hobbit-text-game

Hobbit Text Game Spectrum

Melbourne House’s The Hobbit (ZX Spectrum, 1982) running in the browser as a readable text game: a transcript instead of a Spectrum screen, a proper text box that works on a phone, tap-to-play options for the exits and things around you, hints, and the location illustrations from the 1985 Macintosh version, in colour.

Everything is one self-contained file, hobbit.html, with version 1.2 of the tape (the bug-fixed release) built in: open it and play. Another tape image can be loaded from the menu and is then remembered by the browser. Nothing is uploaded anywhere; saved games stay in the browser’s storage and can be exported as files.

Also here: two Oregon Trails, Prince of Persia twice, Monkey Island and Shufflepuck Café

The same treatment for MECC’s The Oregon Trail, each a self-contained page that works on a phone and keeps the journey across reloads:

• oregon-trail-1978/ — the original text game from the 1978 Creative Computing listing (oregon.html), illustrated with the landmark pictures, map and tombstone from the 1985 Apple II version.
• oregon-trail-1985/ — the 1985 Apple II game (oregon85.html), ported program by program from its BASIC, with the hunting and rafting screens rebuilt from its machine code and the disks’ own pictures, sprites and tunes.

And an action game, first emulated and then ported:

• prince-of-persia/ — Brøderbund’s 1989 Apple II Prince of Persia (prince.html), the real program from its three disk sides running on a small Apple IIe emulator written for the page (a 65C02, 128K, the language card, a nibble-level Disk II — and no Apple ROM), with a touch pad and button, automatic disk-side swapping and snapshots.
• prince-of-persia-native/ — the same game re-implemented in JavaScript (pop.html) from Jordan Mechner’s published 6502 source: its sequence tables, collision rules, guard programs, movers and level blueprints as native code, drawn with the same hi-res routines, and checked frame by frame against the emulator above. The pictures, tunes and sound effects are captured from the game running there. It can also draw itself with the 1992 Macintosh version’s art, black-and-white or 256-colour, placed by that version’s own tables and rules (a menu setting).

And a LucasArts adventure on an engine written for the page:

• monkey-island/ — The Secret of Monkey Island (the 1993 Macintosh release) on a SCUMM engine ported to JavaScript from ScummVM: the game’s scripts, rooms, actors, costumes, dialogue, verbs, inventory and the Macintosh music all run natively in the browser, with touch controls and saves. It needs your own copy of the game (the StuffIt archive can be chosen as it is) and keeps it on your device.

And a Macintosh bar game, rebuilt from its machine code:

• shufflepuck-cafe/ — Brøderbund’s 1988 Shufflepuck Café (index.html, or the single file shufflepuck.html): air hockey against the nine regulars of a space-port bar, re-implemented in JavaScript from the 68000 program of the Macintosh release — its copy-protection loader was run under an emulator just long enough to decrypt the code, which was then disassembled and ported: the table, the puck’s physics, each opponent’s reflexes from their own parameter tables, their serves and reactions, the chalk-hand scoreboard, the tournament and the roster — drawn with a small QuickDraw from the game’s own pictures, fonts and sounds. Mouse or touch; a phone’s finger drags the paddle from anywhere on the screen.

How it works

The page contains a small ZX Spectrum 48K emulator (a Z80 core plus just enough of the machine for this one game) that runs the real program from the tape image. Instead of showing the Spectrum screen, it hooks the game’s own routines:

• Text — the game’s print routines are intercepted, so the transcript is the game’s real output, re-flowed and set in a readable typeface.
• Input — the game’s keyboard routine is fed from the page’s text box, so the parser is the original, quirks and all. Compound directions are shortened (southwest → sw) because the parser only reads the first letters of a word.
• Options — the exits, the things present and the verbs each thing answers to are read from the game’s own data structures every turn, so the buttons offer only what is possible right now.
• Hints — Jacob Gunness’s 1990 walkthrough, mapped onto the game’s rooms so the relevant steps are shown for wherever Bilbo is.
• Pictures — the Spectrum’s own drawings (captured from the emulated screen when the game draws them), or the Macintosh illustrations, which appear exactly when the original would draw a picture: the first time a place is visited, and on LOOK.
• Saves — the game is kept in the browser after every turn, so reloading the page carries on where you were; the game’s own SAVE/LOAD go to a tape slot, and snapshots capture the whole machine and the transcript on demand.

The built-in tape is whichever image is in tape/ at build time. Any other copy can be loaded from the menu (.tap, .tzx, or a .zip of one; .z80 and .sna snapshots also work): version 1.2 is the bug-fixed release; the 1982 releases (Melbourne House’s own and Sinclair Research Ltd’s) share the earlier code.

Building

python3 build.py        # inlines the JS, the character set, the hints and the pictures into hobbit.html

File	What it is
index_src.html	the page: markup, styles and the interface script
machine.js	the Spectrum machine, the game hooks and the readers for the game’s data
z80.js	Molly Howell’s Z80 core (MIT), with register accessors added
charset/	the 768-byte Spectrum character set the game prints with
tape/	the tape image built into the page
walkthrough.json	the hints, produced by test/walkthrough.js
locpics/	one picture per location, named <room number> <description>.png
locpics.json	the pictures packed for the page, produced by tools/locpics.py locpics
tools/macpics.py	decodes the pictures from the Macintosh version’s data fork
test/	headless checks: play.js runs commands against a tape, browser.js drives the page in Playwright

To change a picture, edit its PNG in locpics/ (240×128, or an exact multiple such as the 960×512 they are kept at), then run python3 tools/locpics.py locpics and python3 build.py.

The Macintosh pictures

The 1985 Macintosh version stores its 55 illustrations in a format of its own: each is a 240×128 image in 16 “inks”, which the Mac showed as black-and-white dither patterns. tools/macpics.py decodes them (the format was worked out from the program’s 68000 code). The inks turned out to be a painter’s palette used consistently across the set — one ink is always sky, one water, one foliage — so the pictures could be coloured; the ones here were then finished by hand. The Mac numbers its pictures differently from the Spectrum’s rooms, so they were paired with the Spectrum’s locations by comparing them with the Spectrum’s own drawings of the same places.

Credits and rights

• The Hobbit is © Melbourne House / Beam Software (Philip Mitchell, Veronika Megler; graphics Kent Rees). The tape image and the illustrations (derived from the Macintosh release) are theirs.
• The Z80 core is © Molly Howell, MIT licence.
• The Spectrum character set is © Amstrad plc, who permit its distribution for emulation.
• The hints are Jacob Gunness’s walkthrough (1 April 1990).
• The emulator, the game hooks and the page are released under the MIT licence (see LICENSE).

This site is open source. Improve this page.