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Question Particle system noise causes particles to slowly drift away

Discussion in 'General Graphics' started by BakeMyCake, Nov 1, 2022.

  1. BakeMyCake

    BakeMyCake

    Joined:
    May 8, 2017
    Posts:
    175
    I'm trying to add random jitter on otherwise immobile infinite lifetime particles, so that they oscillate back and forth in place. In order to do that I tried activating the Noise module, and it appears to do the trick at first, but if you leave it for a while you will notice that through those oscillations the particles slowly drift away from their initial position (which is undesirable).

    Particle system:
    • Duration 0.05
    • Start Delay 0
    • Start Lifetime Infinity
    • Start size 0.02
    Emission:
    • Rate over Time 0
    • Rate over Distance 0
    • Busts 0, 200, Infinite, 0.010, 1.0
    Shape:
    • Shape box
    • Emit from shell
    Noise
    • Strength 0.1
    • Frequency 1
    • Scroll Speed 4
    • Damping off
    • Octaves 1
    • Quality Low
    • Position Amount -2, 2 (random between two constants)
    After 186.37 seconds I can clearly see the particles drifted away from their initial placement.

    How can I get rid of this drift? I want particles moving back and forth returning to the same spot
     
  2. richardkettlewell

    richardkettlewell

    Unity Technologies

    Joined:
    Sep 9, 2015
    Posts:
    2,285