guys , i got a big trouble,
1——let's say we have a model . the choose of model is important,models that are not rigorous enough will not expose the problem. generally 1)loop topology 2)parallel lines with changes in density(lines get close or far),like image below (there is a hip file i used attached below)
2——and now we want particles move along the direction like image below
3——that's it
-----------------------------------------------------------------------------------------------------
what i have tried is using the 【calculated v attribute on model】 to make a velocity volume to advect particles or directly using 【the calculated v attribute on model】 to change the particle‘s v attribute continually , maybe plus minpos() locking in the end.
but either failed , both make the particles have small inward deviation or outward deviation on velocity direction at every step/frame due to centrifugal force/inertia and finally make particles stick together.
what i want to achieve is particles move along these directon and the motion/trail of particles don't have any shift/offset/deviation.
all i tried just a very small part of the solutions, if you guys have any other great solution that can get the effect, please help ,it drives me crazy
particles move along topology direction_TEST_MODEL.hip
inward_deviation.mp4
inward deviation single.mp4