php and PROJ

[Chad Streck]

My apologies for not checking the archive first.

I got the php_proj.c file compiled into a library and linked it to my 
php program the same way I link php_mapscript.so (dl), but it appears 
that pj_init is not returning an object.  Here is the code I'm using to 
pull the parameters from my map file....

// a function to initialize the php_proj from the map file
function proj_init($mapfile) {

       if(file_exists($mapfile) && $fp = fopen($mapfile, 'r')) {

               while (!feof($fp)) {
                       $line = fgets($fp, 1000);

                       if(preg_match("/projection/", $line)) {
                               $projarray = array();

                               $line = fgets($fp, 1000);
                               while(!preg_match("/end/", $line)) {

                                       $line = preg_replace("/^ *\"/", 
"", $line);
                                       $line = preg_replace("/\".*$/", 
"", $line);
                                       $projarray[] = $line;

                                       $line = fgets($fp, 1000);
                               }

                               /////////////////
                               print_debug($projarray);

                               fclose($fp);

                               $pj = pj_init($projarray);

                               /////////////////
                               print_debug($pj);

                               return $pj;
                       }
               }

               fclose($fp);
       }

       return NULL;
}


print_debug will print out a table of the object whether its an array or 
object.  I get what I'm expecting for the first print_debug, but nothing 
for the second.  Here is what I am getting.....


0
proj=tmerc

1
ellps=GRS80

2
units=ft

3
lon_0=-111.916666667

4
lat_0=31.000000000

5
x_0=213360.000

6
y_0=0.000000

7
k=0.999900

8
no_defs


*Fatal error*: Object expected as argument. in 
*/var/www/html/maps/ace.php* on line *246*


Is there any insight as to what I'm doing wrong?

Thanks,
Chad




Assefa Yewondwossen wrote:

> Hi There,
> 
>  Here is an answer posted earlier on the list:
> 
> 
>  There is a php/proj module available in the mapserver distribution
> (.../mapserver/mapscript/php3/php_proj.c).  This module give access to basic
> Proj4 fonctionalities. So
> in your case you could use the functions to convert the Georeferenced
> coordinated to Lat/Long
> coordinates.
> 
> If you are on a Windows platform, You can download the binary versions at :
> 
>  http://www2.dmsolutions.ca/mapserver/dl/php4.0.4pl1_php_proj_dll.zip
>  http://www2.dmsolutions.ca/mapserver/dl/php4.0.3_php_proj_dll.zip
> 
> Later,
> 
> 
> PS :
> 
> Here is a little bit of docs on how to use it :
> 
>    /*
>  *         PHP PROJ4 Module
>  *
>  *  This is a PHP module that gives acces to basic PROJ4 projection
>  *  functionalities.
>  *
>  * There are four functions available in this module :
>  *
>  * 1) pj_init : create and initializes a projection structures
>  *
>  *    PJ pj_init(array_of_parameters)
>  *
>  *    Example : $projarray[0] = "proj=lcc";
>  *              $projarray[1] = "ellps=GRS80";
>  *              $projarray[2] = "lat_0=49";
>  *              $projarray[3] = "lon_0=-95";
>  *              $projarray[4] = "lat_1=49";
>  *              $projarray[5] = "lat_2=77";
>  *
>  *              $pj = pj_init($projarray);
>  *
>  * 2) pj_fwd : Performs a projection from lat/long coordinates to
>  *             cartesian coordinates.
>  *
>  * retrun_array pj_fwd(double lat, double long, PJ pj)
>  *
>  *   Example :  $lat = 45.25;
>  *              $long = -75.42;
>  *
>  *              $ret = pj_fwd($ingeox, $ingeoy, $pj);
>  *              printf("geo x = %f<br>\n", $ret["u"]);
>  *              printf("geo y = %f<br>\n",$ret["v"]);
>  *
>  * 3) pj_inv : Performs a projection from cartesian coordinates to
>  *             lat/long  coordinates .
>  *
>  * retrun_array pj_fwd(double geox, double geoy, PJ pj)
>  *
>  *   Example :  $ingeox = 1537490.335842;
>  *              $ingeoy = -181633.471555;
>  *
>  *              $ret = pj_inv($ingeox, $ingeoy, $pj);
>  *              printf("lat = %f<br>\n", $ret["u"]);
>  *              printf("lon = %f<br>\n",$ret["v"]);
>  *
>  * 4) pj_free : frees PJ structure
>  *
>  *  void pj_free(PJ pj);
>  *
>  **********************************************************************/
> 
> 
> 
> Chad Streck wrote:
> 
>> Thanks everyone for the help in getting our demo up and running.  Its
>> looking like we may be getting this job, which means that for a point
>> file, I'll have to be dynamically creating lat/long points on the map
>> that is projected in AZ-C.  I plan on placing the points on a blank
>> geographic projected layer which will place the points in the correct
>> position, but I'll need to be able to get the world coordinates of a
>> click on the image in lat/long and not AZ-C.  Is there an easy way to do
>> this with php_mapscript or a way to access the PROJ library directly
>> from PHP other than system/exec?
>> 
>> Thanks,
>> Chad Streck
> 
> 
> --
> ----------------------------------------------------------------
> Assefa Yewondwossen
> Software Analyst
> 
> Email: assefa at dmsolutions.ca
> http://www.dmsolutions.ca/
> 
> Phone: (613) 565-5056
> ----------------------------------------------------------------
> 
> 
> 
>