Daventry.Player 0.2.0-alpha

Daventry

Daventry is a C# implementation of Sierra On-Line's adventure game interpreters: AGI, SCI, and ADL, the engine of the Apple II Hi-Res Adventures. It is a port of the engines/agi, engines/sci and engines/adl code from ScummVM, restructured as a set of .NET libraries with a small host contract so the same engines run on the desktop (SDL) and in the browser (Blazor WebAssembly).

Daventry is not a ScummVM fork and does not aim to run anything other than Sierra's own games.

Screenshots

Taken by the headless host from the games' own data, at their native resolutions (Police Quest 4's 320×200 taken with --aspect, stretched to 4:3 as a monitor showed it, to sit beside its 640×480 neighbours).

<table> <tr><th colspan="3">AGI</th></tr> <tr> <td align="center" valign="top"><img src="https://raw.githubusercontent.com/jeffnyman/daventry/main/assets/screenshots/agi-kq2.png" width="280" alt="King's Quest II"><br>King's Quest II</td> <td align="center" valign="top"><img src="https://raw.githubusercontent.com/jeffnyman/daventry/main/assets/screenshots/agi-sq2.png" width="280" alt="Space Quest II"><br>Space Quest II</td> <td align="center" valign="top"><img src="https://raw.githubusercontent.com/jeffnyman/daventry/main/assets/screenshots/agi-goldrush.png" width="280" alt="Gold Rush!"><br>Gold Rush!</td> </tr> <tr><th colspan="3">SCI0 to SCI1.1</th></tr> <tr> <td align="center" valign="top"><img src="https://raw.githubusercontent.com/jeffnyman/daventry/main/assets/screenshots/sci1-sq3.png" width="280" alt="Space Quest III"><br>Space Quest III</td> <td align="center" valign="top"><img src="https://raw.githubusercontent.com/jeffnyman/daventry/main/assets/screenshots/sci1-kq6.png" width="280" alt="King's Quest VI"><br>King's Quest VI</td> <td align="center" valign="top"><img src="https://raw.githubusercontent.com/jeffnyman/daventry/main/assets/screenshots/sci1-lb2.png" width="280" alt="Laura Bow 2: The Dagger of Amon Ra"><br>Laura Bow 2: The Dagger of Amon Ra</td> </tr> <tr><th colspan="3">SCI2 and SCI2.1</th></tr> <tr> <td align="center" valign="top"><img src="https://raw.githubusercontent.com/jeffnyman/daventry/main/assets/screenshots/sci2-kq7.png" width="280" alt="King's Quest VII"><br>King's Quest VII</td> <td align="center" valign="top"><img src="https://raw.githubusercontent.com/jeffnyman/daventry/main/assets/screenshots/sci2-sq6.png" width="280" alt="Space Quest 6"><br>Space Quest 6</td> <td align="center" valign="top"><img src="https://raw.githubusercontent.com/jeffnyman/daventry/main/assets/screenshots/sci2-pq4.png" width="280" alt="Police Quest 4"><br>Police Quest 4</td> </tr> <tr><th colspan="3">SCI3</th></tr> <tr> <td align="center" valign="top"><img src="https://raw.githubusercontent.com/jeffnyman/daventry/main/assets/screenshots/sci3-lsl7.png" width="280" alt="Leisure Suit Larry 7"><br>Leisure Suit Larry 7</td> <td align="center" valign="top"><img src="https://raw.githubusercontent.com/jeffnyman/daventry/main/assets/screenshots/sci3-lighthouse.png" width="280" alt="Lighthouse"><br>Lighthouse</td> <td align="center" valign="top"><img src="https://raw.githubusercontent.com/jeffnyman/daventry/main/assets/screenshots/sci3-rama.png" width="280" alt="RAMA"><br>RAMA</td> </tr> <tr><th colspan="3">ADL</th></tr> <tr> <td align="center" valign="top"><img src="https://raw.githubusercontent.com/jeffnyman/daventry/main/assets/screenshots/adl-mystery-house.png" width="280" alt="Mystery House"><br>Mystery House</td> <td align="center" valign="top"><img src="https://raw.githubusercontent.com/jeffnyman/daventry/main/assets/screenshots/adl-wizard.png" width="280" alt="Wizard and the Princess"><br>Wizard and the Princess</td> <td align="center" valign="top"><img src="https://raw.githubusercontent.com/jeffnyman/daventry/main/assets/screenshots/adl-dark-crystal.png" width="280" alt="The Dark Crystal"><br>The Dark Crystal</td> </tr> </table>

