JoltPhysics

Jolt Physics: https://github.com/jrouwe/JoltPhysics

Note: this involves blockchain VMs. If that's a dealbreaker, feel free to skip. I get it. I've spent 8 years working on RISC-V VMs for blockchains, recently also contributing to ZK VMs. Modern blockchain VMs are drastically more powerful, and I'm curious how far we can push them. I started porting real game logic to blockchain VMs, running game loop, physics simulation, collision detection, etc., on blockchain VMs. So far I have: * Teeworlds to CKB-VM: https://xuejie.space/2026_06_16_teeworlds_on_ckb/ * One Hour One Life to CKB-VM: https://xuejie.space/2026_06_29_porting_one_hour_one_life_ga... * A small ray tracer to Jolt ZK VM: https://xuejie.space/2026_07_10_cpp_ray_tracer_on_jolt_zk_vm... Source is available for 2 of the 3, I need to clean up the OHOL one. Some context: CKB-VM [1] is a RISC-V virtual machine I designed for Nervos star

About Jolt, do you mean https://github.com/jrouwe/JoltPhysics ?

> Today the options are either free and open source (which can be extremely high quality, like Jolt: https://github.com/jrouwe/JoltPhysics) I did mention this was changing in particular with physics engines. That being said, proprietary dependencies still reign supreme in places like audio engines. Something like OpenAL isn't really a replacement for FMOD or Wwise. I know those off-the-shelf engines roll their own replacements, but then they also roll their own pathfinding and navmesh generation as far as I know.

Pathfinding middleware has traditionally been a thing though, e.g. apart from the mentioned ReCast (which is the popular free solution) the commercial counterpart was PathEngine (looks like they are even still around: https://pathengine.com/overview/). If you need to do efficient path finding on random triangle geometry (as opposed to running A* on simple quad or hex grids) it quickly gets tricky. What has undeniably declined is the traditional "10k US-$ commercial middleware". Today the options are either free and open source (which can be extremely high quality, like Jolt: https://github.com/jrouwe/JoltPhysics) or fully featured engines like Godot, Unity or UE - but little inbetween those "extremes".

The physics engine mentioned towards the end, Jolt Physics [0] is used in the frankly blockbuster games Horizon: Forbidden West and Death Stranding 2 and yet opens its description with > Why create yet another physics engine? Firstly, it has been a personal learning project. which is really rather wonderful and inspiring to see. [0] https://github.com/jrouwe/JoltPhysics

Oh, I forgot a few major ones: https://github.com/ConfettiFX/The-Forge was used in No Man's Sky, Hades and Starfield. https://github.com/jrouwe/JoltPhysics is the physics engine in Horizon Forbidden West.

Jolt physics is an amazing piece of work way above my level of understanding, but as someone who loves physics in video games I always enjoy learning a bit about how it all works: https://github.com/jrouwe/JoltPhysics http://jrouwe.nl/architectingjolt/ArchitectingJoltPhysics_Ro... http://jrouwe.nl/architectingjolt/

There is now also JoltPhysics https://github.com/jrouwe/JoltPhysics which is used in Horizon Forbidden West.

As far as physics engines go: Jolt currently seems to kinda disrupt the decades-long equilibrium, at least as far as I'm aware from my corner of the wood. I wouldn't be surprised if the physics engine landscape looks very different in 5 years compared to 5 years ago: https://github.com/jrouwe/JoltPhysics

A few years ago, as someone who has worked on physics engines for robotics simulations, I would have agreed with you. But now a lot of people are doing greenfield physics engines for games and having it work out pretty well. There's a ton of established academic and conference literature in the area now and it's not nearly as scary as it used to be. For example, Horizon: Forbidden West uses a custom physics engine that started out as one of the core dev's fun side projects: https://github.com/jrouwe/JoltPhysics Physics engines (at least game quality physics engines) are starting to drift in to "solved problem" territory and there's enough literature now that you can get something reasonable going yourself after doing some weekend reading. Edit to add: Godot has had its own engine available for a long time, so it's not a totally new effort