OpenRCT2 · Gymnasiast · Apr 8, 2025 · Apr 2, 2025 · Apr 2, 2025 · Apr 7, 2025
diff --git a/distribution/changelog.txt b/distribution/changelog.txt
@@ -1,6 +1,7 @@
 0.4.22 (in development)
 ------------------------------------------------------------------------
 - Change: [#23803] Lightning strikes and thunder happen at the same frequency independently of the game speed.
+- Change: [#24135] Compress Emscripten js/wasm files.
 - Fix: [#21919] Non-recolourable cars still show colour picker.
 - Fix: [#23108] Missing pieces on Hypercoaster and Hyper-Twister, even with the ‘all drawable track pieces’ cheat enabled.
 - Fix: [#24013] Failure to load a scenario preview image (minimap) could lead to an uncaught exception error message.

diff --git a/emscripten/static/index.html b/emscripten/static/index.html
@@ -3,7 +3,6 @@
     <head>
         <title>OpenRCT2</title>
         <script src="https://cdn.jsdelivr.net/npm/jszip@3.10.1/dist/jszip.min.js" crossorigin=anonymous></script>
-        <script src="openrct2.js"></script>
         <style>
             * { padding: 0; margin: 0; }
             canvas {

diff --git a/emscripten/static/index.js b/emscripten/static/index.js
@@ -12,12 +12,46 @@
     if (!window.SharedArrayBuffer)
     {
         document.getElementById("loadingWebassembly").innerText = "Error! SharedArrayBuffer is not defined. This page required the CORP and COEP response headers.";
+        return;
     }
     if (!window.WebAssembly)
     {
         document.getElementById("loadingWebassembly").innerText = "Error! This page requires WebAssembly. Please upgrade your browser or enable WebAssembly support.";
+        return;
     }
 
+    let assets;
+    try
+    {
+        let req = await fetch("openrct2.zip");
+        if (!req.ok) {
+            throw new Error("Response is not ok!")
+        }
+        let data = await req.blob();
+        let zip = new JSZip();
+        let contents = await zip.loadAsync(data);
+        assets = {
+            js: URL.createObjectURL(new Blob([await zip.file("openrct2.js").async("uint8array")], {type: 'application/json'})),
+            wasm: URL.createObjectURL(new Blob([await zip.file("openrct2.wasm").async("uint8array")], {type: 'application/wasm'}))
+        }
+    }
+    catch(e)
+    {
+        assets = null;
+        console.warn("Failed to fetch openrct2.zip. Will pull not-compressed files", e);
+    }
+
+    await new Promise(resolve => {
+        const script = document.createElement("script");
+        script.src = assets === null ? "openrct2.js" : assets.js;
+        script.addEventListener("load", resolve);
+        script.addEventListener("error", (e) => {
+            document.getElementById("loadingWebassembly").innerText = "Error loading openrct2.js!";
+            console.error(e);
+        });
+        document.body.appendChild(script);
+    })
+
     window.Module = await window.OPENRCT2_WEB(
         {
             noInitialRun: true,
@@ -37,6 +71,10 @@
             monitorRunDependencies: () => {},
             locateFile: function(fileName)
             {
+                if (assets !== null && fileName === "openrct2.wasm")
+                {
+                    return assets.wasm;
+                }
                 console.log("loading", fileName);
                 return fileName;
             }

diff --git a/scripts/build-emscripten b/scripts/build-emscripten
@@ -34,3 +34,4 @@ mkdir -p www/
 cd www/
 cp -r ../openrct2.* ./
 cp -r ../../emscripten/static/* ./
+zip -r openrct2.zip ../openrct2.*