Initial import.

vendor/phayes/geophp/lib/adapters/WKB.class.php

@@ -0,0 +1,250 @@
+<?php
+/*
+ * (c) Patrick Hayes
+ *
+ * This code is open-source and licenced under the Modified BSD License.
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+/**
+ * PHP Geometry/WKB encoder/decoder
+ *
+ */
+class WKB extends GeoAdapter
+{
+
+  private $dimension = 2;
+  private $z = FALSE;
+  private $m = FALSE;
+
+  /**
+   * Read WKB into geometry objects
+   *
+   * @param string $wkb
+   *   Well-known-binary string
+   * @param bool $is_hex_string
+   *   If this is a hexedecimal string that is in need of packing
+   *
+   * @return Geometry
+   */
+  public function read($wkb, $is_hex_string = FALSE) {
+    if ($is_hex_string) {
+      $wkb = pack('H*',$wkb);
+    }
+
+    if (empty($wkb)) {
+      throw new Exception('Cannot read empty WKB geometry. Found ' . gettype($wkb));
+    }
+
+    $mem = fopen('php://memory', 'r+');
+    fwrite($mem, $wkb);
+    fseek($mem, 0);
+
+    $geometry = $this->getGeometry($mem);
+    fclose($mem);
+    return $geometry;
+  }
+
+  function getGeometry(&$mem) {
+    $base_info = unpack("corder/ctype/cz/cm/cs", fread($mem, 5));
+    if ($base_info['order'] !== 1) {
+      throw new Exception('Only NDR (little endian) SKB format is supported at the moment');
+    }
+
+    if ($base_info['z']) {
+      $this->dimension++;
+      $this->z = TRUE;
+    }
+    if ($base_info['m']) {
+      $this->dimension++;
+      $this->m = TRUE;
+    }
+
+    // If there is SRID information, ignore it - use EWKB Adapter to get SRID support
+    if ($base_info['s']) {
+      fread($mem, 4);
+    }
+
+    switch ($base_info['type']) {
+      case 1:
+        return $this->getPoint($mem);
+      case 2:
+        return $this->getLinstring($mem);
+      case 3:
+        return $this->getPolygon($mem);
+      case 4:
+        return $this->getMulti($mem,'point');
+      case 5:
+        return $this->getMulti($mem,'line');
+      case 6:
+        return $this->getMulti($mem,'polygon');
+      case 7:
+        return $this->getMulti($mem,'geometry');
+    }
+  }
+
+  function getPoint(&$mem) {
+    $point_coords = unpack("d*", fread($mem,$this->dimension*8));
+    if (!empty($point_coords)) {
+      return new Point($point_coords[1],$point_coords[2]);
+    }
+    else {
+      return new Point(); // EMPTY point
+    }
+  }
+
+  function getLinstring(&$mem) {
+    // Get the number of points expected in this string out of the first 4 bytes
+    $line_length = unpack('L',fread($mem,4));
+
+    // Return an empty linestring if there is no line-length
+    if (!$line_length[1]) return new LineString();
+
+    // Read the nubmer of points x2 (each point is two coords) into decimal-floats
+    $line_coords = unpack('d*', fread($mem,$line_length[1]*$this->dimension*8));
+
+    // We have our coords, build up the linestring
+    $components = array();
+    $i = 1;
+    $num_coords = count($line_coords);
+    while ($i <= $num_coords) {
+      $components[] = new Point($line_coords[$i],$line_coords[$i+1]);
+      $i += 2;
+    }
+    return new LineString($components);
+  }
+
+  function getPolygon(&$mem) {
+    // Get the number of linestring expected in this poly out of the first 4 bytes
+    $poly_length = unpack('L',fread($mem,4));
+
+    $components = array();
+    $i = 1;
+    while ($i <= $poly_length[1]) {
+      $components[] = $this->getLinstring($mem);
+      $i++;
+    }
+    return new Polygon($components);
+  }
+
+  function getMulti(&$mem, $type) {
+    // Get the number of items expected in this multi out of the first 4 bytes
+    $multi_length = unpack('L',fread($mem,4));
+
+    $components = array();
+    $i = 1;
+    while ($i <= $multi_length[1]) {
+      $components[] = $this->getGeometry($mem);
+      $i++;
+    }
+    switch ($type) {
+      case 'point':
+        return new MultiPoint($components);
+      case 'line':
+        return new MultiLineString($components);
+      case 'polygon':
+        return new MultiPolygon($components);
+      case 'geometry':
+        return new GeometryCollection($components);
+    }
+  }
+
+  /**
+   * Serialize geometries into WKB string.
+   *
+   * @param Geometry $geometry
+   *
+   * @return string The WKB string representation of the input geometries
+   */
+  public function write(Geometry $geometry, $write_as_hex = FALSE) {
+    // We always write into NDR (little endian)
+    $wkb = pack('c',1);
+
+    switch ($geometry->getGeomType()) {
+      case 'Point';
+        $wkb .= pack('L',1);
+        $wkb .= $this->writePoint($geometry);
+        break;
+      case 'LineString';
+        $wkb .= pack('L',2);
+        $wkb .= $this->writeLineString($geometry);
+        break;
+      case 'Polygon';
+        $wkb .= pack('L',3);
+        $wkb .= $this->writePolygon($geometry);
+        break;
+      case 'MultiPoint';
+        $wkb .= pack('L',4);
+        $wkb .= $this->writeMulti($geometry);
+        break;
+      case 'MultiLineString';
+        $wkb .= pack('L',5);
+        $wkb .= $this->writeMulti($geometry);
+        break;
+      case 'MultiPolygon';
+        $wkb .= pack('L',6);
+        $wkb .= $this->writeMulti($geometry);
+        break;
+      case 'GeometryCollection';
+        $wkb .= pack('L',7);
+        $wkb .= $this->writeMulti($geometry);
+        break;
+    }
+
+    if ($write_as_hex) {
+      $unpacked = unpack('H*',$wkb);
+      return $unpacked[1];
+    }
+    else {
+      return $wkb;
+    }
+  }
+
+  function writePoint($point) {
+    // Set the coords
+    if (!$point->isEmpty()) {
+      $wkb = pack('dd',$point->x(), $point->y());
+      return $wkb;
+    } else {
+      return '';
+    }
+  }
+
+  function writeLineString($line) {
+    // Set the number of points in this line
+    $wkb = pack('L',$line->numPoints());
+
+    // Set the coords
+    foreach ($line->getComponents() as $point) {
+      $wkb .= pack('dd',$point->x(), $point->y());
+    }
+
+    return $wkb;
+  }
+
+  function writePolygon($poly) {
+    // Set the number of lines in this poly
+    $wkb = pack('L',$poly->numGeometries());
+
+    // Write the lines
+    foreach ($poly->getComponents() as $line) {
+      $wkb .= $this->writeLineString($line);
+    }
+
+    return $wkb;
+  }
+
+  function writeMulti($geometry) {
+    // Set the number of components
+    $wkb = pack('L',$geometry->numGeometries());
+
+    // Write the components
+    foreach ($geometry->getComponents() as $component) {
+      $wkb .= $this->write($component);
+    }
+
+    return $wkb;
+  }
+
+}