Hello @jenandesign,

Thank you for reaching out to us. Please make sure to consolidate updates to an initial question into a single posting in the future. It makes it much easier for others to explore a topic. And while providing a scene file is much appreciated, we must insist on code also being shared in the thread, so that others can evaluate a topic quickly. I have done it here for you.

About your Question

You are right, this is indeed related to the bug you mentioned. Unfortunately, the bug has not been fixed. I gave the ticket a little bump and marked this thread as to_fix, so that we can track the issue more closely.

In the meantime, you could put the effector in Parameter Control mode where this problem does not occur. One is here limited to adjusting the transform which has been defined under Paramater of the effector, but adjusting a fixed transform by the index of a clone is entirely possible.

a74eb64a-7820-439e-9684-17a20f9d395f-image.png

Cheers,
Ferdinand

File: rnd_modulo.c4d
Code:

"""Demonstrates how to only transform particles at a certain index with a Python Effector in Parameter Control mode. """ import c4d import math op: c4d.BaseObject # The Python Effector def Hash11(x: float, seed: float = 1234., magic: tuple[float]=(1234.5678, 98765.4321)) -> float: """Returns for #x a pseudo random float hash in the interval [-1, 1]. We could also use random of Python for that, but we would have to initialize the hash table for each call with random.seed(particleIndex) to ensure a persistent result, which would be VERY slow. """ return math.modf(math.sin((x + seed) * magic[0]) * magic[1])[0] def Hash13(x: float, seed: float = 1234., magic: tuple[float]=(1234.5678, 98765.4321)) -> c4d.Vector: """Returns for #x a pseudo random vector hash in the interval [(-1, -1, -1), (1, 1, 1)]. """ xc: float = Hash11(x) yc: float = Hash11(x + xc) zc: float = Hash11(x + yc) return c4d.Vector(xc, yc, zc) def main() -> c4d.Vector | float | int: """Runs the example. """ # Get the MoGraph data for the effector. moData: c4d.modules.mograph.MoData | None = c4d.modules.mograph.GeGetMoData(op) if moData is None: return 1.0 # For all particles in the position array ... if moData.GetBlendID() == c4d.ID_MG_BASEEFFECTOR_POSITION: # apply only the transform to each 4th particle in the array. We also do some randomness, # as your file name seemed to imply that this was your goal. pi: int = moData.GetCurrentIndex() return Hash13(pi) if (pi % 4 == 0) else c4d.Vector(0) return 1.0

Where to report a bug?