Status

All of ScummVM's engine generations for Sierra's own games, from the Hi-Res Adventures through AGI to SCI3, run from the games' own scripts and data. Most of the checking so far is headless: scripted runs through each game's opening, plus targeted tests. Play testing in the window is the next step. ROADMAP.md has the details, what is deferred and what comes next.

What is ported

AGI and preAGI

• Engine: resources, pictures, views, sprites, the logic interpreter, text, the parser and PCjr/Tandy sound; every Sierra AGI title plays from its first room.
• Detection: ScummVM's MD5 table, with a file-name and WinAGI project-file fallback for fan games.
• Menus and saves: menus, the inventory screen, saving and restoring. Saved games use ScummVM's file layout and have been exchanged with a real ScummVM build in both directions; its compressed files load too.
• preAGI: Mickey's Space Adventure, Winnie the Pooh (DOS) and Troll's Tale have engines of their own over the shared picture, text and speaker code, with their menus, sounds and saved games. Winnie also loads the save file of the original interpreter. Troll's Tale plays from its PC booter disk image, which ScummVM names troll.img; the DOS release's game.dat is the same image and plays too, though ScummVM refuses it under that name.
• Not ported: booter disk images (.img, .ima) and Apple II disk images are recognised by the directory inside them, as ScummVM does, and refused: the 1984-85 King's Quest uses Game Adaptation Language, the interpreter before AGI, which ScummVM does not run either, and the AGI v1 and Apple II loaders are not ported. Nor are the Apple II, IIgs and CoCo3 sound formats.

