POP instanced geo jittering

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When I instance objects on particles they jitter, i cant figure out what wrong. Im sending hip file

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pop_test.hip (407.7 KB)

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Your copies are jumping around because your point numbers are not constant. There are two culprits in play. One is you are using the default scattering of the PopSource node. This means the frame number changes the seed on the scatter inside the node. A better approach is to pre-scatter points with a static seed before you enter the popnet and reference All Points as the pop source. This way you control where the points are generated from. The other culprit is Reaping. When a particle dies, it's id number is reused and thus generates a new object in a new location causing a jump to occur.

If you pre-scatter and disable reaping you get less jitter out of the particle system. However, with reaping off you must manually remove particle from the system, id needed. For instance…
if(@P.y<0) removpoint(0,@ptnum);
Will remove particles that fall below the world ground plane.
Edited by Enivob - Nov. 6, 2018 10:11:28

Attachments:
ap_pop_test.hiplc (417.4 KB)

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