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Found 122 results

  1. Hello, I have a really heavy flip sim of a river (around 101 millions of particles), I'm working on my final project for my master's degree. At my uni I can use only during the night as much computers as I want, each of them with 64gb ram. Since it's not possible to use the renderfarm for caches,I obviously thought to use more computers and render on each of them a specific frame range (470 frames total). The problem is that everytime a computer will start to cache, Houdini will always start to calculate the sim from the frame 1 and it will take the same huge amount of time, so what's the point to use more computers? Am I wrong? What kind of procedure would you use? p.s. keep in mind I cannot leave the computer caching after the night.
  2. Hi all, If my processor is simming and all cores are used but they are not utilized 100% does that mean the processor is waiting for the RAM to be available? Might the ram be too slow to catch up or is that the wrong way of thinking about it? (There's enough free RAM left in this sim). I saw when I lowered separation I can get the CPU usage up to 100%, but at some loads it's not using it fully. Trying to understand if my RAM is too slow, or if it's something normal. Thanks! -Johan
  3. Hii. I Have made a Pyro smoke Simulation but my Pc is damm slow. So i decided to Cache out .sim file from dopnet. After 20hrs it cache only 67 frame and Houdini got crashed. so when i reopened the Houdini and loaded my .sim file it only read from 52 frame :-( but i have cache 67 frame. any idea why is this happening..
  4. Hair self collisions vellum

    Hi I need to sim groom that needs to be quite stiff, but hair should self collide and layers should stay on top of each other. I can`t seem to make it work. Here`s simple example scene that I`m working on to test it. Any tips of how to make it work are welcome Thanks Janis selfcolision.hip
  5. Hi, Anyone knows a good way to deform groom using sim curves? as guidegroom deform doesn`t seem to work for me and pointdeform has some other issues. Do I really have to sim low res curves and then apply hairgen for full res? Problem is that i have my groom done already and want to sim approx 10% of curves and only the long ones and deform my groom by those curves. Obviously I can`t acces Furtility, so is there any other good way using Houdini to do it? Thanks Here is the simple example of what I`m talking about: groomDeform.hip
  6. pyro smoke issue

    hi I have a problem with smoke upres sim. it's normal when I cache lowres. but when I use upres to sim. the result is weird. the smoke has been cut into quarter after few frames. don't know if anyone has the same experience. I tried to solve it with change my bounding parameter setting. but nothing going good..... ( maybe the problem not from bounding box, because the bounding range in normal in the viewport. not sure....) the video and pics attached. issue_1.mov
  7. Hair Guide Transfer Issues

    Hey guys, I'm still fairly new to Houdini and I am trying to make a hair sim for a character on a short film I'm on. I have created my groom on a static mesh of the character and I want to transfer it to the animated mesh. I've imported an alembic cache from Maya, matched topologies with the static mesh, cached that matched mesh out, then brought it back in. I want to transfer the guides to this newly cached mesh, but when I use the guide transfer node, it creates multiple instances of my groom and scatters them around the space. I have also tried the vellum constraint option "attach to geometry" with only the root points selected, hoping the rest of the curves will follow but only the root points moved. Not only that, but they didn't spread across the mesh to their correct position. At this point, I'm not really sure what to do anymore. Any recommendations are welcome. I can attach the file too but I'm not sure if that would be much use since you would need the cache files too.
  8. 32GB Ram 3200mhz ryzen 5 1600 Hi again guys. Basically I have been struggling a lot with cacheing a simulation. I´ve tried .bgeo .sim and multiple resolutions on the pyro I would hate to keep lowering the res because of ram issues. I diseabled "Cache Simulation" and I still keep on feeling my Cache. I dont mind waiting days for the cache if necesary (it is a big simulation, probably 40 meters long I guess) and to be honest, I might not know in depth how to control pyros. Hopefully you can help me here
  9. Floating Fountain

