Docs clarification regarding Max Physics Steps By Frame

[rabidrabid]

Godot Version

v4.2.stable.official [46dc27791]

Question

The documentation regarding Max Physics Steps By Frame states the following

. . . the game will appear to slow down if the rendering FPS
is less than 1 / max_physics_steps_per_frame of physics_ticks_per_second. 
This occurs even if delta is consistently used in physics calculations.

To avoid this, increase max_physics_steps_per_frame 
if you have increased physics_ticks_per_second significantly 
above its default value.

I don’t quite understand how the 2 variables relate to each other. I was planning on increasing physics_ticks_per_second (for an internal experiment) dynamically and temporarily by code, but it seems as I have to take into account this other variable, max_physics_steps_by_frame and I don’t quite understand how.

Like what is the formula to take into account, if i set, let’s say, physics_ticks_per_second to 80 how much should I increase this other max_physics_steps_by_frame variable and stuff like that.

[Calinou]

If you increase physics ticks per second to 80 without changing the FPS threshold at which the game starts slowing down, you should increase max physics steps per frame by 80/60.0 which is roughly 1.333x. You’ll have to round the final result as Max Physics Steps per Frame only accepts integer values.

[rabidrabid]

Aaah I see! So the result of that division is the factor by which I should multiply the MaxPhysicsStepsByFrame.

So in that same case, as the default value is 8 I should multiply it by 1.33333 then I get 10.66666 so I should set it as 11 (rounding), is this right?

[Calinou]

@rabidrabid

So in that same case, as the default value is 8 I should multiply it by 1.33333 then I get 10.66666 so I should set it as 11 (rounding), is this right?

Yes