SCI0 to SCI1.1

• Resources: the maps, volumes and patch files of SCI0 through SCI3, every compression (LZW, Huffman, LZW with view and picture unpacking, DCL, STACpack), and the interpreter generation and game object, detected for all 40 SCI games in the test library. Games are identified by ScummVM's MD5 table with its game-object fallback.
• Graphics: the visual, priority and control screens, EGA dithering and undithering, the system palette with merging and pal-vary, ports and priority bands, vector and SCI1.1 pictures, views with scaling, and bitmap fonts. Every picture, cel and font of every SCI16 game in the library decodes; daventry <game> --picture N --view N browses them.
• Interpreter: the segment manager, scripts, objects, the p-machine, kernel dispatch with ScummVM's signatures, lists, maths, strings, movement, events, windows, animation with transitions, text, controls, the menu bar and status line, the text parser (vocabulary, suffixes, the GNF grammar and Said matching), the SCI1.1 message resources, and the software mouse cursor.
• Fixes for the original scripts: ScummVM's workaround tables and all 911 of its script patches, generated from script_patches.cpp.
• Pathfinding: kAvoidPath, kMergePoly and kIntersections, so clicking on the ground walks the character around obstacles; daventry <game> --click T:x,y does it headless.
• Music: sound resources and Sierra's extended MIDI parser (signals, cues, loop points, hold markers, channel remapping) under the music engine's play list with fades and pausing, on five devices:
  • AdLib, the default: the game's own patch bank on a port of the DOSBox OPL2 emulator (dual OPL2 for stereo).
  • PCjr/Tandy three-voice and the PC speaker.
  • General MIDI through a SoundFont you supply (the MeltySynth synthesiser). Games with a General MIDI patch, such as King's Quest VI, play their GM tracks; games written for the MT-32 alone are mapped with ScummVM's tables (approximate for SCI1 games, as ScummVM warns). Mixed-Up Mother Goose Deluxe has only General MIDI music, so it always takes the SoundFont. Any General MIDI SoundFont works, such as the small Roland_SC-55.sf2 in ScummVM's source (dists/soundfonts, GPL) or GeneralUser GS.
  • Roland MT-32 and CM-32L, the modules Sierra composed for from King's Quest IV to VI, emulated by a C# port of Munt (the emulator inside ScummVM) from ROM dumps you supply. Each game uploads its instruments and shows its messages on the emulated LCD. The output matches Munt sample for sample (tools/Mt32Reference). ROMs are recognised by their contents whatever the files are called, including chip-at-a-time dumps; the CM-32L is preferred, as in ScummVM.
• Sound effects and speech: a sound resource's digital sample plays in preference to the synthesized version, as on a Sound Blaster (--no-digital-sfx keeps the AdLib version). kDoAudio and kDoSync play and lip-sync the speech of the CD games (SOL, WAVE and raw audio, SCI1 audio language maps). Music and cues are clocked from the audio output, or from engine time when nothing reads the audio, so cue-driven scenes advance headless too.
• Saved games: through the games' own dialogs, in ScummVM's format version 46 (the segment manager, the sound play list, the palette, the windows, a thumbnail). Saves have been exchanged with a real ScummVM build in both directions, SCI0 through SCI2.1; --save T:N and --restore T:N do it headless and tools/ScummVmRoundTrip describes the procedure.
• Files the games write (kFileIO) go next to the saves as <game id>-<name>, as ScummVM names them: LSL3's larry3.drv, LSL7's preferences, the Quest for Glory character exports, Phantasmagoria's own save files. Files are read from there first, then from the game folder.
• Determinism: headless runs give the same frames on the same ticks for the same game, input and --seed, whatever the machine is doing, so a scripted run reproduces a report exactly.
• Not ported: CD audio tracks, the Roland D-110, the Amiga and Mac sound drivers, and the Windows-only touches of the SCI1.1 releases (King's Quest VI's high-resolution cels, the alternate General MIDI soundtracks); those releases run as their DOS versions.

SCI2 and SCI2.1

• VM: the SCI32 kernel tables and the 32-bit VM differences: opcode widths, the SCI32 comparison rules, the view-visible flag, the array and bitmap segments.
• Graphics: the plane and screen-item renderer (GfxFrameout): cels of every kind with scaling and remapping, the 256-colour palette with vary, cycling, fades and gamma, the colour remapper, the software cursor, the text renderer with its control codes, the show-style transitions (fades, wipes, irises, pixel dissolves, the palette morph) and picture scrolls.
• Audio: the digital audio mixer (Audio32): speech and sound effects in SOL, WAVE and raw formats, several channels with fades, panning and attenuated mixing.
• Controls: text fields, scroll windows, the message box, kAddLine and hot rectangles.
• Saved games: the SCI32 state in ScummVM's format version 46.
• Not ported: ScummVM's dialog for kMessageBox (boxes are answered with their default button) and the KQ7 video upscaling option.

SCI3

• Scripts: the SCI3 format: no heap, 32-bit header offsets, dword-aligned locals, objects and strings, scripts up to 256 KB resolved through their relocation tables (VM registers carry 18-bit offsets, saved in ScummVM's packed form).
• Objects: selectors described in a bank of 32-selector groups, properties found by selector, the info and superP opcodes, and the SCI3 redraw pass of the plane renderer.
• Discs: audio kept per CD, and the subfolders ScummVM searches for a game's files (movies, robots, patches and the others).
• Checked: Leisure Suit Larry 7 runs its logo, opening and first scene the same way as ScummVM 2026.4.0. Lighthouse plays its logo and intro into the first room. RAMA plays its opening into the hangar, and saves, restores and deletes through its own screens. Phantasmagoria 2 (the US release) plays its title video and opening into Curtis's bedroom, and saves and restores there.