    A passion project re-using footage shot a few years ago. The water is split into two sims: the first covering the sphere and the downward stream, the other filling the basin and overflowing around the sides. A total of over 7 million particles make up the fluid sim. Software used: Houdini Redshift Nuke
  10. Hi! I'm making a chocolate dipped strawberry (strawberry model from 4dm-works.com). There are 2 problems. 1) When the strawberry falls into the chocolate, the FLIP is using both bounding box of the VDB and the VDB for its collision, creating this box around. VDB resolution is at 0.007 and uniform division for collision is at 500. (which I thought are high enough?) so I'm not sure what's up. 2) The 2nd problem is that the chocolate doesn't stick to the strawberry. I have the friction, viscosity, density and stick on collision on, but nothing's been happening. I have a feeling it's something super minor somewhere.. but I can't seem to figure it out. How can I fix this? (Bound_Stick_Question.hipnc) Thank you in advance for taking a look at it! -Y
  11. FLIP SIM - How to stop bubbling

    Hi! Houdini beginner here. I'm learning FLIP sim and having trouble with it "bubbling" at the end. It's a water-filled glass breaking (bubbling_question.mp4). Towards the end, the liquid is constantly moving and is creating this "bubbling" look. I've tried adding a POP Speed Limit after certain frame, or setting POP Velocity to 0 after certain frame, but nothing seems to work. How can I fix this? (I attached the hip file but I'm not sure if it'll work due to missing geos and caches: bubbling_question.hipnc) Thank you! -Y
  12. RBD sim and orient

    Hello guys. Recently i have run into strange issue. I have my packed objects, that have some orient on it. I need to feed them into the Bullet sim, problem is that if i have orient as attribute on the packed objects, my sim explodes on first frame (no intersecting geo), if i remove my orient, sim behaves as expected. so i have run my sim without the orient coming to bullet (renamed orient to keep_orient) and i thought i will just substranct+add them at the end to get correct orient values for my instancing i do as next step. Problem i have is that i was not able to get correct orient from it. Would someone able to explain me what would be necessary to do to make it work, or why bullet explodes with orient values? sorry i cant share any scene at this point. my whole setup is: points in the space, that have @pscale and @orient (random nodes), that goes into the grain sim, to make sure i have no intersections, then i do copy bunch of rocks onto those points which goes as packed geo into the bullet sim.
  13. Hi Everyone, I'm trying to setup a TOPs network to cache out sims with multiple parameters being sent to the dop network. Seemingly basic stuff, however nothing I'm doing seems to be working how I think it's going to work. What I've tried: Using a wedge node to set a random attribute and trying to use that attribute in an exterior dop network - caches into a view able geo rop output but all the wedges were the same Rebuilding the pyro sim purely in the tops network - it makes something but when viewed all the frames appear empty Have the source inside the tops and the dop outside - same result as the first
  14. Vellum Sim With Changing Point Count

    Hey guys, I've tried many different ways, but I can't seem to find any stable way to run a vellum softbody simulation with a object (in my case a meshed vdb advection growth) with a changing point count. I've tried brute force with a solver SOP to run over it every frame, but with no luck. Would love to see you guys tackle this. Cheers! -Isaac
  15. Whitewater h17.5 Not to emit bubbles

    Hello, Using Houdini 17.5 to create boat wake with white water. Using the white water solver I where I would like to emit foam and spray over the flip surface. However, I do not want the bubbles as I am under the impression this would reduce simulation time and memory consumption. That said, I couldn't figure out a way to stop the solver from emitting bubbles! Anyone was able to deal with this or any documentation or thread that could help?
  16. Hey guys, I'm having some headaches with the new rig. Worked fine for the first 3 weeks but now I'm getting random errors (I asume are memory related). I'm working with 112gb ram because 1 slot is broken, I've heard having 7 in use and not all might cause performance issues, that I better work with the half slots at 64gb. Will run memtest86 and windows diagnostic (wich I ran before with success), but wanted to hear opinions about best way to troubleshot this. Thanks!
  17. Freeze Flip Sim

