Subversion Repositories eFlore/Projets.eflore-projets

<?php

/**

 * Author : Julien Moquet

 *

 * Inspired by Proj4js from Mike Adair madairATdmsolutions.ca

 *                      and Richard Greenwood rich@greenwoodmap.com

 * License: LGPL as per: http://www.gnu.org/copyleft/lesser.html

 */

class Proj4phpProj {

    /**

     * Property: readyToUse

     * Flag to indicate if initialization is complete for $this Proj object

     */

    public $readyToUse = false;

    /**

     * Property: title

     * The title to describe the projection

     */

    public $title = null;

    /**

     * Property: projName

     * The projection class for $this projection, e.g. lcc (lambert conformal conic,

     * or merc for mercator).  These are exactly equivalent to their Proj4

     * counterparts.

     */

    public $projName = null;

    /**

     * Property: projection

     * The projection object for $this projection. */

    public $projection = null;

    /**

     * Property: units

     * The units of the projection.  Values include 'm' and 'degrees'

     */

    public $units = null;

    /**

     * Property: datum

     * The datum specified for the projection

     */

    public $datum = null;

    /**

     * Property: x0

     * The x coordinate origin

     */

    public $x0 = 0;

    /**

     * Property: y0

     * The y coordinate origin

     */

    public $y0 = 0;

    /**

     * Property: localCS

     * Flag to indicate if the projection is a local one in which no transforms

     * are required.

     */

    public $localCS = false;

    /**

     *

     * @var type

     */

    protected $wktRE = '/^(\w+)\[(.*)\]$/';

    /**

     * Constructor: initialize

     * Constructor for Proj4php::Proj objects

     *

     * Parameters:

     * $srsCode - a code for map projection definition parameters.  These are usually

     * (but not always) EPSG codes.

     */

    public function __construct( $srsCode ) {

        $this->srsCodeInput = $srsCode;

        //check to see if $this is a WKT string

        if( (strpos( $srsCode, 'GEOGCS' ) !== false) ||

            (strpos( $srsCode, 'GEOCCS' ) !== false) ||

            (strpos( $srsCode, 'PROJCS' ) !== false) ||

            (strpos( $srsCode, 'LOCAL_CS' ) !== false) ) {

            $this->parseWKT( $srsCode );

            $this->deriveConstants();

            $this->loadProjCode( $this->projName );

            return;

        }

        // DGR 2008-08-03 : support urn and url

        if( strpos( $srsCode, 'urn:' ) === 0 ) {

            //urn:ORIGINATOR:def:crs:CODESPACE:VERSION:ID

            $urn = explode( ':', $srsCode );

            if( ($urn[1] == 'ogc' || $urn[1] == 'x-ogc') &&

                ($urn[2] == 'def') &&

                ($urn[3] == 'crs') ) {

                $srsCode = $urn[4] . ':' . $urn[strlen( $urn ) - 1];

            }

        } else if( strpos( $srsCode, 'http://' ) === 0 ) {

            //url#ID

            $url = explode( '#', $srsCode );

            if( preg_match( "/epsg.org/", $url[0] ) ) {

                // http://www.epsg.org/#

                $srsCode = 'EPSG:' . $url[1];

            } else if( preg_match( "/RIG.xml/", $url[0] ) ) {

                //http://librairies.ign.fr/geoportail/resources/RIG.xml#

                //http://interop.ign.fr/registers/ign/RIG.xml#

                $srsCode = 'IGNF:' . $url[1];

            }

        }

        $this->srsCode = strtoupper( $srsCode );

        if( strpos( $this->srsCode, "EPSG" ) === 0 ) {

            $this->srsCode = $this->srsCode;

            $this->srsAuth = 'epsg';

            $this->srsProjNumber = substr( $this->srsCode, 5 );

            // DGR 2007-11-20 : authority IGNF

        } else if( strpos( $this->srsCode, "IGNF" ) === 0 ) {

            $this->srsCode = $this->srsCode;

            $this->srsAuth = 'IGNF';

            $this->srsProjNumber = substr( $this->srsCode, 5 );

            // DGR 2008-06-19 : pseudo-authority CRS for WMS

        } else if( strpos( $this->srsCode, "CRS" ) === 0 ) {

            $this->srsCode = $this->srsCode;

            $this->srsAuth = 'CRS';

            $this->srsProjNumber = substr( $this->srsCode, 4 );

        } else {

            $this->srsAuth = '';

            $this->srsProjNumber = $this->srsCode;

        }

        $this->loadProjDefinition();

    }

    /**

     * Function: loadProjDefinition

     *    Loads the coordinate system initialization string if required.

