PHPMapScriptDynamicLine
Here we have another sample code to illustrate the usage of PHPMapScript. It allows an user to draw a line on the fly. Each time the user clicks on the image it is added that point to a line, then the line is drawn on the map.
Basically, the tasks this script does are:
- Create the map
- Create a line
- Add last point to the line
- Create the shape
- Add the line to the shape
- Add the shape to the layer
- Draw the map
This is the layer "lines" used in the code:
LAYER
GROUP "user"
NAME "lines"
TYPE line
STATUS on
CLASS
NAME "0"
TEMPLATE "ttt_query.html"
STYLE
COLOR 255 0 0 # red
END #style
END #class
END #layer
== PHP code ==
The file is called query3.php
<?php
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; //Tip for saving type time
$x_pct = ($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);
}
// --------------- MAIN -----------------------
$map= ms_newMapObj('data/test2.map');
//Avoid register global=Off (that way it is not neccesary use $_POST[])
import_request_variables("gP", "");
if (isset($image_x) && isset($image_y)){
//Convert pixels to map units
$map_pt = click2map($image_x,$image_y);
//Construct the line
$line = ms_newLineObj();
$line->addXY($map_pt[0],$map_pt[1]);
if (is_array($prev_x)) { //Add points of the hidden input fields
foreach ($prev_x as $i => $x){
$line->addXY($x, $prev_y[$i]);
}
}
//Create the shape object that will be added to the layer
$shp = ms_newShapeObj(MS_SHAPE_LINE);
$shp-> add($line);
$layer = $map->getLayerByName('lines');
$layer->addFeature($shp);
}
//Draw the map
$img = $map->draw();
$url = $img->saveWebImage();
//Now add hidden fields to the form
for($i=0;$i<$line->numpoints;$i++) {
$pt = $line->point($i);
$x = $pt->x;
$y = $pt->y;
$HTML_HIDDEN.="<input type=\"hidden\" name=\"prev_x[$i]\" value=\"$x\"/>";
$HTML_HIDDEN.="<input type=\"hidden\" name=\"prev_y[$i]\" value=\"$y\"/>";
}
?>
< html>< head>< title>Yapig</ title></ head>
<!--remove white spaces of the HTML tags -->
< body>
<form method="post" action="query3.php" >
<input style="border:thin solid black;"type="image" name="image" src="<?php echo $url ?>" />
<?php echo $HTML_HIDDEN ?>
</form>
<a href="query3.php">Clear</a>
</ body>
</ html>
-- Merlos
Go to [wiki:PHPMapScript]
