OpenTPW

An open-source re-implementation of Sim Theme Park / Theme Park World.

OpenTPW · File Formats

What this is

OpenTPW re-implements the engine of Theme Park World (1999) so it runs on modern computers. It reads the data files from your own copy of the game - models, textures, sounds, fonts and saves - and draws them with Vulkan.

You need your own copy of the original game. This repository ships no game content.

Can I play it yet?

Not yet. OpenTPW is a work in progress. What works today:

• The lobby works. The four islands, the front end, the advisor, weather, the options screen and your saved players.
• Only Lost Kingdom is partly working, and only from the park the game ships already built. Enter it and the park runs: guests arrive, queue, ride and buy things; you can buy, sell and move rides, hire staff and lay paths.
• A fresh, empty park does not work, on any of the four islands.
• There is no way to finish or keep a park. No finances, no litter, and nothing saves a park back.

docs/STATUS.md lists everything that works and everything that does not.

To play the original game on Linux, tools/play-the-original sets it up with Proton. You need your own disc and your own no-CD .exe.

Which version of the game?

OpenTPW is tested only with the American release, Sim Theme Park. Theme Park World, the release sold elsewhere, uses the same engine and data and should work, but is untested. If you try it, please report how it goes.

Quick start

1. Install the .NET 10 SDK.
2. Copy your game disc to a folder - see Getting the game's files.
3. Build and run:

dotnet build source/OpenTPW.sln
dotnet source/OpenTPW/bin/Debug/net10.0/OpenTPW.dll --game "/path/to/Sim Theme Park"

The build includes every library OpenTPW needs. You may also need a Vulkan driver. On Windows and macOS your graphics driver already provides it. On Linux, install your distribution's Vulkan loader (libvulkan1, vulkan-loader or vulkan-icd-loader, depending on the distribution) and Mesa or your GPU vendor's driver.

Getting the game's files

1. Put the game disc in your computer. If you have a disc image (an .iso file), double-click it instead.
2. Open the disc in your file manager, the same way you open any folder.
3. Copy everything on it into a new folder, for example Sim Theme Park in your Documents.
4. Start OpenTPW and give it that folder, as in Quick start. Put the folder's name in quotes.

If OpenTPW says the file names "have been cut short", the copy went wrong. Delete the folder and copy the disc again by dragging the files in your file manager.

If OpenTPW says it cannot find the game, check the folder you gave it. It lists every folder it looked in.

For technical users

File names. A CD holds two sets of file names. The short set is uppercase and cut to eight letters (CHALLE~0.SAM instead of Challenges.sam), and the game cannot use it. Mount the disc and copy from the mount, or use a tool that keeps the long (Joliet) names.

Where OpenTPW looks. A folder counts as the game when it has a data folder with levels inside it, in any capitalisation. OpenTPW tries, in order: --game on the command line, OPENTPW_GAME_PATH, the GamePath setting if you have changed it, the folder the build sits in, the working directory, and the default Windows install location. It does not search parent folders.

Saves go to save/ beside the game's data, where the original keeps them, so the original and OpenTPW share options and players.

Controls

Key	Does
Escape	Game menu - or, in a park, first let go of what you are holding, or leave the ground view
Ctrl+H	Show or hide the help bar
F2	Hide the interface
X	Freeze the lobby camera
[ ]	Move between islands
C	In a park: walk on the ground and look around, and back again
← →	Turn the park camera
Mouse wheel	Zoom the park camera

Platforms

Platform	Builds	Runs
Linux x64	✅	✅ Developed and tested here
Linux arm64	✅	❔ Never run
Windows x64, arm64	✅	❔ Not run recently
macOS Intel, Apple Silicon	✅	❔ Never run

Every platform draws with Vulkan; on macOS through MoltenVK, which ships with the build. Only Linux x64 is tested. Bug reports from other platforms are very welcome.

Linux on Wayland

The SDL that ships with OpenTPW has no Wayland backend, so it runs through XWayland. Scaling and input then differ a little, and without XWayland it does not start. To use your distribution's SDL2 instead:

OPENTPW_SYSTEM_SDL=1 dotnet source/OpenTPW/bin/Debug/net10.0/OpenTPW.dll --game "/path/to/Sim Theme Park"

Troubleshooting

"Theme Park World was not found." Check the folder you gave OpenTPW - see Getting the game's files.

