Unity Bullet Physics (Letter to the Community)

Community Showcases
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See the following links for context.

Unity-Bullet-Physics-Plugin-Demo
Basic-Demo-Unity-Bullet-Physics

Letter to the Community,

I just wanted to thank everyone for their interest and feedback in Unity Bullet Physics. I also apologize for being dormant for the last month. About a month and a half ago one of my other prototype projects was funded by the DoD (mostly after hours work) and I also just returned from my honeymoon. I think I have a plan on how to make this work for everyone and I wanted to run it past everyone before I took any action.

Originally I was planning on making the project open source after I completed v1 and charging for the pre-built binaries (android, win32, …) on the asset store. In addition I would try to run it like the more successful open source business models (free software, paid support/features.) Now that my free time has been acquired this is not going to work for me; at least at this point.

Plan B. I was already working on refactoring the prototype into something that could be open sourced and integrated into the bulletphysics.org repo. Thus, I could open source the project before v1. I need to discuss merging this into the Bullet Physics repo with Erwin Coumans, the Bullet Physics maintainer, but worst case I’ll just put it on github if it can’t be integrated into the main repo (or maybe its too early to merge into the main repo.)

In addition I’m also floating the idea of making a Kickstarter project for the concept. Something to get Unity Bullet Physics into a solid v1. This could free me up and hopefully others into getting to v1. I think the good thing about this is that I could spend a weekend documenting all of my ideas and create a promo video with some of the samples I’ve created.

All in all, this has been a fun project. I really hope that I get to finish it (because of how much I hate PhysX; heh) in a timely manner, but I’m happy to work with the Community to find other ways for it to survive. I’m always open for suggestions.

V/R,
Bourke Floyd

Unity-Bullet-Physics on Facebook

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I was looking forward for your release. Especially I wanted to test the gpu performance.

Whatever plan you follow I am intersted in it (be it kickstarter, asset store or open source).

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May I ask why you hate PhysX? Many AAA games use it.

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The version of PhysX embedded in Unity is rumored to be very poorly optimized by NVIDIA for CPU performance, and I’ve seen first hand a lot of work go in to working around PhysX performance problems on larger projects.

Also just having more control of which physics engine is used would allow more flexibility for certain projects, such as networked games writing their own non-unity based dedicated server with a unity-based frontend client and it’s useful to have the exact same physics engine running.

Plus it’s just a cool project, so I support this guy. :slight_smile:

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I see. Thanks.

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Hi chbfiv,

Thanks for all your work on this so far. A key reason why I’m so interested in this is that I’d like to use it to implement double floating point precision into Unity for large regions.
I’m wondering if you can take a guess at how difficult this would be to implement properly? After replacing the physics engine in Unity would we still run into any core components within Unity to stop double floating point precision?

Thanks mate.

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strich,
Bullet does support double floating point simulations, but I’m unsure if Unity has support for this. I could build unity bullet physics for double precision, but you would only be able to use the internal simulation classes, not the unity workflow classes that tie to the unity classes.

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kersk,
Thanks. I agree with you across the board, though I haven’t had a chance to test the performance changes to 4.0 yet.