SCI32 video

• Robot (*.RBT): King's Quest VII's cut scenes and the inserts of the later games, with their audio channel.
• VMD, Coktel's format (Phantasmagoria, Lighthouse, RAMA): 8-bit frames with their palettes and DPCM sound. SCI3 shows them through the renderer as a screen item; SCI2.1 draws them straight into the game buffer.
• Duck (Phantasmagoria 2): AVI files with TrueMotion 1 video and Duck DK3 ADPCM sound. The frames are 16-bit colour, so while one plays the engine hands the host true-colour frames: the game's screen converted from its palette, with the video drawn over it. A click or Escape ends a video, as in ScummVM.
• Not ported: the AVI and SEQ players (King's Quest VII for Windows, some SCI2 movies), QuickTime (Macintosh releases), and VMDs packed with Indeo 3 or in 16 and 24 bits.

ADL

• Games: the seven Hi-Res Adventures (1980 to 1982) run from their Apple II disk images: all four ADL engine generations, the picture drawing of each (Mystery House's line art, the pattern fills of the later games), Mystery House's DOS 3.3 files, Ulysses' four releases including Green Valley's animated title and the Atari 8-bit one, Time Zone's 41 regions on twelve disk sides, and The Dark Crystal's singular and plural text.
• Disk images: Daventry.Core.Formats decodes .dsk, .do, .d13, .nib and .woz images of 13- and 16-sector disks and reads Apple DOS 3.3 catalogs. Games are identified by ScummVM's checksums of the disks' contents, so a dump keeps whatever name it came with.
• Display: ScummVM's default NTSC TV emulation, the colours of the composite signal, in true colour, with the text sharp and white; Mystery House defaults to its monochrome picture. --no-ntsc switches to the RGB-monitor colours or a green monochrome monitor. The speaker plays the games' tones and bells.
• Saved games: ScummVM's ADL format, exchanged with a ScummVM build in both directions.
• Not ported: the text-to-speech option, and the debugger console and its scripted input.

Browser host

• Daventry.Host.Browser is a Blazor component and Daventry.Web a page around it. The frames go to a canvas, the sound through Web Audio, the keyboard and mouse come from the canvas, saved games live in the browser's local storage, and the page's animation frames are the clock.
• You pick a game folder in the page and nothing leaves the browser; a site can also host games of its own and load them from a manifest. Subfolders are read with their paths, so a game whose data sits a folder or two down (King's Quest 7, Space Quest 6, Codename: Iceman) is found.
• Picked games can be kept in the browser (IndexedDB) and played again from a "Your games" list. Saved games can be downloaded, imported and deleted in the page, so they move between the browser, the desktop player and ScummVM.
• Checked with headless Chrome (tools/BrowserSmoke): King's Quest I in both versions plays with keys, typing and the mouse, saves and restores through its own dialogs, and runs at 60 ticks a second at well under a millisecond a tick without ahead-of-time compilation.

Building and playing

Requires the .NET 10 SDK.

dotnet build
dotnet test
dotnet run --project src/Daventry.Player -- <path-to-game-folder>

The game folder can hold the game itself or have it a folder or two down. The player also installs as a dotnet tool, daventry (dotnet tool install -g Daventry.Player --prerelease).

Player options

daventry --help lists the rest: headless screenshots and WAV captures, scripted keys, typing, clicks, saves and restores, the random seed, and the picture and view browser.

Saved games

Saves go to Daventry/saves in the user's application data, one folder for all the games as in ScummVM: every file name starts with the game id, and the Quest for Glory games find the heroes the earlier ones exported. --saves DIR keeps them anywhere else. The per-game folders of earlier versions (Daventry/saves/<game id>) are moved into it on the next start. Daventry names SCI saves <game id>.NNN where ScummVM uses its target name, so a save moved to ScummVM may need renaming.