"its names have been cut short." The disc was copied without its long file names. Copy it again - see Getting the game's files.

It stops before a window appears, saying it could not load a native library. Install your distribution's Vulkan loader and your GPU's driver.

On Wayland the window scales oddly, or SDL says "No available video device". Install XWayland, or see Linux on Wayland.

No sound. Not fatal - OpenTPW warns and carries on.

For developers

dotnet build source/OpenTPW.sln
dotnet test source/OpenTPW.sln

Most tests read the real game files and skip when the game is not found; set OPENTPW_GAME_PATH to run them all.

Launch options and the debug console

Launch options

Option	Does
--game <folder>	Use the game in this folder. --game=<folder> also works.
OPENTPW_GAME_PATH=<folder>	The same, as an environment variable.
OPENTPW_SYSTEM_SDL=1	Use your system's SDL2 instead of the one in the build.
OPENTPW_DEBUG_CONSOLE=1	Turn on the debug console.

Opening the debug console. Start OpenTPW from a terminal with OPENTPW_DEBUG_CONSOLE=1 set, then type commands into that terminal and press Enter. Every reply starts with [dbg].

OPENTPW_DEBUG_CONSOLE=1 dotnet source/OpenTPW/bin/Debug/net10.0/OpenTPW.dll --game "/path/to/Sim Theme Park"

On Windows, run set OPENTPW_DEBUG_CONSOLE=1 first, then start OpenTPW in the same window.

Commands. Most take numbers after the name, for example island 2 or step 10. Many work only in a park.

For	Commands
Going places	lobby, island, enter, park, reload, quit
Time	pause, resume, step
Lobby camera and weather	orbit, freeze, unfreeze, attract, aim, settle, near, rain, weather, strike, bolt
Park camera	camera, camcorder, facing, walk
Sound	volume, mute, sound, voices, place, speech, advisor, greet, duck
Reading the park	guests, peeps, staff, candidates, rides, vehicles, paths, arrivals, objects, catalogue, money, rings, spend, why, cell, drawn, scriptvar, bumpers
Changing guests	arrive, admit, send, load, depart, happy, cash, thirst, balloon, toilet
Building and staff	buy, put, sell, move, path, delpath, queue, delqueue, hire, fire, pickup, putstaff, carry, drop, hand, strip, tool
Mouse, keys and windows	pick, click, rightclick, rmbcancel, worldclick, hover, pointer, backspace, menu, buyscreen, hirescreen, openthing, screen, windows, control, state
Measuring	stats, assets, parks, huds, water, size, unimplemented

Each command's arguments are in DebugConsole.cs, one case per command. Add a new command to this table.

• docs/STATUS.md - what works and what does not.
• docs/QUEUE.md - the work queue.
• docs/exe/ - what the original executable does, decoded.
• OpenTPW.FileFormats - the game's file formats, documented.

File format support

❌ Not implemented    ⚠️ Partially implemented    ✅ Implemented

Format	Status
Archives (.WAD, .SDT)	✅
Textures (.WCT)	✅
Settings (.SAM)	✅
Sounds (.SDT, .MP2)	✅
Strings (.BFMU, .BFST)	⚠️ Read; a few long strings are cut short
Fonts (.BF4)	✅
Lip sync (.LIP)	✅
Particles (.PLB, .ESP, .TPC)	✅
Machine and player saves (Config.tcf, gms.dat)	✅
Map data (.MAP)	✅
Texture tables (.TCT)	✅
Models (.MD2)	⚠️ Meshes load; some animation channel kinds are not decoded yet
Sound categories (cat_*.map)	⚠️ Decoded; a few fields are unnamed
Park signs (.SGN)	⚠️ Read and drawn; a gradient fill is drawn flat
Park saves (.TPWS)	⚠️ Read, only Lost Kingdom's shipped save tested; nothing writes one
Ride scripts (.RSE)	⚠️ Every shipped script runs; some instructions are not built yet
Materials (.MTR)	❌
Video (.TQI)	❌

Contributing

Contributions are very welcome:

1. Fork the original project.
2. Create a branch named YourName/FeatureName.
3. Open a pull request when you are ready.

License

MIT - see LICENSE.md.