git subrepo pull common

subrepo:
  subdir:   "common"
  merged:   "3e799e5"
upstream:
  origin:   "git@github.com:interactive-game-maps/common.git"
  branch:   "master"
  commit:   "3e799e5"
git-subrepo:
  version:  "0.4.9"
  origin:   "???"
  commit:   "???"

common/.gitrepo

@@ -6,7 +6,7 @@
 [subrepo]
 	remote = git@github.com:interactive-game-maps/common.git
 	branch = master
-	commit = 6803ba27211901a896a5496679f62f3410a1e6be
-	parent = 128fbf2ba44392a7f4d3254c034e6c7537d77ee6
+	commit = 3e799e5362c40a0297b779f71f98e3436c14c569
+	parent = 9b65b6fb469e6302e990c771d818ff56236bddb6
 	method = merge
-	cmdver = 0.4.3
+	cmdver = 0.4.9

common/interactive_map.js

@@ -91,8 +91,12 @@ class InteractiveMap {
             minNativeZoom: 3,
             maxNativeZoom: 5,
             noWrap: true,
-            detectRetina: true
+            detectRetina: true,
+            bounds: this.#getTileLayerBounds(url),
         }
+
+        console.log(defaults.bounds)
+
         let params = { ...defaults, ...args };
         params.maxNativeZoom = L.Browser.retina ? params.maxNativeZoom - 1 : params.maxNativeZoom; // 1 level LOWER for high pixel ratio device.
 
@@ -524,4 +528,50 @@ class InteractiveMap {
 
         return interactive_layer;
     }
+
+    /**
+     * Tries to read an adjacent tilemapresource.xml and calculate the bounds for this tile layer.
+     *
+     * Falls back to 256.
+     *
+     * @param {string} url Location of the tiles
+     */
+    #getTileLayerBounds(url) {
+        if (window.location.protocol !== 'file:') {
+            // This request has to be synchronous because we can't set the tile layer bounds after initialization
+            const request = new XMLHttpRequest();
+            request.open("GET", url.replace("{z}/{x}/{y}.png", "tilemapresource.xml"), false); // `false` makes the request synchronous
+            request.send(null);
+
+            if (request.status === 200) {
+                try {
+                    const parser = new DOMParser();
+                    const xmlDoc = parser.parseFromString(request.responseText, "text/xml");
+                    const boundingBox = xmlDoc.getElementsByTagName("BoundingBox")[0];
+                    const reducedBounds = this.#reduceTileSizeBelow256(Math.abs(boundingBox.getAttribute("miny")), Math.abs(boundingBox.getAttribute("maxx")));
+
+                    return L.latLngBounds(L.latLng(0, 0), L.latLng(-reducedBounds[0], reducedBounds[1]));
+                } catch {
+                    console.log("Failed reading tilemapresource.xml");
+                }
+            }
+        }
+
+        return L.latLngBounds(L.latLng(0, 0), L.latLng(-256, 256)); // gdal2tiles.py never produces tiles larger than 256
+    }
+
+    /**
+     * Takes a two numbers and halfs them simultaneously until both are smaller than 256.
+     * @param {number} size1 Number to minify
+     * @param {number} size2 Number to minify similarly
+     * @returns [number, number]
+     */
+    #reduceTileSizeBelow256(size1, size2) {
+        while (size1 > 256 || size2 > 256) {
+            size1 = Math.floor(size1 / 2);
+            size2 = Math.floor(size2 / 2);
+        }
+
+        return [size1, size2];
+    }
 }