     *    Note that dynamic loading happens asynchronously so an application must

     *    wait for the readyToUse property is set to true.

     *    To prevent dynamic loading, include the defs through a script tag in

     *    your application.

     *

     */

    public function loadProjDefinition() {

        //check in memory

        if( array_key_exists( $this->srsCode, Proj4php::$defs ) ) {

            $this->defsLoaded();

            return;

        }

        //else check for def on the server

        $filename = dirname( __FILE__ ) . '/defs/' . strtoupper( $this->srsAuth ) . $this->srsProjNumber . '.php';

        try {

            Proj4php::loadScript( $filename );

            $this->defsLoaded(); // succes

        } catch ( Exception $e ) {

            $this->loadFromService(); // fail

        }

    }

    /**

     * Function: loadFromService

     *    Creates the REST URL for loading the definition from a web service and

     *    loads it.

     *

     *

     * DO IT AGAIN. : SHOULD PHP CODE BE GET BY WEBSERVICES ?

     */

    public function loadFromService() {

        //else load from web service

        $url = Proj4php::$defsLookupService . '/' . $this->srsAuth . '/' . $this->srsProjNumber . '/proj4/';

        try {

            Proj4php::$defs[strtoupper($this->srsAuth) . ":" . $this->srsProjNumber] = Proj4php::loadScript( $url );

        } catch ( Exception $e ) {

            $this->defsFailed();

        }

    }

    /**

     * Function: defsLoaded

     * Continues the Proj object initilization once the def file is loaded

     *

     */

    public function defsLoaded() {

        $this->parseDefs();

        $this->loadProjCode( $this->projName );

    }

    /**

     * Function: checkDefsLoaded

     *    $this is the loadCheck method to see if the def object exists

     *

     */

    public function checkDefsLoaded() {

        return isset(Proj4php::$defs[$this->srsCode]) && !empty(Proj4php::$defs[$this->srsCode]);

    }

    /**

     * Function: defsFailed

     *    Report an error in loading the defs file, but continue on using WGS84

     *

     */

    public function defsFailed() {

        Proj4php::reportError( 'failed to load projection definition for: ' . $this->srsCode );

        Proj4php::$defs[$this->srsCode] = Proj4php::$defs['WGS84'];  //set it to something so it can at least continue

        $this->defsLoaded();

    }

    /**

     * Function: loadProjCode

     *    Loads projection class code dynamically if required.

     *     Projection code may be included either through a script tag or in

     *     a built version of proj4php

     *

     * An exception occurs if the projection is not found.

     */

    public function loadProjCode( $projName ) {

        if( array_key_exists( $projName, Proj4php::$proj ) ) {

            $this->initTransforms();

            return;

        }

        //the filename for the projection code

        $filename = dirname( __FILE__ ) . '/projCode/' . $projName . '.php';

        try {

            Proj4php::loadScript( $filename );

            $this->loadProjCodeSuccess( $projName );

        } catch ( Exception $e ) {

            $this->loadProjCodeFailure( $projName );

        }

    }

    /**

     * Function: loadProjCodeSuccess

     *    Loads any proj dependencies or continue on to final initialization.

     *

     */

    public function loadProjCodeSuccess( $projName ) {

        if( isset(Proj4php::$proj[$projName]->dependsOn) && !empty(Proj4php::$proj[$projName]->dependsOn)) {

            $this->loadProjCode( Proj4php::$proj[$projName]->dependsOn );

        } else {

            $this->initTransforms();

        }

    }

    /**

     * Function: defsFailed

     *    Report an error in loading the proj file.  Initialization of the Proj

     *    object has failed and the readyToUse flag will never be set.

     *

     */

    public function loadProjCodeFailure( $projName ) {

        Proj4php::reportError( "failed to find projection file for: " . $projName );

        //TBD initialize with identity transforms so proj will still work?

