public function forward($p)
{
$lon = $p->x;
$lat = $p->y;
/* Forward equations
-----------------*/
$dlon = Proj4php::$common->adjust_lon($lon - $this->long0);
$x;
$y;
if (abs($lat) <= Proj4php::$common->EPSLN) {
$x = $this->x0 + $this->R * $dlon;
$y = $this->y0;
}
$theta = Proj4php::$common . asinz(2.0 * abs($lat / Proj4php::$common->PI));
if (abs($dlon) <= Proj4php::$common->EPSLN || abs(abs($lat) - Proj4php::$common->HALF_PI) <= Proj4php::$common->EPSLN) {
$x = $this->x0;
if ($lat >= 0) {
$y = $this->y0 + Proj4php::$common->PI * $this->R * tan(0.5 * $theta);
} else {
$y = $this->y0 + Proj4php::$common->PI * $this->R * -tan(0.5 * $theta);
}
// return(OK);
}
$al = 0.5 * abs(Proj4php::$common->PI / $dlon - $dlon / Proj4php::$common->PI);
$asq = $al * $al;
$sinth = sin($theta);
$costh = cos($theta);
$g = $costh / ($sinth + $costh - 1.0);
$gsq = $g * $g;
$m = $g * (2.0 / $sinth - 1.0);
$msq = $m * $m;
$con = Proj4php::$common->PI * $this->R * ($al * ($g - $msq) + sqrt($asq * ($g - $sq) * ($g - $msq) - ($msq + $asq) * ($gsq - $msq))) / ($msq + $asq);
if ($dlon < 0) {
$con = -$con;
}
$x = $this->x0 + $con;
$con = abs($con / (Proj4php::$common->PI * $this->R));
if ($lat >= 0) {
$y = $this->y0 + Proj4php::$common->PI * $this->R * sqrt(1.0 - $con * $con - 2.0 * $al * $con);
} else {
$y = $this->y0 - Proj4php::$common->PI * $this->R * sqrt(1.0 - $con * $con - 2.0 * $al * $con);
}
$p->x = $x;
$p->y = $y;
return $p;
}
public function inverse($p)
{
$rh;
/* height above ellipsoid */
$z;
/* angle */
$sinz;
$cosz;
/* sin of z and cos of z */
$temp;
$con;
$lon;
$lat;
/* Inverse equations
-----------------*/
$p->x -= $this->x0;
$p->y -= $this->y0;
$rh = sqrt($p->x * $p->x + $p->y * $p->y);
if ($rh > $this->a + 1.0E-7) {
Proj4php::reportError("orthoInvDataError");
}
$z = Proj4php::$common . asinz($rh / $this->a);
$sinz = sin($z);
$cosz = cos($z);
$lon = $this->long0;
if (abs($rh) <= Proj4php::$common->EPSLN) {
$lat = $this->lat0;
}
$lat = Proj4php::$common . asinz($cosz * $this->sin_p14 + $p->y * $sinz * $this->cos_p14 / $rh);
$con = abs($this->lat0) - Proj4php::$common->HALF_PI;
if (abs(con) <= Proj4php::$common->EPSLN) {
if ($this->lat0 >= 0) {
$lon = Proj4php::$common->adjust_lon($this->long0 + atan2($p->x, -$p->y));
} else {
$lon = Proj4php::$common->adjust_lon($this->long0 - atan2(-$p->x, $p->y));
}
}
$con = $cosz - $this->sin_p14 * sin($lat);
$p->x = $lon;
$p->y = $lat;
return $p;
}
