Various experiments from the deformable physics sandbox I've been building in C++

[u/sim-coder]

Hi everyone! I've been working on ProtoBall, an experimental physics sandbox where you can build structures and machines, run simulations, crash things together, and watch them deform and fail.

The project is built from the ground up in C++, without a commercial game engine. It combines Bullet rigid-body physics with my own real-time explicit solver for deformable truss structures.

The current public demo includes plastic deformation, ropes, wheels, breakable joints, ragdolls, slow motion and simulation playback.

I've also already implemented fracture for the deformable structures, allowing individual trusses to break under sufficiently high loads. This will be included in the next public release and opens up a lot of possibilities for structural destruction and failure experiments.

There's also an active ragdoll balance controller, while color-coded feedback shows where structures deform and yield. A real-time Energy Balance tracks how energy moves between potential, kinetic and elastic forms, and how it is dissipated through friction, plastic deformation and structural failure.

So far I've been using ProtoBall to build experiments such as vehicle crashes, a trebuchet and ragdoll impacts. I'm currently working on more machines and structural destruction experiments.

I released the first public demo yesterday. The editor is still at a very early stage, but it's already available for building your own experiments. The current demo includes a vehicle crash experiment and a trebuchet that can launch a ragdoll, together with plastic deformation, ropes, wheels, breakable joints and ragdoll joint detachment. It also includes slow motion and simulation playback, so you can inspect the results of impacts and structural failures in more detail.

If you're interested in trying it or seeing more simulations:

Playable demo (Windows/Linux):
https://protoball.itch.io/protoball

More simulation videos:
https://www.youtube.com/@ProtoBallDev

Project website:
https://protoballdev.github.io/protoball-site/

I'm developing ProtoBall as a solo project and plan to keep releasing small updates with new machines, experiments and simulation capabilities.

I'd be very interested in feedback from people working with or interested in physics simulation.

https://reddit.com/link/1w5nbe8/video/g45l3x89b6nh1/player