| New file |
|---|
| 0,0 → 1,80 |
|---|
| <?php |
| /** |
| * Author : Julien Moquet |
| * |
| * Inspired by Proj4php from Mike Adair madairATdmsolutions.ca |
| * and Richard Greenwood rich@greenwoodma$p->com |
| * License: LGPL as per: http://www.gnu.org/copyleft/lesser.html |
| */ |
| /******************************************************************************* |
| NAME EQUIRECTANGULAR |
| |
| PURPOSE: Transforms input longitude and latitude to Easting and |
| Northing for the Equirectangular projection. The |
| longitude and latitude must be in radians. The Easting |
| and Northing values will be returned in meters. |
| |
| PROGRAMMER DATE |
| ---------- ---- |
| T. Mittan Mar, 1993 |
| |
| ALGORITHM REFERENCES |
| |
| 1. Snyder, John P., "Map Projections--A Working Manual", U.S. Geological |
| Survey Professional Paper 1395 (Supersedes USGS Bulletin 1532), United |
| State Government Printing Office, Washington D.C., 1987. |
| |
| 2. Snyder, John P. and Voxland, Philip M., "An Album of Map Projections", |
| U.S. Geological Survey Professional Paper 1453 , United State Government |
| Printing Office, Washington D.C., 1989. |
| *******************************************************************************/ |
| class Proj4phpProjEqui { |
| |
| public function init() { |
| if( !$this->x0 ) |
| $this->x0 = 0; |
| if( !$this->y0 ) |
| $this->y0 = 0; |
| if( !$this->lat0 ) |
| $this->lat0 = 0; |
| if( !$this->long0 ) |
| $this->long0 = 0; |
| ///$this->t2; |
| } |
| |
| /* Equirectangular forward equations--mapping lat,long to x,y |
| --------------------------------------------------------- */ |
| public function forward( $p ) { |
| |
| $lon = $p->x; |
| $lat = $p->y; |
| |
| $dlon = Proj4php::$common->adjust_lon( $lon - $this->long0 ); |
| $x = $this->x0 + $this->a * $dlon * cos( $this->lat0 ); |
| $y = $this->y0 + $this->a * $lat; |
| |
| $this->t1 = $x; |
| $this->t2 = cos( $this->lat0 ); |
| $p->x = $x; |
| $p->y = $y; |
| return $p; |
| } |
| |
| /* Equirectangular inverse equations--mapping x,y to lat/long |
| --------------------------------------------------------- */ |
| public function inverse( $p ) { |
| |
| $p->x -= $this->x0; |
| $p->y -= $this->y0; |
| $lat = $p->y / $this->a; |
| |
| if( abs( $lat ) > Proj4php::$common->HALF_PI ) { |
| Proj4php::reportError( "equi:Inv:DataError" ); |
| } |
| $lon = Proj4php::$common->adjust_lon( $this->long0 + $p->x / ($this->a * cos( $this->lat0 )) ); |
| $p->x = $lon; |
| $p->y = $lat; |
| } |
| } |
| |
| Proj4php::$proj['equi'] = new Proj4phpProjEqui(); |