What is the current state of the cross-platform determinism of Unity Physics?

We are currently developing a game that would benefit from the cross-platform determinism and decided to give the Unity Physics package a go.

And it is a blast so far. Even though the physics package is still in preview, some basic build tests for platforms that we plan on supporting gave us full determinism, those platforms being: PC, IOS(Mac), Android and IOS(IPhone).

We have a plan to make a more advanced tests before proceeding, since there are lots of edge casses that we don't check yet, but in the meantime I would love to hear what's the current stance of the Unity Physics team on this matter or/and someone who might've already used the package in production.

What I know is that a solid part of the determinism comes from the marvelous burst compiler, so it's easy to assume that any device that has an exotic CPU, which is not compatible with standards and not fully supported by burst, will either fail to compile or to be deterministic.

Question to Unity Physics team: Have there been tests regarding this matter? I could make do without 1% of android devices working with our game, but close to or over 10% of devices without determinism would be a no-no for me.

 

Hi @Griz,

The Unity Physics package is deterministic on any given platform, as you have seen. Since it uses the DOTS framework, your question really is what the is current state of cross-platform determinism of DOTS. Basically as soon as DOTS and Burst in particular supports cross-platform determinism, Unity Physics naturally will too. I don't know when that will be, but you will get more traction on this question in the DOTS forum: https://forum.unity.com/forums/data-oriented-technology-stack.147. There is also a Physics subforum there.

 

Thanks Rory! Looks like that's the forum that I should originally post at. For anyone else interested in the Unity Physics determinism you can check out the new thread here: https://forum.unity.com/threads/wha...platform-determinism-of-unity-physics.922055/