libac

TypeScript library for reading Asheron's Call DAT data structures and related HTTP responses.

• Low-level binary reader (BinaryReader) and DAT models/types.
• Parsers for portal and cell DAT file types: GfxObj, Setup, Texture, Surface, SurfaceTexture, Palette, Region, Scene, CellLandblock, LandblockInfo, EnvCell, Environment, MotionTable, Animation.
• Length-correct animation hooks (AnimationFrame, readAnimationHook, all 27 AnimationHookType payloads), reusable by PhysicsScript (0x33).
• multipart/mixed HTTP response parsing (extractBoundary, parseMultipartMixed).
• Node-only, filesystem-backed DAT access (SeekableFileReader, DatDatabase, DatReader).

Installation

npm install @amoeba/libac

The package is ESM-only and requires Node.js 18 or newer. A SideEffects-free browser-safe (universal) build is included for bundlers.

Which entrypoint?

| Entrypoint | Environment | What it includes | | --- | --- | --- | | @amoeba/libac | Browser / universal | Everything that is safe in any JS runtime: BinaryReader, DatFile/DatFileType, GfxObj, Setup, SpellTable, Texture, MotionTable, Animation, the dat/types models, the unpackables, and the multipart helpers. No Node built-ins, Buffer, or fs. | | @amoeba/libac/node | Node.js | The entire universal API plus the filesystem-backed DAT reading: SeekableFileReader, DatDatabase, DatReader. |

The /node entry re-exports everything from the root entry, so in Node you can import your whole API from @amoeba/libac/node.

Browser DAT file reading is not supported yet — it will require an HTTP-Range-based reader in a future release. In the browser you can still parse in-memory buffers (GfxObj.fromBuffer, Setup.fromBuffer) and the multipart helpers.

Usage

Browser / universal

GfxObj.fromBuffer and Setup.fromBuffer accept either a Uint8Array or an ArrayBuffer. Multipart helpers operate on Uint8Array/ArrayBuffer bytes.

import {
  GfxObj,
  Setup,
  extractBoundary,
  parseMultipartMixed,
} from "@amoeba/libac";

// Parse an in-memory DAT file buffer.
const setup = Setup.fromBuffer(setupBytes);
const gfxObj = GfxObj.fromBuffer(gfxObjBytes);

console.log(setup.parts);      // referenced GfxObj IDs
console.log(gfxObj.surfaces);  // texture references

// Parse a multipart/mixed response body.
const boundary = extractBoundary(contentType);
if (boundary) {
  const parts = parseMultipartMixed(responseBytes, boundary);
  for (const part of parts) {
    console.log(part.fileId, part.filename, part.body);
  }
}

Node.js

Import from the /node subpath to get the universal API plus DAT reading from a file on disk.

import { DatDatabase, GfxObj } from "@amoeba/libac/node";

const db = new DatDatabase("path/to/portal.dat");
db.read(); // reads the header and root directory

// ...use db.reader / db.header / db.rootDir to locate and load file data...

db.close();