Games on several CDs

Daventry reads a game from one folder, so a game on several CDs is copied into one, as ScummVM asks. These have been set up and checked; when a disc carries no RESOURCE.AUD, ScummVM keeps the sound per disc, and so does Daventry.

In the browser

dotnet run --project src/Daventry.Web               # a development server with the page
dotnet publish src/Daventry.Web -c Release -o out   # static files for any web server

• The page asks for a game folder; click the picture to give it the keyboard. The keys are the desktop's.
• The Sound choice offers AdLib, PCjr/Tandy, the PC speaker, General MIDI and the Roland MT-32. General MIDI asks for a SoundFont once and the MT-32 for its ROM files once (pick them all; the page finds the pair). Both are kept in the browser, and the choice is remembered.
• With "Keep in this browser" on (the default), a picked game is stored and listed under "Your games" for next time.
• The "Saved games" panel downloads saves (for the desktop player's save folder, or ScummVM's under its own target name) and imports them from either.
• ?game=<url of a manifest.json> loads a game the server hosts instead (tools/BrowserSmoke shows the manifest).
• The engines log to the browser console, where the host also prints its ticks per second; daventryAudio in the console shows whether sound is flowing (state, chunks pushed and audible, peak, underruns).
• The engines run on the .NET interpreter unless the page is published ahead of time, which needs the wasm-tools workload: dotnet workload install wasm-tools, then dotnet publish src/Daventry.Web -c Release -p:WasmAot=true.

Using the libraries

dotnet pack -c Release -o artifacts/packages builds a NuGet package for each library and host, with symbol packages, and the player as the daventry dotnet tool. tools/PackageSmoke/run.ps1 -Game <folder> checks them the way a consumer would: a console app and a Blazor WebAssembly app restore them from that folder and play a game, and the tool is installed and takes a screenshot. Pushing a tag such as v0.1.0-alpha publishes them to nuget.org through GitHub Actions with Trusted Publishing (.github/workflows/publish.yml, whose header lists the one-time setup).

An app references the engines it wants (Daventry.Agi, Daventry.Sci, Daventry.Adl) and brings a host. Without a window:

using Daventry.Agi;
using Daventry.Core.Hosting;
using Daventry.Sci;

var registry = new EngineRegistry().Add(new AgiEngineProvider()).Add(new SciEngineProvider());
if (registry.DetectInDirectory(path) is not var (container, games))
    return;

var host = new HeadlessHost();
using var engine = registry.Create(host, container, games[0]);
host.Run(engine, 600);
File.WriteAllBytes("title.png", host.Graphics.EncodePng());

Daventry.Host.Sdl runs the same engine in a window (SdlHost), and Daventry.Host.Browser in a Blazor page: <DaventryPlayer @ref="player" />, then player.PlayAsync(registry, container, game); tools/PackageSmoke/BlazorSmoke is the smallest such page. A host that implements ITrueColorGraphicsDriver as well as IGraphicsDriver also shows the true-colour video and the ADL NTSC colours.

Layout

Engine assemblies never touch SDL, the file system or a blocking main loop. The host calls Engine.Tick(elapsed) repeatedly and the engine returns how long it would like to wait before the next tick. Game data is read through IGameContainer, which can be a directory or an archive. tools holds the table generators (PortTables), the browser and package smoke tests, the MT-32 reference harness and the ScummVM round-trip notes; assets/screenshots holds the screenshots at the top of this page.

License

GPL-3.0-or-later, the same license as ScummVM, from which the engine code is derived. See LICENSE. The MT-32 emulator in Daventry.Audio/Mt32 is a port of Munt, whose licence is the LGPL 2.1 or later; each of its files keeps Munt's copyright notice.