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<?php/*** Author : Julien Moquet** Inspired by Proj4js from Mike Adair madairATdmsolutions.ca* and Richard Greenwood rich@greenwoodma$p->com* License: LGPL as per: http://www.gnu.org/copyleft/lesser.html*//** datum object*/class proj4phpDatum {public $datum_type;public $datum_params;/**** @param type $proj*/public function __construct( $proj ) {$this->datum_type = Proj4php::$common->PJD_WGS84; //default settingif( isset($proj->datumCode) && $proj->datumCode == 'none' ) {$this->datum_type = Proj4php::$common->PJD_NODATUM;}if( isset( $proj->datum_params ) ) {for( $i = 0; $i < sizeof( $proj->datum_params ); $i++ ) {$proj->datum_params[$i] = floatval( $proj->datum_params[$i] );}if( $proj->datum_params[0] != 0 || $proj->datum_params[1] != 0 || $proj->datum_params[2] != 0 ) {$this->datum_type = Proj4php::$common->PJD_3PARAM;}if( sizeof( $proj->datum_params ) > 3 ) {if( $proj->datum_params[3] != 0 || $proj->datum_params[4] != 0 ||$proj->datum_params[5] != 0 || $proj->datum_params[6] != 0 ) {$this->datum_type = Proj4php::$common->PJD_7PARAM;$proj->datum_params[3] *= Proj4php::$common->SEC_TO_RAD;$proj->datum_params[4] *= Proj4php::$common->SEC_TO_RAD;$proj->datum_params[5] *= Proj4php::$common->SEC_TO_RAD;$proj->datum_params[6] = ($proj->datum_params[6] / 1000000.0) + 1.0;}}$this->datum_params = $proj->datum_params;}if( isset( $proj ) ) {$this->a = $proj->a; //datum object also uses these values$this->b = $proj->b;$this->es = $proj->es;$this->ep2 = $proj->ep2;#$this->datum_params = $proj->datum_params;}}/**** @param type $dest* @return boolean Returns TRUE if the two datums match, otherwise FALSE.* @throws type*/public function compare_datums( $dest ) {if( $this->datum_type != $dest->datum_type ) {return false; // false, datums are not equal} else if( $this->a != $dest->a || abs( $this->es - $dest->es ) > 0.000000000050 ) {// the tolerence for es is to ensure that GRS80 and WGS84// are considered identicalreturn false;} else if( $this->datum_type == Proj4php::$common->PJD_3PARAM ) {return ($this->datum_params[0] == $dest->datum_params[0]&& $this->datum_params[1] == $dest->datum_params[1]&& $this->datum_params[2] == $dest->datum_params[2]);} else if( $this->datum_type == Proj4php::$common->PJD_7PARAM ) {return ($this->datum_params[0] == $dest->datum_params[0]&& $this->datum_params[1] == $dest->datum_params[1]&& $this->datum_params[2] == $dest->datum_params[2]&& $this->datum_params[3] == $dest->datum_params[3]&& $this->datum_params[4] == $dest->datum_params[4]&& $this->datum_params[5] == $dest->datum_params[5]&& $this->datum_params[6] == $dest->datum_params[6]);} else if( $this->datum_type == Proj4php::$common->PJD_GRIDSHIFT ||$dest->datum_type == Proj4php::$common->PJD_GRIDSHIFT ) {throw(new Exception( "ERROR: Grid shift transformations are not implemented." ));return false;}return true; // datums are equal}/** The function Convert_Geodetic_To_Geocentric converts geodetic coordinates* (latitude, longitude, and height) to geocentric coordinates (X, Y, Z),* according to the current ellipsoid parameters.** Latitude : Geodetic latitude in radians (input)* Longitude : Geodetic longitude in radians (input)* Height : Geodetic height, in meters (input)* X : Calculated Geocentric X coordinate, in meters (output)* Y : Calculated Geocentric Y coordinate, in meters (output)* Z : Calculated Geocentric Z coordinate, in meters (output)**/public function geodetic_to_geocentric( $p ) {$Longitude = $p->x;$Latitude = $p->y;$Height = isset( $p->z ) ? $p->z : 0; //Z value not always supplied$Error_Code = 0; // GEOCENT_NO_ERROR;/** * Don't blow up if Latitude is just a little out of the value* * range as it may just be a rounding issue. Also removed longitude* * test, it should be wrapped by cos() and sin(). NFW for PROJ.4, Sep/2001.