Real-Time Soft-Body Car Crash Physics Prototype (Godot + Jolt Customized)

BacheyG

Hi,

I’m working on a car crash / vehicle damage prototype in Godot and wanted to share a short video of the current state.

All deformation and damage is computed in real time. There are no pre-baked animations, mesh swaps, or scripted damage states. The main goal so far has been physical plausibility, deformation persistence, and keeping the simulation stable and fast enough to run well on older hardware.

The demo runs smoothly on an older iPad, so most of the work has gone into keeping the system lightweight and predictable under repeated impacts.

What’s in the video:
• Head-on and angled wall crashes
• Vehicle-to-vehicle collisions (including T-bones)
• Repeated impacts to show damage persistence
• Collisions against different masses and rigid obstacles
• Some slow-motion segments to make deformation easier to see
I just tried to emphasize the variety and correctness.

Vehicle control and damage & deformation is a custom system built on top of Jolt

This is still experimental, but I’d appreciate any feedback, especially if you’ve dealt with physics-heavy or performance-constrained projects in Godot.

Video:

Thanks.

Tomcat

A very interesting project. It looks very promising. Unfortunately, it should be noted that physics in the game engine is quite ephemeral. It is calculated based on physical frames. Example: a bullet flies at a fairly high speed — in one frame it is in front of the glass, in the next—behind it. The glass remains intact, which cannot happen in reality. Relying entirely on physics is not a universal solution. In this case, a ray is usually used. And you always need to decide which approach to use in a particular case.

I want to use physics in my work, so I will be following this project closely.

BacheyG

Discrete physics and fixed timesteps definitely have their limits, especially for very fast-moving objects (the classic tunneling problem you describe). In practice, I don’t rely on a single approach everywhere. It’s more about choosing the right tool for the situation.

For vehicles and large rigid bodies, the current setup works well and stays stable even under heavy impacts. For cases where high-speed contact precision matters, hybrid solutions (sweeps, rays, or custom queries) make more sense than pure rigid-body contact.

So far, it is performing pretty stable, but the development is in an early stage and I'd like to fine-tune and add more details and fun stuff/content later.

Tomcat

BacheyG Are you planning to introduce destructibility of objects [1, 2], or will you limit yourself to deformation only?

BacheyG

Not my top priority for sure, there's a lot of refinement I would like to finish up first, but I certainly have some fun ideas for the mobile game I will release.

kuligs2

BacheyG i wonder, who are gonna be the people who play mobile games? You mean thos people with attention span shorter than mosquito fart?

Will this not see desktop release?

BacheyG

kuligs2

Mobile is mostly a constraint choice, not a statement about players. Targeting mobile forces the system to be efficient and robust under tight performance limits, which is useful even if the end goal is desktop. It also makes iteration and testing much faster. That said, yes: I do plan to support desktop in the long run. Mobile is just a good proving ground for the tech right now.

axolotl

Impressive work! This is very cool 🙂

MikeCL

Would be really cool to see a small "Destruction Derby" inspired game with this 😃

kuligs2

MikeCL or "Demolition Racer"

BacheyG

MikeCL Yes, I have some ideas! 🙂