Will rigid body physics get a better algorithm?

With the latest news of mantaflow and better cloth simulation, I was interested in looking at how to do simulations. After playing with rigid bodies, I thought about experimenting with other programs seeing how close could a simulation with the same parameters look, or looking at what parameters were the standard, etc…
While what we have might work for most simple cases and look plausible even in complex ones, is NOT accurate.

Rigid bodies should have 3 paremeters: Static friction, dynamic/kinematic friction and bouncines.
Blender rigid bodies only have friction.

Here are some old threads addression the issues about it long ago. Is nice seeing other addons doing more complex things, but no one seems to have given the attention it deserves to the most basic kind of physic simulation.

For reference, I thnk is also relevant looking some articles on wikipedia about the rigid bodies

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I doubt that anybody will come up with a “better” rigid body library than Bullet anytime soon, because Bullet is not at all as bad as you might think. It is based on real world physics and scientific papers, it even simulates static friction within the limitations of a real-time engine (which needs to be performant). Friction simulation could be better but in the end you have to decide if you prefer speed over accuracy or rather something very slow but more accurate.

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Indeed…
The Bullet solvers are very advanced and uses in a -lot- of 3D applications, games and simulation applications.

There are commercial options out there, but Bullet is in no way as bad as you state.

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Good to know it’s not that bad, at least in a realism/fidelity sense. I tested blender against C4D and Max. C4D simulation looked almost exactly as blender. On the other hand Max wich has static friction looked very different, even with different parameters I couldn’t get objects to slide over a plane with lower friction.

Today I could finally set a Maya simulation as well (I couldn’t import a fbx in correct scale so I had to scale it by hand) and looks like it also uses the Bullet library as blender does so yeah, it might not be bad indeed. But Maya has a parameter for static friction, even if that’s not accesible in blender… weird

Edit: I also read the wikipedia page, and I’m surprised that it’s on so many apps, as houdini or C4D, which didn’t have a setting for the static friction available either.

There’s a lot of things in the bullet library that is not in blender. I’d say its more a blender thing than a bullet thing

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So basically your ‘issue’ with Blender’s implementation of Bullet is that is lacks the ‘static friction’ option?

If so, this could be for several reasons. Instability when added, it was not there at the time and they kind of forgot about it. Raise a voice on the dev channel or rightclick forum. Maybe they will implement it soon. :wink:

What does houdini use?

Bullet is one of the solvers you can use in houdini.

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