index.html provides an effective template of a Zeta instance which will span the whole browser frame.

Please note that index.html must be edited - by default, it points to "my_game.zip", which should be replaced with the name of your game's ZIP file.

I highly recommend using the Reconstruction of ZZT and the Reconstruction of Super ZZT, which are available at https://zeta.asie.pl/, for bundling with your game worlds.

• A canvas object with a width of or larger than 640x350, specified in options.render.canvas.
  • Integer scaling will be applied automatically based on the canvas width/height - CSS styling only resizes the final texture!
• A presence of all the files herein other than "index.html" in a certain directory.

The entrypoint is "ZetaLoad(options, callback);". The callback is optional, and returns an instance of the emulator.

• render.canvas: the element of the desired canvas.
• path: the (relative or absolute) path to the Zeta engine files.
• files: an array containing file entries to be loaded.

• arg: the argument string provided to ZZT's executable. Ignored if "commands" is present.
• commands: a list containing commands to be executed in order. This will override "arg" and ZZT execution - the final entry on the list is assumed to be ZZT! Allowed types:
  • strings of the form "executable name" (no argument!),
  • arrays of the following form: ["executable name", "argument string"], f.e. [["BQUEST.COM", ""], ["BQZZT.EXE", "BQUEST.ZZT"]].
• storage: define the settings for persistent storage. If not present, save files etc. will be stored in memory, and lost with as little as a page refresh.
  • type: can be "auto" (preferred), "localstorage" or "indexeddb".
  • database: for all of the above, a required database name. If you're hosting multiple games on the same domain, you may want to make this unique.
• engine:
  • charset: the character set (8x14 only!) to initially load, as one of:
    • string - filename of a Zeta-supported format,
    • array - of bytes as would be contained in such a .chr file.
  • palette: the palette, to initially load, as one of:
    • string - filename of a Zeta-supported format,
    • object, with the following fields:
      • min - minimum palette value in the array (f.e. 0),
      • max - maximum palette value in the array (f.e. 255),
      • colors - an array of sixteen colors, either:
        • 3-component arrays of range min - max (inclusive),
        • "#012345" or "#012"-format strings.
  • memory_limit: the memory limit, in kilobytes (64-640)
  • extended_memory_limit: the extended (EMS) memory limit, in kilobytes
• render:
  • type: the engine to use for video rendering; can be "auto" (preferred) or "canvas"
  • blink_cycle_duration: the length of a full blink cycle, in seconds; <= 0 to disable; the default is 0.466
  • charset_override: the location of a PNG image file (16x16 chars) overriding the engine's character set, if present
• audio:
  • type: the engine to use for audio rendering; can be "auto" (preferred), "buffer" or "oscillator" (pre-beta15; deprecated)
  • bufferSize (buffer): the audio buffer size, in samples
  • sampleRate (buffer): the audio sampling rate, in Hz
  • noteDelay: the minimum note delay, in milliseconds; 1 is default
  • volume: the volume of the outputted audio stream (range 0.0 - 1.0); 0.2 by default

File entries are stored in the form of an object containing the following keys:

• type:
  • array: local file to be directly added
  • file: remote file to be directly added
  • zip: remote .ZIP file to be unpacked into the VFS
• url: For remotely-acquired types, denotes the URL leading to the file.
• filename: For single-file types, denotes the target filename.
• data: For the "array" type, a byte array containing the file's data.
• filenameMapper: For ZIPs, this can take the form of either:
  • a function which receives an input filename and returns:
    • a string, containing the output filename,
    • null, if the file should not be loaded.
  • an object, containing key->value mappings of all the files to be loaded,
  • a string, containing the name of the directory that should be loaded.
• filenameFilter: For ZIPs, a function which returns true or false to decide whether or not a file should be loaded.
  • Note that filenameFilter runs after filenameMapper.

• emu.getFile(filename) - Returns a byte array, if a given file exists.
• emu.listFiles() - Returns an array of all filenames stored in the virtual filesystem.
• emu.loadCharset(charset) - argument format as in options.emulator.charset. Returns true upon success.
• emu.loadPalette(palette) - argument format as in options.emulator.palette. Returns true upon success.
• emu.setBlinkCycleDuration(duration) - sets blink cycle duration in seconds. Returns true upon success.
• emu.setVolume(volume) - sets volume in range 0.0 - 1.0. Returns true upon success.