Merge pull request #7 from stephan-strate/tileserver-support

Add tile server support

Author: DantSu

src/OpenStreetMap.php

@@ -15,6 +15,10 @@
  */
 class OpenStreetMap
 {
+    /**
+     * @var TileServer Tile server settings, defaults to OpenStreetMaps tile server
+     */
+    protected $tileServer;
     /**
      * @var MapData Data about the generated map (bounding box, size, OSM tile ids...)
      */
@@ -28,17 +32,18 @@ class OpenStreetMap
      */
     protected $draws = [];
 
-
     /**
      * OpenStreetMap constructor.
      * @param LatLng $centerMap Latitude and longitude of the map center
      * @param int $zoom Zoom
      * @param int $imageWidth Width of the generated map image
      * @param int $imageHeight Height of the generated map image
+     * @param TileServer $tileServer Tile server configuration, defaults to OpenStreetMaps tile server
      */
-    public function __construct(LatLng $centerMap, int $zoom, int $imageWidth, int $imageHeight)
+    public function __construct(LatLng $centerMap, int $zoom, int $imageWidth, int $imageHeight, TileServer $tileServer = null)
     {
         $this->mapData = new MapData($centerMap, $zoom, new XY($imageWidth, $imageHeight));
+        $this->tileServer = is_null($tileServer) ? TileServer::defaultTileServer() : $tileServer;
     }
 
     /**
@@ -90,7 +95,7 @@ protected function getMapImage(): Image
         for ($y = $startY; $y < $imgSize->getY(); $y += 256) {
             $xTile = $this->mapData->getTileTopLeft()->getX();
             for ($x = $startX; $x < $imgSize->getX(); $x += 256) {
-                $i = Image::fromCurl('https://tile.openstreetmap.org/' . $this->mapData->getZoom() . '/' . $xTile . '/' . $yTile . '.png');
+                $i = Image::fromCurl($this->tileServer->getTileUrl($xTile, $yTile, $this->mapData->getZoom()));
                 $image->pasteOn($i, $x, $y);
                 ++$xTile;
             }
@@ -100,15 +105,6 @@ protected function getMapImage(): Image
         return $image;
     }
 
-    /**
-     * Get attribution text
-     * @return string Attribution text
-     */
-    protected function getAttributionText(): string
-    {
-        return '© OpenStreetMap contributors';
-    }
-
     /**
      * Draw OpenStreetMap attribution at the right bottom of the image
      * @param Image $image The image of the map
@@ -119,7 +115,7 @@ protected function drawAttribution(Image $image): Image
         $margin = 5;
         $attribution = function (Image $image, $margin): array {
             return $image->writeTextAndGetBoundingBox(
-                $this->getAttributionText(),
+                $this->tileServer->getAttributionText(),
                 __DIR__ . '/resources/font.ttf',
                 10,
                 '0078A8',

