WKT.class.php in geoPHP 7

File

geoPHP/lib/adapters/WKT.class.php

<?php

/**
 * WKT (Well Known Text) Adapter
 */
class WKT extends GeoAdapter {

  /**
   * Read WKT string into geometry objects
   *
   * @param string $WKT A WKT string
   *
   * @return Geometry
   */
  public function read($wkt) {
    $wkt = trim($wkt);

    // If it contains a ';', then it contains additional SRID data
    if (strpos($wkt, ';')) {
      $parts = explode(';', $wkt);
      $wkt = $parts[1];
      $eparts = explode('=', $parts[0]);
      $srid = $eparts[1];
    }
    else {
      $srid = NULL;
    }

    // If geos is installed, then we take a shortcut and let it parse the WKT
    if (geoPHP::geosInstalled()) {
      $reader = new GEOSWKTReader();
      if ($srid) {
        $geom = geoPHP::geosToGeometry($reader
          ->read($wkt));
        $geom
          ->setSRID($srid);
        return $geom;
      }
      else {
        return geoPHP::geosToGeometry($reader
          ->read($wkt));
      }
    }
    $wkt = str_replace(', ', ',', $wkt);

    // For each geometry type, check to see if we have a match at the
    // beginning of the string. If we do, then parse using that type
    foreach (geoPHP::geometryList() as $geom_type) {
      $wkt_geom = strtoupper($geom_type);
      if (strtoupper(substr($wkt, 0, strlen($wkt_geom))) == $wkt_geom) {
        $data_string = $this
          ->getDataString($wkt);
        $method = 'parse' . $geom_type;
        if ($srid) {
          $geom = $this
            ->{$method}($data_string);
          $geom
            ->setSRID($srid);
          return $geom;
        }
        else {
          return $this
            ->{$method}($data_string);
        }
      }
    }
  }
  private function parsePoint($data_string) {
    $data_string = $this
      ->trimParens($data_string);

    // If it's marked as empty, then return an empty point
    if ($data_string == 'EMPTY') {
      return new Point();
    }
    $parts = explode(' ', $data_string);
    return new Point($parts[0], $parts[1]);
  }
  private function parseLineString($data_string) {
    $data_string = $this
      ->trimParens($data_string);

    // If it's marked as empty, then return an empty line
    if ($data_string == 'EMPTY') {
      return new LineString();
    }
    $parts = explode(',', $data_string);
    $points = array();
    foreach ($parts as $part) {
      $points[] = $this
        ->parsePoint($part);
    }
    return new LineString($points);
  }
  private function parsePolygon($data_string) {
    $data_string = $this
      ->trimParens($data_string);

    // If it's marked as empty, then return an empty polygon
    if ($data_string == 'EMPTY') {
      return new Polygon();
    }
    $parts = explode('),(', $data_string);
    $lines = array();
    foreach ($parts as $part) {
      if (!$this
        ->beginsWith($part, '(')) {
        $part = '(' . $part;
      }
      if (!$this
        ->endsWith($part, ')')) {
        $part = $part . ')';
      }
      $lines[] = $this
        ->parseLineString($part);
    }
    return new Polygon($lines);
  }
  private function parseMultiPoint($data_string) {
    $data_string = $this
      ->trimParens($data_string);

    // If it's marked as empty, then return an empty MutiPoint
    if ($data_string == 'EMPTY') {
      return new MultiPoint();
    }
    $parts = explode(',', $data_string);
    $points = array();
    foreach ($parts as $part) {
      $points[] = $this
        ->parsePoint($part);
    }
    return new MultiPoint($points);
  }
  private function parseMultiLineString($data_string) {
    $data_string = $this
      ->trimParens($data_string);

    // If it's marked as empty, then return an empty multi-linestring
    if ($data_string == 'EMPTY') {
      return new MultiLineString();
    }
    $parts = explode('),(', $data_string);
    $lines = array();
    foreach ($parts as $part) {

      // Repair the string if the explode broke it
      if (!$this
        ->beginsWith($part, '(')) {
        $part = '(' . $part;
      }
      if (!$this
        ->endsWith($part, ')')) {
        $part = $part . ')';
      }
      $lines[] = $this
        ->parseLineString($part);
    }
    return new MultiLineString($lines);
  }
  private function parseMultiPolygon($data_string) {
    $data_string = $this
      ->trimParens($data_string);

