What settings do you guys use for Physics Cap & Rate?

I was under the impression that higher physics cap and rate means improved/more realistic physics, at the cost of performance ofc, but I usually see scenes recommend the default 72hz and usually 2 or 1 for the cap.

SortaLewd said:

I was under the impression that higher physics cap and rate means improved/more realistic physics, at the cost of performance ofc, but I usually see scenes recommend the default 72hz and usually 2 or 1 for the cap.

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I always use 1 with 72hz because animations looks way better and physics also looks more natural for my taste .

I think its important to understand how the engine (Unity) works here.

First we have a graphics frame rate, that's the rate the engine, UI and game logic runs at. Now, during that game logic update somewhere we update the physics simulation. It needs to run at a fixed frame rate to guarantee collisions work properly and avoid some numerical issues. So, we check how much time passed since the last time we updated physics (that's the same as our graphics frame rate). Now we calculate how many physics updates we got to do to keep up with the fixed physics frame rate. If both graphics and physics frame rates are more or less the same, we will usually require one update. If the graphics frame rate is higher, sometimes we won't need a physics update at all. However, if the physics frame rate is higher, sometimes we will need multiple physics updates within one graphics update. Could also happen, if there was a hiccup in the graphics update. Maybe because there was some loading for example.

So, what does physics CAP do then? Its the limit of how many physics updates can happen during one graphics frame. If you set it to 1 and at some point you need two to catch up, the physics frame will be skipped. That's good for performance, as missed updates can't pile up, but it also means physics desync from the rest of the game. When some things measure real time (e.g. game logic and sound) and other things measure physics time (e.g. animation) those can desync. Think of a dance animation that is supposed to be in sync with a music track. If you skip an update every now and then, eventually you may be 0.5 or a full second out of sync. There are ways to deal with this, but not every VaM creator knows or bothers.

TL;DR:

1. Set your Physics CAP always to the maximum so no frames are skipped during normal gameplay.
2. Set your Physics Rate to roughly your expected graphics frame rate or (if you got the CPU power or simple scene) to a multiple of that. Goal would be to have more or less consistently one (or two) physics updates every graphics frame. That's when you will have the smoothest experience.