    }

    /**

     * Function: checkCodeLoaded

     *    $this is the loadCheck method to see if the projection code is loaded

     *

     */

    public function checkCodeLoaded( $projName ) {

        return isset(Proj4php::$proj[$projName]) && !empty(Proj4php::$proj[$projName]);

    }

    /**

     * Function: initTransforms

     *    Finalize the initialization of the Proj object

     *

     */

    public function initTransforms() {

        $this->projection = clone(Proj4php::$proj[$this->projName]);

        Proj4php::extend( $this->projection, $this );

        $this->init();

        // initiate depending class

        if( false !== ($dependsOn = isset($this->projection->dependsOn) && !empty($this->projection->dependsOn) ? $this->projection->dependsOn : false) ) {

            Proj4php::extend( Proj4php::$proj[$dependsOn], $this->projection) &&

            Proj4php::$proj[$dependsOn]->init() &&

            Proj4php::extend( $this->projection, Proj4php::$proj[$dependsOn] );

        }

        $this->readyToUse = true;

    }

    /**

     *

     */

    public function init() {

        $this->projection->init();

    }

    /**

     *

     * @param type $pt

     * @return type

     */

    public function forward( $pt ) {

        return $this->projection->forward( $pt );

    }

    /**

     *

     * @param type $pt

     * @return type

     */

    public function inverse( $pt ) {

        return $this->projection->inverse( $pt );

    }

    /**

     * Function: parseWKT

     * Parses a WKT string to get initialization parameters

     *

     */

    public function parseWKT( $wkt ) {

        if( false === ($match = preg_match( $this->wktRE, $wkt, $wktMatch )) )

            return;

        $wktObject = $wktMatch[1];

        $wktContent = $wktMatch[2];

        $wktTemp = explode( ",", $wktContent );

        $wktName = (strtoupper($wktObject) == "TOWGS84") ? "TOWGS84" : array_shift( $wktTemp );

        $wktName = preg_replace( '/^\"/', "", $wktName );

        $wktName = preg_replace( '/\"$/', "", $wktName );

        /*

          $wktContent = implode(",",$wktTemp);

          $wktArray = explode("],",$wktContent);

          for ($i=0; i<sizeof($wktArray)-1; ++$i) {

          $wktArray[$i] .= "]";

          }

         */

        $wktArray = array();

        $bkCount = 0;

        $obj = "";

        foreach( $wktTemp as $token ) {

            $bkCount = substr_count($token, "[") - substr_count($token, "]");

            // ???

            $obj .= $token;

            if( $bkCount === 0 ) {

                array_push( $wktArray, $obj );

                $obj = "";

            } else {

                $obj .= ",";

            }

        }

        //do something based on the type of the wktObject being parsed

        //add in variations in the spelling as required

        switch( $wktObject ) {

            case 'LOCAL_CS':

                $this->projName = 'identity';

                $this->localCS = true;

                $this->srsCode = $wktName;

                break;

            case 'GEOGCS':

                $this->projName = 'longlat';

                $this->geocsCode = $wktName;

                if( !$this->srsCode )

                    $this->srsCode = $wktName;

                break;

            case 'PROJCS':

                $$this->srsCode = $wktName;

                break;

            case 'GEOCCS':

                break;

            case 'PROJECTION':

                $this->projName = Proj4php::$wktProjections[$wktName];

                break;

            case 'DATUM':

                $this->datumName = $wktName;

                break;

            case 'LOCAL_DATUM':

                $this->datumCode = 'none';

                break;

            case 'SPHEROID':

                $this->ellps = $wktName;

                $this->a = floatval( array_shift( $wktArray ) );

                $this->rf = floatval( array_shift( $wktArray ) );

                break;

            case 'PRIMEM':

                $this->from_greenwich = floatval( array_shift( $wktArray ) ); //to radians?

                break;

            case 'UNIT':

                $this->units = $wktName;

                $this->unitsPerMeter = floatval( array_shift( $wktArray ) );

                break;

            case 'PARAMETER':

                $name = strtolower( $wktName );

                $value = floatval( array_shift( $wktArray ) );

                //there may be many variations on the wktName values, add in case

                //statements as required

                switch( $name ) {

                    case 'false_easting':

                        $this->x0 = $value;

                        break;

                    case 'false_northing':

                        $this->y0 = $value;

                        break;

                    case 'scale_factor':

                        $this->k0 = $value;

                        break;

                    case 'central_meridian':

                        $this->long0 = $value * Proj4php::$common->D2R;

                        break;

                    case 'latitude_of_origin':

