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Question what's the perf impact of enabling and disabling triggers?

Discussion in 'Physics' started by laurentlavigne, Oct 22, 2021.

  1. laurentlavigne

    laurentlavigne

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    wondered if physx still rebuilds the entire world graph when that's done
    and if so, what's the best way to disable a trigger?
     
  2. Edy

    Edy

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    I haven't tested this explicitly (@yant could reply better to this), but I have a case where I need to disable and re-enable actual colliders in each frame for certain queries. The method I use is changing the layer in these colliders, run the queries, then restore the original layer. The same approach may be used with triggers. As for what I can tell, this method is essentially free.
     
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  3. laurentlavigne

    laurentlavigne

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    interesting method, I just freed up a layer so I might try that.
    do you know what the overhead would look like in the profiler?
     
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  4. Edy

    Edy

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    I don't think that changing layers would even appear in the profiler. It's just changing a flag.
     
  5. laurentlavigne

    laurentlavigne

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    What about the overhead of turning on and off the collider? How do these things show up on the profiler?