Initial commit

main.ts

@@ -0,0 +1,114 @@
+import { parseArgs } from "jsr:@std/cli/parse-args";
+import {
+  BlobReader,
+  BlobWriter,
+  ZipReader,
+} from "@zip-js/zip-js";
+
+async function* parseResponseChunked(response: Response) {
+  const lengthHeader = response.headers.get('Content-Length');
+  if (!lengthHeader) {
+    throw Error("Invalid header");
+  }
+  const length = parseInt(lengthHeader);
+  if (!length) {
+    throw Error('Content-Length header not found');
+  }
+  const buffer = new ArrayBuffer(length);
+  const view = new DataView(buffer);
+  const responseBody = response.body;
+  if (!responseBody) {
+    throw Error("Invalid body");
+  }
+  const reader = responseBody.getReader();
+  let offset = 0;
+  let a = 0;
+  let s = 0;
+  for (; ;) {
+    const { done, value } = await reader.read();
+    if (done) {
+      if (offset < length) throw Error('Content-Length mismatch');
+      break;
+    }
+
+    if (!value) {
+      continue;
+    }
+
+    new Uint8Array(buffer, offset, value.length).set(value);
+    offset += value.length;
+    if (offset > length) {
+      throw Error('Content-Length mismatch');
+    }
+    for (; offset - a >= 4 && (s = view.getUint32(a, true), !(offset - a < 4 + s));) {
+      yield buffer.slice(4 + a, 4 + a + s);
+      a += s + 4;
+    }
+  }
+}
+
+function reader(buffer: ArrayBuffer): [Float32Array<ArrayBuffer>, Uint32Array<ArrayBuffer>] {
+  const view = new DataView(buffer);
+  let offset = 0;
+  const n = view.getUint32(offset, true);
+  offset += 4;
+  const i = view.getUint32(offset, true);
+  offset += 4;
+  const o = new Float32Array(buffer.slice(offset, offset + 4 * n));
+  offset += 4 * n;
+  const a = new Uint32Array(buffer.slice(offset, offset + 4 * i));
+  offset += 4 * i;
+  return [o, a];
+}
+
+if (import.meta.main) {
+  const flags = parseArgs(Deno.args, {
+    string: ["map"],
+  });
+
+  const url = new URL("https://assets.thecdn.io/");
+  const mapIds = new Map([
+    ["perimeter", "9fdba452-9beb-41a4-9100-19a6948e3587"],
+    ["outpost", "4a5b068f-2bcc-4c19-ac2c-33f4fadba063"],
+    ["diremarsh", "8a7afd32-1c1e-4e9e-8649-80a1415d08ba"],
+  ]);
+
+  let mapId: string | undefined;
+  if (flags.map && (mapId = mapIds.get(flags.map))) {
+    url.pathname = `${mapId}.chunks`;
+
+    const response = await fetch(url);
+
+    for await (const chunk of parseResponseChunked(response)) {
+      const zipFileReader = new BlobReader(new Blob([chunk]));
+      const zipReader = new ZipReader(zipFileReader);
+      const firstEntry = (await zipReader.getEntries()).shift();
+      if (!firstEntry || firstEntry.directory) {
+        throw new Error("Invalid zip");
+      }
+
+      const dataWriter = new BlobWriter();
+      const data = await firstEntry.getData(dataWriter);
+
+      await zipReader.close();
+
+      const parsedData = reader(await data.arrayBuffer());
+
+      const [positions, indeces] = parsedData;
+
+      for (let i = 0; i < positions.length; i += 3) {
+        const chunk = positions.slice(i, i + 3);
+        const [x, y, z] = chunk;
+        console.log("v", `${x} ${y} ${z}`);
+      }
+
+      for (let i = 0; i < indeces.length; i += 2) {
+        const chunk = indeces.slice(i, i + 2);
+        const [v1, v2] = chunk;
+        console.log("l", `${v1} ${v2}`);
+      }
+    }
+  } else {
+    throw new Error("Unknown map");
+  }
+}