Add support for compressed URL

package.json

@@ -10,6 +10,7 @@
     "@types/google.maps": "^3.48.3",
     "@vitejs/plugin-vue": "^2.2.4",
     "@vueuse/core": "^8.2.0",
+    "fflate": "^0.7.3",
     "js-base64": "^3.5.2",
     "tailwindcss": "^3.0.23",
     "tatween": "^0.2.0",

src/components/Map.vue

@@ -10,6 +10,7 @@
     import { Base64 } from 'js-base64'
     import { onMounted, ref, watch, computed } from 'vue';
     import { watchDebounced } from '@vueuse/core'
+    import { zlibSync, unzlibSync } from 'fflate';
 
     const DEFAULT_MAP_POSITION = [48.862895, 2.286978, 18]
 
@@ -167,15 +168,21 @@
     }
 
     const loadHash = (hash: string) => {
-        if (hash[0] != 'b') {
+        if (hash[0] != 'b' && hash[0] != 'c') {
             return loadLegacyHash(hash);
         }
 
-        const buf = Base64.toUint8Array(hash.substr(1));
+        const isCompressed = hash[0] == 'c';
+        let buf = Base64.toUint8Array(hash.substr(1));
+
         if (!buf) {
             return;
         }
 
+        if (isCompressed) {
+            buf = unzlibSync(buf)
+        }
+
         const meta = new Float32Array(buf.buffer, 0, 4);
         const data = new Float32Array(buf.buffer, 4*4);
 
@@ -240,7 +247,15 @@
             buf[4+i*2] = arrPoly.value[i].lat();
             buf[4+i*2+1] = arrPoly.value[i].lng();
         }
-        return 'b' + Base64.fromUint8Array(new Uint8Array(buf.buffer), true);
+
+        let outbuf = new Uint8Array(buf.buffer);
+        const isCompressed = outbuf.byteLength >= 150;
+
+        if (isCompressed) {
+            outbuf = zlibSync(outbuf, { level: 9 });
+        }
+
+        return (isCompressed ? 'c' : 'b') + Base64.fromUint8Array(outbuf, true);
     })
 
     watch(() => props.density, () => updatePolygonColor());

yarn.lock

@@ -596,6 +596,11 @@ fastq@^1.6.0:
   dependencies:
     reusify "^1.0.4"
 
+fflate@^0.7.3:
+  version "0.7.3"
+  resolved "https://registry.yarnpkg.com/fflate/-/fflate-0.7.3.tgz#288b034ff0e9c380eaa2feff48c787b8371b7fa5"
+  integrity sha512-0Zz1jOzJWERhyhsimS54VTqOteCNwRtIlh8isdL0AXLo0g7xNTfTL7oWrkmCnPhZGocKIkWHBistBrrpoNH3aw==
+
 fill-range@^7.0.1:
   version "7.0.1"
   resolved "https://registry.yarnpkg.com/fill-range/-/fill-range-7.0.1.tgz#1919a6a7c75fe38b2c7c77e5198535da9acdda40"