src/TileServer.php

@@ -0,0 +1,87 @@
+<?php
+
+namespace DantSu\OpenStreetMapStaticAPI;
+
+/**
+ * DantSu\OpenStreetMapStaticAPI\TileServer define tile server url and related configuration
+ *
+ * @package DantSu\OpenStreetMapStaticAPI
+ * @author Stephan Strate <hello@stephan.codes>
+ * @access public
+ * @see https://github.com/DantSu/php-osm-static-api Github page of this project
+ */
+class TileServer
+{
+    /**
+     * @var string Tile server url, defaults to OpenStreetMap tile server
+     */
+    private $url;
+
+    /**
+     * @var string Tile server attribution according to license
+     */
+    private $attributionText;
+
+    /**
+     * @var string[] Tile server subdomains
+     */
+    private $subdomains;
+
+    /**
+     * TileServer constructor
+     * @param string $url tile server url with placeholders (`x`, `y`, `z`, `r`, `s`)
+     * @param string $attributionText tile server attribution text
+     * @param string $subdomains tile server subdomains
+     */
+    public function __construct(string $url, string $attributionText, string $subdomains = 'abc')
+    {
+        $this->url = $url;
+        $this->attributionText = $attributionText;
+        $this->subdomains = str_split($subdomains);
+    }
+
+    /**
+     * Get tile url for coordinates and zoom level
+     * @param int $x x coordinate
+     * @param int $y y coordinate
+     * @param int $z zoom level
+     * @return string tile url
+     */
+    public function getTileUrl(int $x, int $y, int $z): string
+    {
+        $patterns = ['r', 's', 'x', 'y', 'z'];
+        $replacements = ['', $this->getSubdomain($x, $y), $x, $y, $z];
+        return preg_replace(array_map(function ($character) { return "/\\$?\{$character}/"; }, $patterns), $replacements, $this->url);
+    }
+
+    /**
+     * Select subdomain of tile server to prevent rate limiting on remote server
+     * @param int $x x coordinate
+     * @param int $y y coordinate
+     * @return string selected subdomain
+     * @see https://github.com/Leaflet/Leaflet/blob/main/src/layer/tile/TileLayer.js#L233 Leaflet implementation
+     */
+    protected function getSubdomain(int $x, int $y): string
+    {
+        $index = abs($x + $y) % sizeof($this->subdomains);
+        return $this->subdomains[$index];
+    }
+
+    /**
+     * Get attribution text
+     * @return string Attribution text
+     */
+    public function getAttributionText(): string
+    {
+        return $this->attributionText;
+    }
+
+    /**
+     * Default tile server. OpenStreetMaps with related attribution text
+     * @return TileServer default tile server
+     */
+    public static function defaultTileServer(): TileServer
+    {
+        return new TileServer('https://tile.openstreetmap.org/{z}/{x}/{y}.png', '© OpenStreetMap contributors');
+    }
+}

src/samples/resources/sample4.png

@@ -0,0 +1,38 @@
+<?php
+require_once '../../vendor/autoload.php';
+
+require_once '../MapData.php';
+require_once '../LatLng.php';
+require_once '../Polygon.php';
+require_once '../Markers.php';
+require_once '../OpenStreetMap.php';
+require_once '../XY.php';
+
+use \DantSu\OpenStreetMapStaticAPI\OpenStreetMap;
+use \DantSu\OpenStreetMapStaticAPI\LatLng;
+use \DantSu\OpenStreetMapStaticAPI\Polygon;
+use \DantSu\OpenStreetMapStaticAPI\Markers;
+use DantSu\OpenStreetMapStaticAPI\TileServer;
+
+\header('Content-type: image/png');
+$tileServer = new TileServer('https://stamen-tiles-{s}.a.ssl.fastly.net/toner-lite/{z}/{x}/{y}{r}.png',
+    'Map tiles by Stamen Design, CC BY 3.0 - © OpenStreetMap contributors');
+(new OpenStreetMap(new LatLng(44.351933, 2.568113), 17, 600, 400, $tileServer))
+    ->addMarkers(
+        (new Markers(__DIR__ . '/resources/marker.png'))
+            ->setAnchor(Markers::ANCHOR_CENTER, Markers::ANCHOR_BOTTOM)
+            ->addMarker(new LatLng(44.351933, 2.568113))
+            ->addMarker(new LatLng(44.351510, 2.570020))
+            ->addMarker(new LatLng(44.351873, 2.566250))
+    )
+    ->addDraw(
+        (new Polygon('FF0000', 2, 'FF0000DD'))
+            ->addPoint(new LatLng(44.351172, 2.571092))
+            ->addPoint(new LatLng(44.352097, 2.570045))
+            ->addPoint(new LatLng(44.352665, 2.568107))
+            ->addPoint(new LatLng(44.352887, 2.566503))
+            ->addPoint(new LatLng(44.352806, 2.565972))
+            ->addPoint(new LatLng(44.351517, 2.565672))
+    )
+    ->getImage()
+    ->displayPNG();