PHP geoPHP::detectFormat方法代码示例

/**
 * Convert a raw coverage value to WKT.
 *
 * @param string $coverage The raw coverage.
 * @return string|null The WKT.
 */
function nl_extractWkt($coverage)
{
    $wkt = null;
    // Get coverage format.
    $format = geoPHP::detectFormat($coverage);
    // Convert / reduce to WKT.
    if (in_array($format, array('wkt', 'kml'))) {
        $wkt = geoPHP::load($coverage)->out('wkt');
    }
    return $wkt;
}

/**
 * Return record coverage data from the NeatlineFeatures plugin.
 *
 * @param $record NeatlineRecord The record to get the feature for.
 * @return string|null
 */
function nl_getNeatlineFeaturesWkt($record)
{
    // Halt if Features is not present.
    if (!plugin_is_active('NeatlineFeatures')) {
        return;
    }
    $db = get_db();
    // Get raw coverage.
    $result = $db->fetchOne("SELECT geo FROM `{$db->prefix}neatline_features`\n        WHERE is_map=1 AND item_id=?;", $record->item_id);
    if ($result) {
        // If KML, convert to WKT.
        if (geoPHP::detectFormat($result) == 'kml') {
            $result = nl_kml2wkt(trim($result));
        } else {
            $result = 'GEOMETRYCOLLECTION(' . implode(',', explode('|', $result)) . ')';
        }
    }
    return $result;
}

 static function detectFormat(&$input)
 {
     $mem = fopen('php://memory', 'r+');
     fwrite($mem, $input, 11);
     // Write 11 bytes - we can detect the vast majority of formats in the first 11 bytes
     fseek($mem, 0);
     $bytes = unpack("c*", fread($mem, 11));
     // If bytes is empty, then we were passed empty input
     if (empty($bytes)) {
         return FALSE;
     }
     // First char is a tab, space or carriage-return. trim it and try again
     if ($bytes[1] == 9 || $bytes[1] == 10 || $bytes[1] == 32) {
         return geoPHP::detectFormat(ltrim($input));
     }
     // Detect WKB or EWKB -- first byte is 1 (little endian indicator)
     if ($bytes[1] == 1) {
         // If SRID byte is TRUE (1), it's EWKB
         if ($bytes[5]) {
             return 'ewkb';
         } else {
             return 'wkb';
         }
     }
     // Detect HEX encoded WKB or EWKB (PostGIS format) -- first byte is 48, second byte is 49 (hex '01' => first-byte = 1)
     if ($bytes[1] == 48 && $bytes[2] == 49) {
         // The shortest possible WKB string (LINESTRING EMPTY) is 18 hex-chars (9 encoded bytes) long
         // This differentiates it from a geohash, which is always shorter than 18 characters.
         if (strlen($input) >= 18) {
             //@@TODO: Differentiate between EWKB and WKB -- check hex-char 10 or 11 (SRID bool indicator at encoded byte 5)
             return 'ewkb:1';
         }
     }
     // Detect GeoJSON - first char starts with {
     if ($bytes[1] == 123) {
         return 'json';
     }
     // Detect EWKT - first char is S
     if ($bytes[1] == 83) {
         return 'ewkt';
     }
     // Detect WKT - first char starts with P (80), L (76), M (77), or G (71)
     $wkt_chars = array(80, 76, 77, 71);
     if (in_array($bytes[1], $wkt_chars)) {
         return 'wkt';
     }
     // Detect XML -- first char is <
     if ($bytes[1] == 60) {
         // grab the first 256 characters
         $string = substr($input, 0, 256);
         if (strpos($string, '<kml') !== FALSE) {
             return 'kml';
         }
         if (strpos($string, '<coordinate') !== FALSE) {
             return 'kml';
         }
         if (strpos($string, '<gpx') !== FALSE) {
             return 'gpx';
         }
         if (strpos($string, '<georss') !== FALSE) {
             return 'georss';
         }
         if (strpos($string, '<rss') !== FALSE) {
             return 'georss';
         }
         if (strpos($string, '<feed') !== FALSE) {
             return 'georss';
         }
     }
     // We need an 8 byte string for geohash and unpacked WKB / WKT
     fseek($mem, 0);
     $string = trim(fread($mem, 8));
     // Detect geohash - geohash ONLY contains lowercase chars and numerics
     preg_match('/[a-z0-9]+/', $string, $matches);
     if ($matches[0] == $string) {
         return 'geohash';
     }
     // What do you get when you cross an elephant with a rhino?
     // http://youtu.be/RCBn5J83Poc
     return FALSE;
 }

function test_detection($value, $format, $file)
{
    $detected = geoPHP::detectFormat($value);
    if ($detected != $format) {
        if ($detected) {
            print 'detected as ' . $detected . "\n";
        } else {
            print "format not detected\n";
        }
    }
    // Make sure it loads using auto-detect
    geoPHP::load($value);
}