*/if( $Latitude < -Proj4php::$common->HALF_PI && $Latitude > -1.001 * Proj4php::$common->HALF_PI ) {$Latitude = -Proj4php::$common->HALF_PI;} else if( $Latitude > Proj4php::$common->HALF_PI && $Latitude < 1.001 * Proj4php::$common->HALF_PI ) {$Latitude = Proj4php::$common->HALF_PI;} else if( ($Latitude < -Proj4php::$common->HALF_PI) || ($Latitude > Proj4php::$common->HALF_PI) ) {/* Latitude out of range */Proj4php::reportError( 'geocent:lat out of range:' . $Latitude );return null;}if( $Longitude > Proj4php::$common->PI )$Longitude -= (2 * Proj4php::$common->PI);$Sin_Lat = sin( $Latitude ); /* sin(Latitude) */$Cos_Lat = cos( $Latitude ); /* cos(Latitude) */$Sin2_Lat = $Sin_Lat * $Sin_Lat; /* Square of sin(Latitude) */$Rn = $this->a / (sqrt( 1.0e0 - $this->es * $Sin2_Lat )); /* Earth radius at location */$p->x = ($Rn + $Height) * $Cos_Lat * cos( $Longitude );$p->y = ($Rn + $Height) * $Cos_Lat * sin( $Longitude );$p->z = (($Rn * (1 - $this->es)) + $Height) * $Sin_Lat;return $Error_Code;}/**** @param object $p* @return type*/public function geocentric_to_geodetic( $p ) {/* local defintions and variables *//* end-criterium of loop, accuracy of sin(Latitude) */$genau = 1.E-12;$genau2 = ($genau * $genau);$maxiter = 30;$X = $p->x;$Y = $p->y;$Z = $p->z ? $p->z : 0.0; //Z value not always supplied/*$P; // distance between semi-minor axis and location$RR; // distance between center and location$CT; // sin of geocentric latitude$ST; // cos of geocentric latitude$RX;$RK;$RN; // Earth radius at location$CPHI0; // cos of start or old geodetic latitude in iterations$SPHI0; // sin of start or old geodetic latitude in iterations$CPHI; // cos of searched geodetic latitude$SPHI; // sin of searched geodetic latitude$SDPHI; // end-criterium: addition-theorem of sin(Latitude(iter)-Latitude(iter-1))$At_Pole; // indicates location is in polar region$iter; // of continous iteration, max. 30 is always enough (s.a.)$Longitude;$Latitude;$Height;*/$At_Pole = false;$P = sqrt( $X * $X + $Y * $Y );$RR = sqrt( $X * $X + $Y * $Y + $Z * $Z );/* special cases for latitude and longitude */if( $P / $this->a < $genau ) {/* special case, if P=0. (X=0., Y=0.) */$At_Pole = true;$Longitude = 0.0;/* if (X,Y,Z)=(0.,0.,0.) then Height becomes semi-minor axis* of ellipsoid (=center of mass), Latitude becomes PI/2 */if( $RR / $this->a < $genau ) {$Latitude = Proj4php::$common->HALF_PI;$Height = -$this->b;return;}} else {/* ellipsoidal (geodetic) longitude* interval: -PI < Longitude <= +PI */$Longitude = atan2( $Y, $X );}/* --------------------------------------------------------------* Following iterative algorithm was developped by* "Institut für Erdmessung", University of Hannover, July 1988.* Internet: www.ife.uni-hannover.de* Iterative computation of CPHI,SPHI and Height.* Iteration of CPHI and SPHI to 10**-12 radian res$p->* 2*10**-7 arcsec.* --------------------------------------------------------------*/$CT = $Z / $RR;$ST = $P / $RR;$RX = 1.0 / sqrt( 1.0 - $this->es * (2.0 - $this->es) * $ST * $ST );$CPHI0 = $ST * (1.0 - $this->es) * $RX;$SPHI0 = $CT * $RX;$iter = 0;/* loop to find sin(Latitude) res$p-> Latitude* until |sin(Latitude(iter)-Latitude(iter-1))| < genau */do {++$iter;$RN = $this->a / sqrt( 1.0 - $this->es * $SPHI0 * $SPHI0 );/* ellipsoidal (geodetic) height */$Height = $P * $CPHI0 + $Z * $SPHI0 - $RN * (1.0 - $this->es * $SPHI0 * $SPHI0);$RK = $this->es * $RN / ($RN + $Height);$RX = 1.0 / sqrt( 1.0 - $RK * (2.0 - $RK) * $ST * $ST );$CPHI = $ST * (1.0 - $RK) * $RX;$SPHI = $CT * $RX;$SDPHI = $SPHI * $CPHI0 - $CPHI * $SPHI0;$CPHI0 = $CPHI;$SPHI0 = $SPHI;} while( $SDPHI * $SDPHI > $genau2 && $iter < $maxiter );/* ellipsoidal (geodetic) latitude */$Latitude = atan( $SPHI / abs( $CPHI ) );$p->x = $Longitude;$p->y = $Latitude;$p->z = $Height;return $p;}/*** Convert_Geocentric_To_Geodetic* The method used here is derived from 'An Improved Algorithm for* Geocentric to Geodetic Coordinate Conversion', by Ralph Toms, Feb 1996** @param object Point $p* @return object Point $p*/public function