                        $this->lat0 = $value * Proj4php::$common->D2R;

                        break;

                    case 'more_here':

                        break;

                    default:

                        break;

                }

                break;

            case 'TOWGS84':

                $this->datum_params = $wktArray;

                break;

            //DGR 2010-11-12: AXIS

            case 'AXIS':

                $name = strtolower( $wktName );

                $value = array_shift( $wktArray );

                switch( $value ) {

                    case 'EAST' : $value = 'e';

                        break;

                    case 'WEST' : $value = 'w';

                        break;

                    case 'NORTH': $value = 'n';

                        break;

                    case 'SOUTH': $value = 's';

                        break;

                    case 'UP' : $value = 'u';

                        break;

                    case 'DOWN' : $value = 'd';

                        break;

                    case 'OTHER':

                    default : $value = ' ';

                        break; //FIXME

                }

                if( !$this->axis ) {

                    $this->axis = "enu";

                }

                switch( $name ) {

                    case 'X': $this->axis = $value . substr( $this->axis, 1, 2 );

                        break;

                    case 'Y': $this->axis = substr( $this->axis, 0, 1 ) . $value . substr( $this->axis, 2, 1 );

                        break;

                    case 'Z': $this->axis = substr( $this->axis, 0, 2 ) . $value;

                        break;

                    default : break;

                }

            case 'MORE_HERE':

                break;

            default:

                break;

        }

        foreach( $wktArray as $wktArrayContent )

            $this->parseWKT( $wktArrayContent );

    }

    /**

     * Function: parseDefs

     * Parses the PROJ.4 initialization string and sets the associated properties.

     *

     */

    public function parseDefs() {

        $this->defData = Proj4php::$defs[$this->srsCode];

        #$paramName;

        #$paramVal;

        if( !$this->defData ) {

            return;

        }

        $paramArray = explode( "+", $this->defData );

        for( $prop = 0; $prop < sizeof( $paramArray ); $prop++ ) {

            if( strlen( $paramArray[$prop] ) == 0 )

                continue;

            $property = explode( "=", $paramArray[$prop] );

            $paramName = strtolower( $property[0] );

            if( sizeof( $property ) >= 2 ) {

                $paramVal = $property[1];

            }

            switch( trim( $paramName ) ) {  // trim out spaces

                case "": break;   // throw away nameless parameter

                case "title": $this->title = $paramVal;

                    break;

                case "proj": $this->projName = trim( $paramVal );

                    break;

                case "units": $this->units = trim( $paramVal );

                    break;

                case "datum": $this->datumCode = trim( $paramVal );

                    break;

                case "nadgrids": $this->nagrids = trim( $paramVal );

                    break;

                case "ellps": $this->ellps = trim( $paramVal );

                    break;

                case "a": $this->a = floatval( $paramVal );

                    break;  // semi-major radius

                case "b": $this->b = floatval( $paramVal );

                    break;  // semi-minor radius

                // DGR 2007-11-20

                case "rf": $this->rf = floatval( paramVal );

                    break; // inverse flattening rf= a/(a-b)

                case "lat_0": $this->lat0 = $paramVal * Proj4php::$common->D2R;

                    break;        // phi0, central latitude

                case "lat_1": $this->lat1 = $paramVal * Proj4php::$common->D2R;

                    break;        //standard parallel 1

                case "lat_2": $this->lat2 = $paramVal * Proj4php::$common->D2R;

                    break;        //standard parallel 2

                case "lat_ts": $this->lat_ts = $paramVal * Proj4php::$common->D2R;

                    break;      // used in merc and eqc

                case "lon_0": $this->long0 = $paramVal * Proj4php::$common->D2R;

                    break;       // lam0, central longitude

                case "alpha": $this->alpha = floatval( $paramVal ) * Proj4php::$common->D2R;

                    break;  //for somerc projection

                case "lonc": $this->longc = paramVal * Proj4php::$common->D2R;

                    break;       //for somerc projection

                case "x_0": $this->x0 = floatval( $paramVal );

                    break;  // false easting

                case "y_0": $this->y0 = floatval( $paramVal );

                    break;  // false northing

                case "k_0": $this->k0 = floatval( $paramVal );

                    break;  // projection scale factor

                case "k": $this->k0 = floatval( $paramVal );

                    break;  // both forms returned

                case "r_a": $this->R_A = true;

                    break;                 // sphere--area of ellipsoid

                case "zone": $this->zone = intval( $paramVal, 10 );

                    break;  // UTM Zone

                case "south": $this->utmSouth = true;

                    break;  // UTM north/south

                case "towgs84": $this->datum_params = explode( ",", $paramVal );

                    break;

                case "to_meter": $this->to_meter = floatval( $paramVal );

                    break; // cartesian scaling

                case "from_greenwich": $this->from_greenwich = $paramVal * Proj4php::$common->D2R;

                    break;

