QuestPort

Play classic Sierra adventure games (King's Quest, Space Quest, Police Quest...) in the browser. From-scratch TypeScript reimplementations of the AGI v2 and SCI0 interpreters.

No game data is included: load your own copy of the game files (or drop the original floppy images) on the page. Tested with Space Quest I (AGI 2.089 and 2.917), Space Quest II (AGI 2.936) and Space Quest III (SCI0 0.000.685).

License note

QuestPort is licensed under GPL-3.0-or-later (see LICENSE). The SCI0 engine (src/sci/) closely follows ScummVM's GPL-licensed SCI engine (algorithms and lookup tables such as picture brush patterns). Sierra's game data is copyrighted and is not part of this project; neither are AI repaints made from it. Not affiliated with Sierra or its current owners; game names are trademarks of their owners.

Run

npm install
npm run dev        # open the printed URL (e.g. http://localhost:5173)

Game files in public/games/sq1/ load automatically. Without them, the page asks you to pick or drop files: either the extracted AGI files (LOGDIR, PICDIR, VIEWDIR, SNDDIR, VOL.*, OBJECT, WORDS.TOK) or the original .ima floppy images, which are read directly.

Other AGI v2 games may work; pass ?version=2440 (hex interpreter version) if their scripts need a newer opcode table. AGI v3 games (compressed resources, combined DIR file) are not supported yet.

Layout

File	What it does
src/resources.ts	Directory + VOL resource loading
src/picture.ts	Vector picture renderer (visual + priority screens)
src/view.ts	Sprite (view/loop/cel) decoder
src/logic.ts	Logic scripts, opcode table, disassembler
src/interpreter.ts	The VM: main cycle, motion, collision, all commands, save/restore
src/words.ts	WORDS.TOK dictionary and text parser
src/sound.ts	3-voice + noise (PCjr/Tandy) sound renderer
src/screen.ts	320x200 compositor, text, message windows
src/main.ts	Browser glue: canvas, keyboard, audio, file loading

SCI0 engine (src/sci/)

File	What it does
resource.ts	RESOURCE.MAP / RESOURCE.00n loading, LZW + Huffman decompression
picture.ts, screen.ts	Vector pictures (visual/priority/control screens, EGA dithering), priority bands
gfx.ts	Views, fonts, ports/windows, painting primitives
vm.ts	Script VM: segments, objects/classes, bytecode, sends, save/restore of the heap
kernel/core.ts	Lists, strings, math, time, misc kernel calls
kernel/windows.ts, text.ts, controls.ts, menu.ts	Windows, text, dialogs, menu bar, status line
kernel/animate.ts, movement.ts, transitions.ts	Pictures, cast animation, collision, movement, transitions
kernel/input.ts, parser.ts	Events and the SCI0 text parser / Said matching
kernel/sound.ts, sound.ts	kDoSound and the SCI0 sound renderer (AdLib FM / PCjr)
kernel/files.ts	Virtual files and save games (localStorage)
engine.ts	Wires everything together and runs the game loop

Tools (Node, for debugging)

npx tsx tools/pics.ts <outdir> [n...]   # render pictures to PNG
npx tsx tools/views.ts <outdir> n...    # render view sprite sheets
npx tsx tools/disasm.ts [n]             # disassemble logic scripts
npx tsx tools/play.ts <outdir> steps... # headless play: w<cycles> t<text> k<key> s<shot>

npx tsx tools/scipics.ts <outdir> [n...]   # render SCI pictures
npx tsx tools/sci-play.ts <outdir> steps... # headless SCI play: w<ms> k<key> t<text> c<x>,<y> s<shot>
npx tsx tools/parsertest.ts                 # SCI parser tests

Saves are stored in the browser's localStorage.

AI Images mode (SCI)

"Space Quest III — AI Images" shows the same game with repainted art:

• Room backgrounds (tools/sci-ai-pics.ts) and sprites (tools/sci-ai-views.ts) are repainted with xAI's image editor (key in .env.local as XAI_API_KEY) and stored in public/games/sq3/ai. Mostly empty pictures use STRICT=1 so empty space stays empty.
• The engine records what drew every screen pixel (room picture, sprite cel, text glyph, other). src/sci/ai-compose.ts takes room pixels from the repainted background and sprite pixels from the repainted sprite sheet, so walking behind things and all game logic are unchanged.
• Text is redrawn with a smooth font (public/fonts/text.ttf, Source Sans 3, OFL) by src/sci/ai-text.ts.
• Anything without a repaint falls back to the original EGA art. To drop a repaint, remove its entry from public/games/sq3/ai/index.json.
• AI=1 tsx tools/sci-play.ts ... also writes the blended 1280x800 frame for each screenshot.

Online version and AI art packs

Live at https://questport.stern.workers.dev (Cloudflare Workers, npm run deploy). Players load their own game files; nothing is uploaded anywhere.

AI art packs are published encrypted (tools/ai-pack.ts <game dir> writes packs/<id>/, which is not in git). The key is derived from the original game files (src/ai-pack.ts), so a pack only opens for someone who loads that exact game release. Available packs: Space Quest II v2.0F (AGI 2.936) and Space Quest III v1.018 (SCI0).