geocentric_to_geodetic_noniter( $p ) {/*$Longitude;$Latitude;$Height;$W; // distance from Z axis$W2; // square of distance from Z axis$T0; // initial estimate of vertical component$T1; // corrected estimate of vertical component$S0; // initial estimate of horizontal component$S1; // corrected estimate of horizontal component$Sin_B0; // sin(B0), B0 is estimate of Bowring aux variable$Sin3_B0; // cube of sin(B0)$Cos_B0; // cos(B0)$Sin_p1; // sin(phi1), phi1 is estimated latitude$Cos_p1; // cos(phi1)$Rn; // Earth radius at location$Sum; // numerator of cos(phi1)$At_Pole; // indicates location is in polar region*/$X = floatval( $p->x ); // cast from string to float$Y = floatval( $p->y );$Z = floatval( $p->z ? $p->z : 0 );$At_Pole = false;if( $X <> 0.0 ) {$Longitude = atan2( $Y, $X );} else {if( $Y > 0 ) {$Longitude = Proj4php::$common->HALF_PI;} else if( Y < 0 ) {$Longitude = -Proj4php::$common->HALF_PI;} else {$At_Pole = true;$Longitude = 0.0;if( $Z > 0.0 ) { /* north pole */$Latitude = Proj4php::$common->HALF_PI;} else if( Z < 0.0 ) { /* south pole */$Latitude = -Proj4php::$common->HALF_PI;} else { /* center of earth */$Latitude = Proj4php::$common->HALF_PI;$Height = -$this->b;return;}}}$W2 = $X * $X + $Y * $Y;$W = sqrt( $W2 );$T0 = $Z * Proj4php::$common->AD_C;$S0 = sqrt( $T0 * $T0 + $W2 );$Sin_B0 = $T0 / $S0;$Cos_B0 = $W / $S0;$Sin3_B0 = $Sin_B0 * $Sin_B0 * $Sin_B0;$T1 = $Z + $this->b * $this->ep2 * $Sin3_B0;$Sum = $W - $this->a * $this->es * $Cos_B0 * $Cos_B0 * $Cos_B0;$S1 = sqrt( $T1 * $T1 + $Sum * $Sum );$Sin_p1 = $T1 / $S1;$Cos_p1 = $Sum / $S1;$Rn = $this->a / sqrt( 1.0 - $this->es * $Sin_p1 * $Sin_p1 );if( $Cos_p1 >= Proj4php::$common->COS_67P5 ) {$Height = $W / $Cos_p1 - $Rn;} else if( $Cos_p1 <= -Proj4php::$common->COS_67P5 ) {$Height = $W / -$Cos_p1 - $Rn;} else {$Height = $Z / $Sin_p1 + $Rn * ($this->es - 1.0);}if( $At_Pole == false ) {$Latitude = atan( $Sin_p1 / $Cos_p1 );}$p->x = $Longitude;$p->y = $Latitude;$p->z = $Height;return $p;}/************************************************************** */// pj_geocentic_to_wgs84( p )// p = point to transform in geocentric coordinates (x,y,z)public function geocentric_to_wgs84( $p ) {if( $this->datum_type == Proj4php::$common->PJD_3PARAM ) {// if( x[io] == HUGE_VAL )// continue;$p->x += $this->datum_params[0];$p->y += $this->datum_params[1];$p->z += $this->datum_params[2];} else if( $this->datum_type == Proj4php::$common->PJD_7PARAM ) {$Dx_BF = $this->datum_params[0];$Dy_BF = $this->datum_params[1];$Dz_BF = $this->datum_params[2];$Rx_BF = $this->datum_params[3];$Ry_BF = $this->datum_params[4];$Rz_BF = $this->datum_params[5];$M_BF = $this->datum_params[6];// if( x[io] == HUGE_VAL )// continue;$p->x = $M_BF * ( $p->x - $Rz_BF * $p->y + $Ry_BF * $p->z) + $Dx_BF;$p->y = $M_BF * ( $Rz_BF * $p->x + $p->y - $Rx_BF * $p->z) + $Dy_BF;$p->z = $M_BF * (-$Ry_BF * $p->x + $Rx_BF * $p->y + $p->z) + $Dz_BF;}}/*************************************************************** */// pj_geocentic_from_wgs84()// coordinate system definition,// point to transform in geocentric coordinates (x,y,z)public function geocentric_from_wgs84( $p ) {if( $this->datum_type == Proj4php::$common->PJD_3PARAM ) {//if( x[io] == HUGE_VAL )// continue;$p->x -= $this->datum_params[0];$p->y -= $this->datum_params[1];$p->z -= $this->datum_params[2];} else if( $this->datum_type == Proj4php::$common->PJD_7PARAM ) {$Dx_BF = $this->datum_params[0];$Dy_BF = $this->datum_params[1];$Dz_BF = $this->datum_params[2];$Rx_BF = $this->datum_params[3];$Ry_BF = $this->datum_params[4];$Rz_BF = $this->datum_params[5];$M_BF = $this->datum_params[6];$x_tmp = ($p->x - $Dx_BF) / $M_BF;$y_tmp = ($p->y - $Dy_BF) / $M_BF;$z_tmp = ($p->z - $Dz_BF) / $M_BF;//if( x[io] == HUGE_VAL )// continue;$p->x = $x_tmp + $Rz_BF * $y_tmp - $Ry_BF * $z_tmp;$p->y = -$Rz_BF * $x_tmp + $y_tmp + $Rx_BF * $z_tmp;$p->z = $Ry_BF * $x_tmp - $Rx_BF * $y_tmp + $z_tmp;} //cs_geocentric_from_wgs84()}}