@lbalab/hqr

HQR Library

A javascript HQR reader/writer for node.js and web browsers. HQR is a simple file format used by the Little Big Adventure 1 & 2 games for storing data.

A HQR file consists of a header followed by a series of entries which are either compressed or not. It can also contain hidden entries, as a mechanism to store several entries in the same index.

For more information about the content of the various HQR files found in LBA1 and LBA2 game folders, see here.

Install

npm install @lbalab/hqr

Examples

Make sure to backup your game files before using this library to mess with them.

Read the palette data:

const fs = require('fs/promises');
const { HQR } = require('@lbalab/hqr');

(async () => {
  const file = await fs.readFile('LBA2/RESS.HQR');
  const hqr = HQR.fromArrayBuffer(
    file.buffer.slice(file.byteOffset, file.byteOffset + file.byteLength)
  );
  console.log(hqr.entries[0].content); // main game palette as an ArrayBuffer
})();

Swap HQR entries:

const fs = require('fs/promises');
const { HQR } = require('@lbalab/hqr');

/*
 ** Swap regular trees with palm trees in citadel island (with rain):
 ** Entry #0: regular tree
 ** Entry #1: palm tree
 */
(async () => {
  const file = await fs.readFile('LBA2/CITADEL.OBL');
  const hqr = HQR.fromArrayBuffer(
    file.buffer.slice(file.byteOffset, file.byteOffset + file.byteLength)
  );
  const tmp = hqr.entries[0];
  hqr.entries[0] = hqr.entries[4];
  hqr.entries[4] = tmp;
  await fs.writeFile('LBA2/CITADEL.OBL', Buffer.from(hqr.toArrayBuffer()));
})();

Change an HQR entry's content:

const fs = require('fs/promises');
const { HQR } = require('@lbalab/hqr');

(async () => {
  const file = await fs.readFile('LBA2/TEXT.HQR');
  const hqr = HQR.fromArrayBuffer(
    file.buffer.slice(file.byteOffset, file.byteOffset + file.byteLength)
  );
  const textBank = new Uint8Array(hqr.entries[1].content);
  /* The string "Resume Game" is at offset 943.
   ** Let's replace the letters e => é.
   */
  textBank[944] = 130;
  textBank[948] = 130;
  textBank[953] = 130;
  fs.writeFile('LBA2/TEXT.HQR', Buffer.from(hqr.toArrayBuffer()));
})();

Create an HQR file programmatically:

const fs = require('fs/promises');
const { HQR, HQREntry, CompressionType } = require('@lbalab/hqr');

/*
 ** This creates a SIMPLE.HQR file from scratch that contains 3 uncompressed entries:
 ** #0: 512 bytes entry filled with 0s
 ** #1: utf-8 string: "Hello world!"
 ** #2: 32 bit unsigned integer with value 42 (little endian)
 */
(async () => {
  const hqr = new HQR();

  // Entry #0: 512 bytes filled with 0s
  hqr.entries.push(new HQREntry(new ArrayBuffer(512), CompressionType.NONE));

  // Entry #1: utf-8 string: "Hello world!"
  const str = 'Hello world!';
  hqr.entries.push(
    new HQREntry(Buffer.from(str, 'utf-8'), CompressionType.NONE)
  );

  // Entry #2: 32 bit unsigned integer with value 42 (little endian)
  const numView = new DataView(new ArrayBuffer(4));
  numView.setUint32(0, 42, true);
  hqr.entries.push(new HQREntry(numView.buffer, CompressionType.NONE));

  await fs.writeFile('SIMPLE.HQR', Buffer.from(hqr.toArrayBuffer()));
})();

Show hidden entries information:

const fs = require('fs/promises');
const { HQR } = require('@lbalab/hqr');

(async () => {
  if (process.argv.length < 3) {
    console.error('Usage: node count-hidden.js <HQR file>');
    process.exit(1);
  }
  const file = await fs.readFile(process.argv[2]);
  const hqr = HQR.fromArrayBuffer(
    file.buffer.slice(file.byteOffset, file.byteOffset + file.byteLength)
  );
  for (let i = 0; i < hqr.entries.length; i++) {
    const entry = hqr.entries[i];
    if (!entry) continue;

    console.log(`Entry ${i} has ${entry.hiddenEntries.length} hidden entries:`);
    let j = 0;
    for (const hEntry of entry.hiddenEntries) {
      console.log(`  Hidden entry #${j}: ${hEntry.content.byteLength} bytes`);
      j++;
    }
  }
})();

/* Example output:

$> node count-hidden.js LBA2/VOX/EN_000.VOX
Entry 154 has 4 hidden entries:
  Hidden entry #0: 187692 bytes
  Hidden entry #1: 156532 bytes
  Hidden entry #2: 144304 bytes
  Hidden entry #3: 78528 bytes
Entry 205 has 1 hidden entries:
  Hidden entry #0: 139520 bytes
Entry 232 has 1 hidden entries:
  Hidden entry #0: 184860 bytes
Entry 316 has 1 hidden entries:
  Hidden entry #0: 116344 bytes

**/

Contributing

Commit format should follow Angular's commit guidelines.