Increasing solver sop substep accelerates animation speed

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Hi.

From what I know, higher substep means a solver will break a frame into various segments for more detailed sim. But I didn't know it could speed up a sim and this is what's happening with my tiny task.



Those scattered points should rotate around the center and it gets perceptibly faster as I increase the substep of the solver sop from 1 to 3. Can anyone explain what's happening here please? Thanks for help in advance.

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substeps just means it calculates more than once per frame. The solver would need to respect the different time step in some way to be invariant. A naïve system will run 3 times faster with 3 times as many sub steps.
Edited by jsmack - Nov. 13, 2020 19:01:59
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in the Wrangle you can access the current timestep (in seconds) using @TimeInc binding, it will account for solver substeps
so you can directly multiply your speed value with it to get the amount for the current substep
if you want to keep your speed value in frames then you'll need to multiply by fps, but for simplicity in this example speed represents units per second

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Tomas Slancik
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Method Studios, NY
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