About Principia
Principia is, in its simplest form, a physics-based sandbox game. In Principia, you can build contraptions and simulate them in the physics simulation. This could be a mechanical contraption, an RC car, or a pinball game. Principia also contains a LuaScript object which allows you to write and create Lua programs that can directly interact with and affect the simulation.
Principia consists of different types of levels, available to choose from in the sandbox or on the community site:
- Custom levels allow you to create anything, with or without goals. You can create score-based minigames and let players compete for the highscore, or just build a vehicle which players can crash into with satisfying destruction physics.
- Adventure levels where you take control of a miniature robot which can do whatever you decide it to do in the sandbox. It can take part in a giant battle with enemy robots, or it can explore a procedurally generated terrain made available for you to do anything within.
- Puzzle levels where the player is given the ability to move objects around and construct their own contraptions to solve a puzzle, whether it be guiding robots to the goal or any other goal you can think of.
The Principia sandbox gives you access to 200+ different objects ranging from basic wooden building blocks to advanced logic circuits you can wire together with the game's circuitry system.
Principia was originally developed as a paid commercial game by the Swedish independent game company Bithack AB during 2013 and 2014, and was the sequel to the 2011 Android smash hit Apparatus. Unfortunately the development of Principia halted in late 2014 due to Bithack not being able to finance the project anymore, because of low sales for the game. It was however still loved by a small but passionate community that has kept the game alive after all these years.
In August 2022, Principia's source code was finally released onto GitHub and is now being further developed as an open source project by the community that grew up playing it. Principia is now free for everyone to download, use and modify under the terms of the BSD 3-Clause license. The game is currently available to play on Windows, Linux, Android, as well as experimental ports to other platforms (Haiku OS, macOS and web browsers).
There are tens of thousands of user made creations by the community to play and enjoy. Browse the latest that the community has made right now, or browse the full collection of 25000+ levels from 2013 to 2018 on the Principia official community site archive. You can also watch a collection of showcase videos of community levels, showing off interesting creations.
Download Principia!
Gallery
(Clicking on an image will give you a lossless PNG version of each)
The Principia Logo
The Principia logo features a silouette of the titular miniature robot featured in the adventure mode, layered on top of the background used in the game's menus. The frame is taken from the logo of Principia's prequel, Apparatus.
It may be a bit dated and imperfect, but remains a recognisable symbol for the game to this day.
About principia-web
This website is the community site for Principia, providing a platform for sharing user created levels and interacting with the Principia community.
Principia-web originally started as an unofficial community site replacement by ROllerozxa after the official community site operated by Bithack shut down in 2018. It has since turned into the primary community site for the game after the source code release, created by the community for the community. To read more about the history of principia-web read this blog post written by ROllerozxa.
The source code powering principia-web, as well as related web infrastructure is freely available and open source.
