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Found 327 results

  1. Donuts & Cupcakes! What? This is the theme of my new 3D animation [V2] of dominoes falling down! The goal? Have fun and training my skills in 3D simulations under Houdini v18! Technical details : - Houdini 18 -> Modeling, textures of Cupcakes and Donuts, rigid body dynamics simulations, placement and cameras paths. - Blender 2.83.1 -> Textures, lights and rendering with Cycles, because Houdini's mantra is really too slow to calculate ... Now enjoy it and leave me likes and comments, it's always a pleasure !! Here : https://www.youtube.com/watch?v=0sFKkirxTbk
  2. Hello, fairly new to Houdini here, I am having problems with a simulation. It should be fairly simple. I am simulating a animated object that is coated by a fractured RBD object and fracturing the object by using a SOP solver by Group Create with Bouding Objects and Attribute Wrangle with 'i@active = 1;' This simulates fine, except the Animated Static Object becomes active when a bounding object covers it and is triggered and starts to wobble around inside the half fractured coating. Is it possible to keep this Animated Static object from being activated? Any help would be appreciated.
  3. I wanna create a slicing simulation in Houdini. But somehow my free falling soft body after a few frames, just jump back to the original position. SLICING_02.hipnc
  4. Simulate an object covered in goo

    I want to simulate an object covered in a goo or mucous-like fluid. The fluid would need to stick to the surface of the object, but still be possible for some of it to break off on collision or slowly drip down from gravity.I'm not sure how best to achieve this. I was considering doing it in POPs and meshing the result, but I would like to have the detail that a FLIP sim would give. I'm also not sure how to get the particles to strongly stick to the surface while still having the possibility of breaking dynamically. Any ideas of where I could start?
  5. I have a vellum cloth object set up in DOPs. I want to add an animated pin to target constraint. I can get this working in vellum solver SOP just fine, but I can't figure out how to set it up inside a dopnet. I've tried setting this up multiple ways, and I'm not sure what I'm doing wrong. (HIP and screenshots attached.) I would also like to know how to specify target geometry in DOPs. dops_pin_example.hipnc
  6. Hi everyone!!! Started to study houdini. I have separate elements with velocity setup as I want, but couldn't find a way to add any one of them to drive flip fluid. How can I add a velocity of the mesh or curve or the volume to the flip fluid? Or maybe someone can share a tutorial about how it works? In the end trying to create a chocolate swirl or vortex. Thanks.
  7. Hi all, I'm looking for a solution for an RBD Problem. I'm trying to generate cracks on Object with the shortestpath SOP, which than wil be used to animate the growth of the crack and also will be used to cut out the crack deformation on the surface. In the next step I'm trying to create a first fracture along this cracks. If I use the data I get from the shortest path, my Fracture doesn't work because the Geometry is not Fractured completly trough. If I modify my shortestpath to generate my cutting planes, my pieces don't align with the "modeled" cracks at all. I'm sitting on this problem for more than 2 weeks now made no progress and I'm out of ideas. attached is my setup and a file which shows the idea worj´king but on a Flat wall not a round 3D Object. I already check this Form for solutions but I only could find topics where people asked a similar question but got no answer or topics which are old and outdated. I'm trying to create something simular to the Topic below. If someone could find time to help me it would be very much appriciated. cheers Cracks_with_Fracture_help_02.hipnc dm_wallCrack.hip
  8. Particle Sim Crashing

    I've tried caching out a particle sim multiple times each time it crashes at frame 190 of 240 and gives this error. Does anyone have any idea what this could be? crashLog.txt
  9. Vellum Grains - POP Spin / POP Torque

    Hey folks, simple question... is it possible to use the POP Spin or POP Torque (DOP Nodes) on a Vellum Grains sim. I am emitting Vellum Grains continuously and after the sim i use the Grains to copy f.e. Boxes onto the Points. But i can't get the Geo to rotate. They stay static at one axis and don't rotate. So my question is: Is it possible to use POP Spin or Torque on Vellum Grains? Cheers
  10. Hi there, I want share for free my HDA for combine and export the cache of fluid from cluster system and convert it in VDB. Download here It's a open HDA so you can edit it if you want, please let me know if you do/did it and let me know if you use it in production. It's free, but a little donation is grateful Have a nice day Matteo video demo https://youtu.be/dLj2CaWam7Q
  11. I have a simple problem, but do not know hou to do it. I want to color my sphere with created vector attributes, and let it change frame by frame based on the points of color vector I created as shown in the geometry spreadsheet. It should be easy to do? But I am a newbie, have tried many ways but failed. Thanks a lot!
  12. Upres external simulation