    // If it's marked as empty, then return an empty multi-polygon
    if ($data_string == 'EMPTY') {
      return new MultiPolygon();
    }
    $parts = explode(')),((', $data_string);
    $polys = array();
    foreach ($parts as $part) {

      // Repair the string if the explode broke it
      if (!$this
        ->beginsWith($part, '((')) {
        $part = '((' . $part;
      }
      if (!$this
        ->endsWith($part, '))')) {
        $part = $part . '))';
      }
      $polys[] = $this
        ->parsePolygon($part);
    }
    return new MultiPolygon($polys);
  }
  private function parseGeometryCollection($data_string) {
    $data_string = $this
      ->trimParens($data_string);

    // If it's marked as empty, then return an empty geom-collection
    if ($data_string == 'EMPTY') {
      return new GeometryCollection();
    }
    $geometries = array();
    $matches = array();
    $str = preg_replace('/,\\s*([A-Za-z])/', '|$1', $data_string);
    $components = explode('|', trim($str));
    foreach ($components as $component) {
      $geometries[] = $this
        ->read($component);
    }
    return new GeometryCollection($geometries);
  }
  protected function getDataString($wkt) {
    $first_paren = strpos($wkt, '(');
    if ($first_paren !== FALSE) {
      return substr($wkt, $first_paren);
    }
    elseif (strstr($wkt, 'EMPTY')) {
      return 'EMPTY';
    }
    else {
      return FALSE;
    }
  }

  /**
   * Trim the parenthesis and spaces
   */
  protected function trimParens($str) {
    $str = trim($str);

    // We want to only strip off one set of parenthesis
    if ($this
      ->beginsWith($str, '(')) {
      return substr($str, 1, -1);
    }
    else {
      return $str;
    }
  }
  protected function beginsWith($str, $char) {
    if (substr($str, 0, strlen($char)) == $char) {
      return TRUE;
    }
    else {
      return FALSE;
    }
  }
  protected function endsWith($str, $char) {
    if (substr($str, 0 - strlen($char)) == $char) {
      return TRUE;
    }
    else {
      return FALSE;
    }
  }

  /**
   * Serialize geometries into a WKT string.
   *
   * @param Geometry $geometry
   *
   * @return string The WKT string representation of the input geometries
   */
  public function write(Geometry $geometry) {

    // If geos is installed, then we take a shortcut and let it write the WKT
    if (geoPHP::geosInstalled()) {
      $writer = new GEOSWKTWriter();
      $writer
        ->setTrim(TRUE);
      return $writer
        ->write($geometry
        ->geos());
    }
    if ($geometry
      ->isEmpty()) {
      return strtoupper($geometry
        ->geometryType()) . ' EMPTY';
    }
    else {
      if ($data = $this
        ->extractData($geometry)) {
        return strtoupper($geometry
          ->geometryType()) . ' (' . $data . ')';
      }
    }
  }

  /**
   * Extract geometry to a WKT string
   *
   * @param Geometry $geometry A Geometry object
   *
   * @return string
   */
  public function extractData($geometry) {
    $parts = array();
    switch ($geometry
      ->geometryType()) {
      case 'Point':
        return $geometry
          ->getX() . ' ' . $geometry
          ->getY();
      case 'LineString':
        foreach ($geometry
          ->getComponents() as $component) {
          $parts[] = $this
            ->extractData($component);
        }
        return implode(', ', $parts);
      case 'Polygon':
      case 'MultiPoint':
      case 'MultiLineString':
      case 'MultiPolygon':
        foreach ($geometry
          ->getComponents() as $component) {
          $parts[] = '(' . $this
            ->extractData($component) . ')';
        }
        return implode(', ', $parts);
      case 'GeometryCollection':
        foreach ($geometry
          ->getComponents() as $component) {
          $parts[] = strtoupper($component
            ->geometryType()) . ' (' . $this
            ->extractData($component) . ')';
        }
        return implode(', ', $parts);
    }
  }

}

Classes

Name	Description
WKT	WKT (Well Known Text) Adapter