Add a dynamic point to a layer

This is a simple example of how to use PHPMapScript. It is intended to be for begginers (as me). We are going to add a point on the position the user clicked on a map.

On our MapFile, we have blank Point layer called "INLINE", This is the layer where we are going to add our dynamic point. Here you have a sample:

  LAYER
    NAME "INLINE"
    TYPE POINT
    STATUS ON
   CLASS
       NAME "0"
       STYLE
         COLOR 255 0 0 # red
         MAXSIZE 300 # default 50
         SYMBOL 'phone' #In my case was a nice phone image symbol
         SIZE 16
       END #style
   END #class
 END #layer

PHP code

The source filename is query2.php

<?php

//Load the dynamic library.
dl('php_mapscript.so');
//dl('php_mapscript_42.dll'); //For WinDoS Users

//Convert pixels to map units (got from PHPMapscriptSnippet1)
function click2map ($click_x, $click_y) {
    global $map;
    $e= &$map->extent; //for saving writing
    $x_pct = ($click_x / $map->width);
    $y_pct = 1 - ($click_y / $map->height);
    $x_map = $e->minx + ( ($e->maxx - $e->minx) * $x_pct);
    $y_map = $e->miny + ( ($e->maxy - $e->miny) * $y_pct);

    return array($x_map, $y_map);
}

$map= ms_newMapObj('data/test2.map');
//Convert pixels to map units
$map_pt = click2map($_GET['image_x'],$_GET['image_y'],$map->extent);
//Create the point
$pt = ms_newPointObj();
$pt-> setXY($map_pt[0],$map_pt[1]);

//Draw the map and add the point
$img = $map->draw();
$layer = $map->getLayerByName('INLINE');
$pt->draw($map, $layer, $img, 0 ,'yuhuu');
$url = $img->saveWebImage();
?>

< html>< head></ head>< body>

<form method="get" action="query2.php" >
   <input style="border:thin solid black;" type="image" 
          name="image" src="<?php echo $url?>" />
</form>

< pre>
<!-- Debug Lines -->
<?php
echo "GET\n";
print_r($_GET);
echo "Point:\n";
print_r($pt); ?>
?>
< /pre>
< /body>
< /html>

-- Merlos

Go back to: PHPMapScript