Hi, thanks for your reply, i tried with the volume and the advect by volume, it moves the particles position but those particles dont seem to inherit the velocity, they stop straight after the volume, i tried the different advection type, only the position seem to do something. i'm interested in that Vexpression to drive airresist, how would you achieve that ?

Hi guys, Here the pitch : Snowflakes are falling, all of a sudden, time stop, snowflakes are in mid air, they move just a tiny bit. Only a few characters can move in the scene. Those characters are moving in the middle of those mid air snowflakes, who are advected by the movement . My first thought was to animate the time scale of my pop sim, that way the particle seems to slowly stop, which is what i want, but with that setup collision and advection didn't work. My second thought was to multiply the velocity from 1 to 0.001 in a popvop, but same conclusion, it seems that without velocity my particles wont move after advection from a geo, (which make sence, the overall velocity is multiplied by 0.001 ) Do you have any ideas how i could slowly stop the movement of my particles and advect them without using the timescale ? Thank you for your time Kind regards , Las

well, it still doesnt work here, could it come from the version of Houdini ?

Well, i believe you of course, but it still doesnt work on my Houdini. May be the version of houdini. i'll try with another.

My file reads a fractured object that i make juste before, nothing fancy too.

oh realy ? could you send me the file you use ? i should have miss something, because it's not working for me. Yes it's my file i have the geo file, but i cant upload it on the forum, may be i can send it to you by mail ?

I Tried your method, and I still have an error : " Invalid source /obj/HEAD_BASE/OUT_PASSIVE "

Hello everyone, i'm new to Houdini so forgive me if it's a stupid question. I'am following a tutorial to "control your fracture in houdini", and everything is good until, he use a certain method to make passive some blocks. The method seems quite simple, attach a point to each piece with a foreach and a centroid expression, transfert a Color attribute from an old geometry to the new one to have some black points where he wants passive blocks. after that, he use an ActiveValue sop, and put a point expression in the activation channel, and everything seems to works for him. But when I try that expression : point("../../HEAD_BASE/PASSIVE",$OBJ,"Cd",0) : I have that error : Unable to evaluate expression (Bad data type for function or operation (/obj/AutoDopNetwork/activevalue1/active)) I did some research, and apparently i'am not the only one with that error, but i didnt find any solution yet, If someone have an idea to help me, or another solution to makes some blocks of your fractured object passive. Have a nice day. fracturing_setup.hip