec($phiPrime) / $v; - $XI = - (sec($phiPrime) / (6.0 * $v * $v * $v)) - * (($v / $rho) + (2 * tanSquared($phiPrime))); - $XII = - (sec($phiPrime) / (120.0 * pow($v, 5.0))) - * (5.0 - + (28.0 * tanSquared($phiPrime)) - + (24.0 * tanSquared($phiPrime) * tanSquared($phiPrime))); - $XIIA = - (sec($phiPrime) / (5040.0 * pow($v, 7.0))) - * (61.0 - + (662.0 * tanSquared($phiPrime)) - + (1320.0 * tanSquared($phiPrime) * tanSquared($phiPrime)) - + (720.0 - * tanSquared($phiPrime) - * tanSquared($phiPrime) - * tanSquared($phiPrime))); - $phi = - $phiPrime - - ($VII * pow($E - $E0, 2.0)) - + ($VIII * pow($E - $E0, 4.0)) - - ($IX * pow($E - $E0, 6.0)); - $lambda = - $lambda0 - + ($X * ($E - $E0)) - - ($XI * pow($E - $E0, 3.0)) - + ($XII * pow($E - $E0, 5.0)) - - ($XIIA * pow($E - $E0, 7.0)); - - return new LatLng(rad2deg($phi), rad2deg($lambda)); - } - } - -/** - * UTMRef - * - * @package kernel - */ - class UTMRef { - - var $easting; - var $northing; - var $latZone; - var $lngZone; - - - /** - * Create a new object representing a UTM reference. - * - * @param easting - * @param northing - * @param latZone - * @param lngZone - */ - function UTMRef($easting, $northing, $latZone, $lngZone) { - $this->easting = $easting; - $this->northing = $northing; - $this->latZone = $latZone; - $this->lngZone = $lngZone; - } - - - /** - * Return a string representation of this UTM reference - * - * @return - */ - function toString() { - return $this->lngZone . $this->latZone . " " . - $this->easting . " " . $this->northing; - } - - - /** - * Convert this UTM reference to a latitude and longitude - * - * @return the converted latitude and longitude - */ - function toLatLng() { - $wgs84 = new RefEll(6378137, 6356752.314); - $UTM_F0 = 0.9996; - $a = $wgs84->maj; - $eSquared = $wgs84->ecc; - $ePrimeSquared = $eSquared / (1.0 - $eSquared); - $e1 = (1 - sqrt(1 - $eSquared)) / (1 + sqrt(1 - $eSquared)); - $x = $this->easting - 500000.0;; - $y = $this->northing; - $zoneNumber = $this->lngZone; - $zoneLetter = $this->latZone; - - $longitudeOrigin = ($zoneNumber - 1.0) * 6.0 - 180.0 + 3.0; - - // Correct y for southern hemisphere - if ((ord($zoneLetter) - ord("N")) < 0) { - $y -= 10000000.0; - } - - $m = $y / $UTM_F0; - $mu = - $m - / ($a - * (1.0 - - $eSquared / 4.0 - - 3.0 * $eSquared * $eSquared / 64.0 - - 5.0 - * pow($eSquared, 3.0) - / 256.0)); - - $phi1Rad = - $mu - + (3.0 * $e1 / 2.0 - 27.0 * pow($e1, 3.0) / 32.0) * sin(2.0 * $mu) - + (21.0 * $e1 * $e1 / 16.0 - 55.0 * pow($e1, 4.0) / 32.0) - * sin(4.0 * $mu) - + (151.0 * pow($e1, 3.0) / 96.0) * sin(6.0 * $mu); - - $n = - $a - / sqrt(1.0 - $eSquared * sin($phi1Rad) * sin($phi1Rad)); - $t = tan($phi1Rad) * tan($phi1Rad); - $c = $ePrimeSquared * cos($phi1Rad) * cos($phi1Rad); - $r = - $a - * (1.0 - $eSquared) - / pow( - 1.0 - $eSquared * sin($phi1Rad) * sin($phi1Rad), - 1.5); - $d = $x / ($n * $UTM_F0); - - $latitude = ( - $phi1Rad - - ($n * tan($phi1Rad) / $r) - * ($d * $d / 2.0 - - (5.0 - + (3.0 * $t) - + (10.0 * $c) - - (4.0 * $c * $c) - - (9.0 * $ePrimeSquared)) - * pow($d, 4.0) - / 24.0 - + (61.0 - + (90.0 * $t) - + (298.0 * $c) - + (45.0 * $t * $t) - - (252.0 * $ePrimeSquared) - - (3.0 * $c * $c)) - * pow($d, 6.0) - / 720.0)) * (180.0 / pi()); - - $longitude = $longitudeOrigin + ( - ($d - - (1.0 + 2.0 * $t + $c) * pow($d, 3.0) / 6.0 - + (5.0 - - (2.0 * $c) - + (28.0 * $t) - - (3.0 * $c * $c) - + (8.0 * $ePrimeSquared) - + (24.0 * $t * $t)) - * pow($d, 5.0) - / 120.0) - / cos($phi1Rad)) * (180.0 / pi()); - - return new LatLng($latitude, $longitude); - } - } - -/** - * RefEll - * - * @package kernel - */ - class RefEll { - - var $maj; - var $min; - var $ecc; - - - /** - * Create a new RefEll object to represent a reference ellipsoid - * - * @param maj the major axis - * @param min the minor axis - */ - function RefEll($maj, $min) { - $this->maj = $maj; - $this->min = $min; - $this->ecc = (($maj * $maj) - ($min * $min)) / ($maj * $maj); - } - } - - - // ================================================== Mathematical Functions - - function sinSquared($x) { - return sin($x) * sin($x); - } - - function cosSquared($x) { - return cos($x) * cos($x); - } - - function tanSquared($x) { - return tan($x) * tan($x); - } - - function sec($x) { - return 1.0 / cos($x); - } - - - /** - * Take a string formatted as a six-figure OS grid reference (e.g. - * "TG514131") and return a reference to an OSRef object that represents - * that grid reference. The first character must be H, N, S, O or T. - * The second character can be any uppercase character from A through Z - * excluding I. - * - * @param ref - * @return - * @since 2.1 - */ - function getOSRefFromSixFigureReference($ref) { - $char1 = substr($ref, 0, 1); - $char2 = substr($ref, 1, 1); - $east = substr($ref, 2, 3) * 100; - $north = substr($ref, 5, 3) * 100; - if ($char1 == 'H') { - $north += 1000000; - } else if ($char1 == 'N') { - $north += 500000; - } else if ($char1 == 'O') { - $north += 500000; - $east += 500000; - } else if ($char1 == 'T') { - $east += 500000; - } - $char2ord = ord($char2); - if ($char2ord > 73) $char2ord--; // Adjust for no I - $nx = (($char2ord - 65) % 5) * 100000; - $ny = (4 - floor(($char2ord - 65) / 5)) * 100000; - return new OSRef($east + $nx, $north + $ny); - } - - - /** - * Work out the UTM latitude zone from the latitude - * - * @param latitude - * @return - */ - function getUTMLatitudeZoneLetter($latitude) { - if ((84 >= $latitude) && ($latitude >= 72)) return "X"; - else if (( 72 > $latitude) && ($latitude >= 64)) return "W"; - else if (( 64 > $latitude) && ($latitude >= 56)) return "V"; - else if (( 56 > $latitude) && ($latitude >= 48)) return "U"; - else if (( 48 > $latitude) && ($latitude >= 40)) return "T"; - else if (( 40 > $latitude) && ($latitude >= 32)) return "S"; - else if (( 32 > $latitude) && ($latitude >= 24)) return "R"; - else if (( 24 > $latitude) && ($latitude >= 16)) return "Q"; - else if (( 16 > $latitude) && ($latitude >= 8)) return "P"; - else if (( 8 > $latitude) && ($latitude >= 0)) return "N"; - else if (( 0 > $latitude) && ($latitude >= -8)) return "M"; - else if (( -8 > $latitude) && ($latitude >= -16)) return "L"; - else if ((-16 > $latitude) && ($latitude >= -24)) return "K"; - else if ((-24 > $latitude) && ($latitude >= -32)) return "J"; - else if ((-32 > $latitude) && ($latitude >= -40)) return "H"; - else if ((-40 > $latitude) && ($latitude >= -48)) return "G"; - else if ((-48 > $latitude) && ($latitude >= -56)) return "F"; - else if ((-56 > $latitude) && ($latitude >= -64)) return "E"; - else if ((-64 > $latitude) && ($latitude >= -72)) return "D"; - else if ((-72 > $latitude) && ($latitude >= -80)) return "C"; - else return 'Z'; - } - -?> |