16-12-2019, 06:45 PM
(This post was last modified: 16-12-2019, 06:50 PM by josemendez.)
(16-12-2019, 06:07 PM)Noblauch Wrote: Thank you for your quick response and explaination!
Setting the Maximum allowed Timestep down really helped to get the calls per frame down which is great. I'm still optimizing the wohle szene, which contains some heavy rendering which triggered the spiral in the first place I guess.
But if I set the "Substep Unity Physics" on true again, one ObiFixedUpdate() takes about 1.5 - 2 ms, which is quite much for that little amount of vertices in my opinion. My machine is running a i7-8850H.
I'm still trying to get used to Obi Rope, it's overall a great plugin and I had it on my list quite a time now. But there are still some behaviours that I can't really explain to myself.
Greetings,
Nils Ole
"Substep Unity Physics" basically substeps the entire Unity physics loop too to keep both Obi and Unity in sync, so these extra 1.5-2 ms are actually the entire physics update of your scene. So a big performance impact is of course to be expected as you're now calculating all physics (colliders, rigidbodies, etc) more than once per frame. This is needed if both engines are expected to interact, as you cannot update different objects at different timesteps if they take part in the same simulation. Well, technically you can, but stability then goes out of the window.
All of this is not exclusive to Obi. Pretty much all game engines in the market approach physics using a fixed timestep of a semi-fixed timestep for stability reasons, so there's not much we can do to simplify it. You can ignore most of it if your game doesn't use physics or uses very basic physics... but as soon as you need something more than a character running around a static level or a few crates, deeply understanding fixed time stepping is a must unfortunately.