    Hey Guys, Imagine an object which fills with liquid over time. When the object is full of liquid i want the motion of the Flip Fluid stop oder decrease over time. For example: - Object fills with Flip Fluid from Frame 1 to Frame 96. - Liquid and all motion of it slows down from Frame 96 to Frame 144, at Frame 144 everything is not moving anymore. I tried some pop wrangle inside my DOP but i cant get this working. Any suggestions? Should i do this after the DOP in SOP Level in a Vop/Wrangle or could I achive this inside my DOP? And How? Thanks and Greets, me
  18. I'm working with a wie simulation at the moment and would like to save out frame 300. This is ofcourse easlily done by saving out the frame with a file cache. However, The wires I'm imulating change patern per frame. So the input for the simulation changes when I try to run it. I would like to save out the simulation frame 300 for all patterns. so say frame 1-10 I load in 10 diffrent patterns and want all of them to cache after 300 frames of simulation. basically the end result would be: (where $F = 300) Pattern-1-Simulation.$F.bgeo.sc Pattern-2-Simulation.$F.bgeo.sc Pattern-3-Simulation.$F.bgeo.sc Ect. I can manually do this by making the input static and waiting for the sim to run, but the sims take about an hour and a half and I would like to just leave that on at night. I'd preferably like to avoid having to make 10 filecache nodes with 10 diffrent inputs and ROP-merge outputting them, though if this is the only way then maybe. Any help?
  19. Animated Vellum constraint

    Hi everyone ! So I am working on a scene where i need to sealed vacuum a building and make the cloth breath :/ So The vacuum part work well but everytime i try to animate the constraint inside my vellum solver it's get crazy.. Does someone now how to animate constraint or if it's possible ? I'm linking the scene file untitled.hiplc sorry about the poor english not my first language... untitled.hiplc
  20. Hi Guys, Very new to houdini so spare the studpidty, Ive set up multiple rocks in sops using the copy to points node. I wish to then perform a rigid body simulation on these rocks so that they collide with both the ground plane and each other. However, the effect im achieving is the group of rocks falling and interacting with the ground plane as a single large grouped entity. This is despite me setting the bullet collision data as concave and not concave. Thanks in advance all! Procedural Rocks.hip
  21. Dear all, The plot : -> Am currently simulating a simple shatter with rbdPacked prims + Constraints Glue + a gorund plane, all into a DOP. (nothing Awesome till here). The Questions : -> But, strangely, the little rbds continue to vibrate once fallen on the ground. It looks like continuous vibrating tiny giggly wiggly inter-collisions. Did any body ever had this ? Would it be possible, i've to FORCE STOP them using a desactivating VEX snippet in a DOP/geomety wrangle node ? If anybody had this one time, let me know, please. You will be welcome and it will be pleasure to discuss that point you. Thank you all a lot, cheers.
  22. Crowd with flares

    Hi, i have single smoke flare sim, and i need somehow attach it to crowd agents, to be able randomly time shift smoke with agents. Any ideas will be appreciated, thanks!

    Hello Dear Houdini Community, I have been trying for hours to solve this problem. I have a simple simulation with grains, the basic idea is when the particles touch the surface more often they stick to it. they do not do that, they all disappear to one point in the scene, actually always 0, Y value, 0. Can someone look at it? Sincerely, Tim grain_test_collision_stuck.hip
  24. Hi everyone, i got a question and can't figure a way out. Imagine a bottle, and a mesh that perfectly fits into that bottle. I want to convert the mesh into a flip fluid and when i turn on gravity i want it to be as big as before. So my bottle is filled. The reason why i want that, is that I have a drop coming from above and falling into that bottle. When it collides with the fluid inside the bottle, I want a little splash and then the sim is done. How can i get a filled bottle that stays filled after I turn on the Sim. Maybe someone got the same problem or a solution, but i can't get my head around it! Thanks and Cheers!
  25. Hey everyone, I'm looking for a little help on a pyro sim I'm doing. I've got a fuel and temperature source that move along a path, emitting flame. The goal is to make a look like the flame is propelling an object forward, like a jet engine. I'm able to achieve most of this easily enough, but my sim has a lot of wasted space because the sim container doesn't rotate with the movement of the source. This really slows everything down and it's driving me crazy. I've tried a few things that used to work in H16 (the "point position" node specifically), but H17 sources volumes differently and won't play nice (the sim will rotate the already rotated source volumes again). Most of this I learned here https://gumroad.com/l/TqUNR, which no longer works properly with H17's volume sourcing. Anyway, if anyone could help out with this it'd be great. inverse_transforms_6.hip