Erin Catto, the brilliant mind behind the legendary Box2D physics engine, has given a the developer community was surprised when the launch of Box3D was announced.
And far from being a simple experiment, this new physics simulation engine It was born out of a real and pressing need during the development of the survival game The Legend of California at the Kintsugiyama studio. Although the team used Unreal Engine 5, its native physics engine, known as Chaos, had critical shortcomings for a project of this magnitude.
Catto se He found that thin objects rotated infinitely due to the lack of adequate gyroscopic torque, the Giant trees were falling erratically teleporting due to failures in continuous collision detection, and overall performance plummeted when trying to process hundreds of thousands of simultaneous entities on the game servers.
Faced with these and many other problems, Catto devised a way to solve this puzzle, The story took a fascinating turn thanks to the direct intervention of a Valve veteranDirk Gregorius, creator of the Rubikon physics engine used in the acclaimed Half-Life: Alyx, He suggested to Catto that they use a simplified version of his own personal engine as a starting point., named Rubikon-Lite.
When integrated into Unreal, the results were immediate and spectacular. But Catto decided to go further to facilitate long-term maintenance. To maintain consistency with his two-dimensional work, he began injecting the entire architecture and optimizations of his renowned Box2D into this new system. The end result of this fusion is Box3D, an engine where almost all the APIs and data structures come from Box2D, retaining only the complex three-dimensional collision algorithms from Gregorius's project.
With the permission of all involved, this technological marvel has been released under the permissive MIT license, written entirely in the C17 standard and with full support for Windows, Linux and macOS.
Although its first version 0.1 is considered to be in alpha phase, its capabilities are already formidable.These technologies are being leveraged by colossal projects such as Facepunch Studios' s&box gaming platform, the open-source Esoterica engine, and a massive multiplayer space simulator designed for a thousand players. Box3D shines when handling complex three-dimensional environments, offering highly accurate collision calculations with polygonal meshes and heightmaps, enabling hyper-realistic effects when interacting with destructible terrain.
Furthermore, introduces a system of pre-calculated compound collisions, A technique that allows thousands of geometric shapes to be merged into a single, optimized structure. This drastically reduces memory and processor usage when loading massive fortresses or environments filled with interactive objects. All of this is complemented by Box2D's direct heritage, including sub-step solvers for pinpoint accuracy, cross-platform determinism to guarantee identical results on any computer, and double-precision support for creating truly gigantic worlds without calculation errors.
Finally, it's worth mentioning that Box3D's future looks incredibly promising and active, as while Catto continues to refine the documentation and conduct tests exhaustive to reach stable version 1.0, It already has its sights set on expansions to support game creators..
Its Next objectives focus on improving the characters' movement capabilities, fine-tune the joint solvers and completely mitigate the annoying ghost collisions that often ruin immersion. Unlike his previous projects, Catto has confirmed that he will open the doors to the open-source community in a much more collaborative way, allowing other engineers to submit their own improvements and fixes after signing a code ownership agreement, thus ensuring that Box3D evolves nimbly to become a structural piece of the next generation of video games.
If you are interested in learning more about this new physics engine, you can find the details in the following link
For those interested in the code or who wish to try it, they should know that it is already available. available on GitHub.