    Is ist possible to make a simulation in embergen, export as vdb, import into houdini, and upres the simulation using gas upres? (you have density, temperature, vel, fuel and heat)
  13. Hi everyone! I'm currently going through the Procedural Cities in Houdini Tutorial from Pluralsight. So far everything worked out great. I had to adjust some nodes (As the tutorial was made in Houdini 15) But it's working. I'm now in the process of aligning bounding boxes of Buildings to the geometry surrounding them (e.g. rotating the buildings so they face the streets) Using a bulletsolver and popattract. In the tutorial video this simulation runs smoothly... when I'm opening the exercise files on my Computer it runs fine too. But with my own file the viewport runs slow (like 1 frame every second) The perfomance monitor shows this: (The dopimport took even more time but I bypassed it here to see if the problem was somewhere else) I'm not sure where to check for the __DopDetailLook_Guide or how to influence it. But it seems to be viewpoert related, as entering a framenumber in the timeline simulates super quick and gives the right result... So this isn't really breaking anything as I can get the correct result anyways without waiting forever, still I would love to know why the simulation runs so poorly in the viewport. If anyone wants to see the hipnc file I'm happy to upload it somewhere. Any help would be greatly appreciated! Cheers! Daniel
  14. Hi guys! I started houdini 3 month ago so sorry if my question is dumb but I'm really stuck on a problem for 2 hours now: I want to export an .obj file from a simulation (just one frame of the sim), so I tried many different ways: rop geometry, writing file, save the geo folder itself to gallery... But nothing is working and I can't find a way to solve this problem! I searched on the internet and there's almost no one speaking about that... Btw I'm using the apprentice version of Houdini so I can't use alembic files... I give u my project file so u can see more clearly what's going on. Thanks for helping Chain.hipnc
  15. object scale change, durring rbd sim

    Hello, Houdini folks! I have a question about very essential thing durring the rbd simulation. (Im attaching the file here). What I have, I want to change the scale of the pighead, durring the simulation, but without this "strange jumping" behaviour. Any suggestions, how to solve? Thank you so much. strange_behavior.hip
  16. I'm looking for alternative workflows for defining attributes on a tet mesh for FEM simulation. Normally I would use intersecting volumes to define regions inside a tet mesh. But for my current purposes that would require producing some pretty complex geometry. The ability to paint these attributes would be simpler. For instance, it might be nice to be able to paint an attribute on the surface and have it penetrate the tet points at a given depth. (Though even if that were possible, I'm not sure how you would access deeply interior points that are not close enough to the surface.) What methods do you use for assigning attributes to a tet mesh?
  17. I am trying to render a simulation done with a flip which is made up of 22 million particles. After having made several attempts the houdini console throws me a: 9576: Fatal error: Segmentation fault Saving application data to .... Here below I leave the image and the project files in case someone is willing to help me. Thank you so much!! Help me please!!! Collider.obj Test.hipnc
  18. Hello! I'm following this tutorial: and have been getting similar results up until around 22:10, when my simulation behaves entirely differently. My worm just goes flying. I've messed around with the values in the set_force attribute wrangle inside the sop solver, but can't seem to get anything like what he is. Obviously it's working to some extent, because a force is being created. I'm pretty sure I did everything the same as him... can anybody help me out? Here's my file:Larva2.hipnc
  19. Vellum + other simulation (rbd)

    Hi all, I am trying to figure out a way to let a vellum simulation interact with other simulations. In this case I want the vellum donut to collide with the chain simulation I made. My thinking was to do this through a dop import field. However there is no collision between the 2 simulations. Does anybody know how to achieve this interaction? Cheers! Chain+vellum.hiplc
  20. Hi everyone, I am trying to get an animated collider to contain the smoke I am emmiting inside a tube. I am deleting some polygons over time to let the smoke gradually escape from my tube. The problem is my geometry collider doesn't update even if I turn on "use deforming geometry". So I just have smoke inside my container, but nothing go out from it. If someone hasa clue it could be awesome <3 (you can find the hip file in the post) Thanks Smoke_Animated_Collider.hip
  21. hello guys! I have a pop sim that runs for like 30 frames as they fall .. then I want to revert(attract?!) them back to their initial position (as they were before falling)... I tried the per point attract on the attract node.. and I get their positions back .. how can I get their orientation also to be targeted to the initial orientation?
  22. Hi everybody! I'm new to Houdini and I'm using my time during the lock down to go deeper into it. I have been trying some different vellum sims and I was feeling ready to try a new one. I just wanted to make a new r&d project where a sphere passes through a torus or a hole. I found this example online. At second 15 you see what I mean. https://www.stashmedia.tv/digital-design-days-trailer-ditroit-directors-cut/ Is it possible in achieving this shot in a single simulation or in your opinion it was made with FEM in two different settings and then edit like a single shot? Please let me know I'm dying trying how to do it
  23. Hello Houdini Magicians, This little bit of code is, according to the performance monitor and some debugging, slowing down my simulation... alot. Specially with a high number of particles. The nPt comes from the nearpoint function. I analyzed the performance impact of the nearpoint function with many particles and it is not significant. Its the conditions and moving/removing particles from groups. What is the optimal way to do this?
  24. Hey all, it's first post here and new to Houdini so I appologise if this isnt the easiest to follow. I have been trying to create a robust system for controlling vornoi fracture points, their glue strength and a way of manually breaking constraints between points. Ive been following some tutorials piecing together relevant bits from each to try and achieve this. My current issue Im facing is that once I play the simulation and the constraints start breaking they start flickering back on and glueing parts of the object which have already been broken. From my undertanding I think the manual breaking of constraints which is conflicting with the remove_broken SOP solver within DOPs, but I can't figure out how to get them both to work together. Any help would be greatly appreciated as I've hit a brick wall with this. Ive provided my scene file - I hope it's all easy to undertand. Thanks. Fracture_v001_notworking.hiplc
  25. Hey guys, trying to figure out something that's probably simple (I hope). I'm making a small edit to the sopsolver inside a POP source object. Just adding a wrangle to ignore some points, sometimes. Specifically, per substep. Unfortunately I can't figure out how to get the substep number from my wrangle. To recap, I have added an extra wrangle into the SOP Solver inside a POP Source node. Trying to access what substep the sim is on, and @SimFrame doesn't work (which makes sense). How should I do this? Thanks, -M.