                // DGR 2008-07-09 : if pm is not a well-known prime meridian take

                // the value instead of 0.0, then convert to radians

                case "pm": $paramVal = trim( $paramVal );

                    $this->from_greenwich = Proj4php::$primeMeridian[$paramVal] ? Proj4php::$primeMeridian[$paramVal] : floatval( $paramVal );

                    $this->from_greenwich *= Proj4php::$common->D2R;

                    break;

                // DGR 2010-11-12: axis

                case "axis": $paramVal = trim( $paramVal );

                    $legalAxis = "ewnsud";

                    if( strlen( paramVal ) == 3 &&

                        strpos( $legalAxis, substr( $paramVal, 0, 1 ) ) !== false &&

                        strpos( $legalAxis, substr( $paramVal, 1, 1 ) ) !== false &&

                        strpos( $legalAxis, substr( $paramVal, 2, 1 ) ) !== false ) {

                        $this->axis = $paramVal;

                    } //FIXME: be silent ?

                    break;

                case "no_defs": break;

                default: //alert("Unrecognized parameter: " . paramName);

            } // switch()

        } // for paramArray

        $this->deriveConstants();

    }

    /**

     * Function: deriveConstants

     * Sets several derived constant values and initialization of datum and ellipse parameters.

     *

     */

    public function deriveConstants() {

        if( isset( $this->nagrids ) && $this->nagrids == '@null' )

            $this->datumCode = 'none';

        if( isset( $this->datumCode ) && $this->datumCode != 'none' ) {

            $datumDef = Proj4php::$datum[$this->datumCode];

            if( is_array($datumDef ) ) {

                $this->datum_params = array_key_exists( 'towgs84', $datumDef ) ? explode( ',', $datumDef['towgs84'] ) : null;

                $this->ellps = $datumDef['ellipse'];

                $this->datumName = array_key_exists( 'datumName', $datumDef ) ? $datumDef['datumName'] : $this->datumCode;

            }

        }

        if( !isset( $this->a ) ) {    // do we have an ellipsoid?

            if( !isset( $this->ellps ) || strlen( $this->ellps ) == 0 || !array_key_exists( $this->ellps, Proj4php::$ellipsoid ) )

                $ellipse = Proj4php::$ellipsoid['WGS84'];

            else {

                $ellipse = Proj4php::$ellipsoid[$this->ellps];

            }

            Proj4php::extend( $this, $ellipse );

        }

        if( isset( $this->rf ) && !isset( $this->b ) )

            $this->b = (1.0 - 1.0 / $this->rf) * $this->a;

        if ( (isset($this->rf) && $this->rf === 0) || abs($this->a - $this->b) < Proj4php::$common->EPSLN) {

            $this->sphere = true;

            $this->b = $this->a;

        }

        $this->a2 = $this->a * $this->a;          // used in geocentric

        $this->b2 = $this->b * $this->b;          // used in geocentric

        $this->es = ($this->a2 - $this->b2) / $this->a2;  // e ^ 2

        $this->e = sqrt( $this->es );        // eccentricity

        if( isset( $this->R_A ) ) {

            $this->a *= 1. - $this->es * (Proj4php::$common->SIXTH + $this->es * (Proj4php::$common->RA4 + $this->es * Proj4php::$common->RA6));

            $this->a2 = $this->a * $this->a;

            $this->b2 = $this->b * $this->b;

            $this->es = 0.0;

        }

        $this->ep2 = ($this->a2 - $this->b2) / $this->b2; // used in geocentric

        if( !isset( $this->k0 ) )

            $this->k0 = 1.0;    //default value

        //DGR 2010-11-12: axis

        if( !isset( $this->axis ) ) {

            $this->axis = "enu";

        }

        $this->datum = new Proj4phpDatum( $this );

    }

}