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Found 213 results

  1. Contract A Rope (Vellum)

    Hey guys! I want to create a simulation similar to this one, where the ropes contract and interact with a softbody: I'm well aware that he used c4d for his simulations but I would like to replicate it in Houdini, probably with the new vellum tools. But I can't seem to find a way to contract a vellum cloth sim, animating the rest length from 1 to 0 doesn't do the trick. Any hints on how to achieve a result like that? I'm open to other solutions as well if vellum isn't the right choice for a sim like that.
  2. Houdini Pyro OpenCL Error

    Getting an error when trying to run a pyro sim with openCL: "gasturbulence1: Error: compute_turbulence_cl: Error: smokeobject1 - /obj/geo1/dopnet1/pyrosolver1/gasturbulence1/compute_turbulence_cl: Fields must be matching for OpenCL " Any ideas?
  3. I am trying to recreate this effect, and I can't find any info on how this techniques were implemented… Any help ? Thanks, Diogo
  4. How are you managing your caches? If I have 4-5 sims that builds on top of each other, all of them has a cache, and I change something in the first sim, I need to go and re-cache all the other caches (That maybe are located different places in my network). Are there a way to manage this "chain" of caches, so it's possible to have a better overview of all caches in the sim, and be able to quickly re-cache the sims that need it? What is a good workflow for this?
  5. Hello fellow artists! Example: I have a packed geo, like whale body (in some reason I must leave it packed) also have multiple harpoons (I'm doing simple particle sim and copying harpoon geo on it afterward). Now I'm looking a way how to make harpoons stick to whale's body after collision. It have to follow body movement (It's animated, of course). I guess it somehow has to inherit position, N etc. Not sure even about general workflow. Current step: I'm calculating intersects and can get intersect positions, but what should I do next? Any ideas would be apreciated!
  6. Learn Houdini through Video Tutorials

    Hey, everyone ! I know some of you are having hard times looking for a good Houdini tutorials? Found a really cool website with video tutorials. I like the author of the tutorial, he explains everything very clear. Just in case someone will need video tutorials , here’s the link to check full list of his tutorials: https://www.cgcircuit.com/instructor/tyler.bay Hope it helps! Best, Chris
  7. Fluid Drop Simulation issue

    Hey guys! I'm working on a project using fluid to simulate a drop (something like oil drop) falling and colliding with an object. The thing is that the client ask me if I can separate the drop when colliding with the object in another smaller drop and I don't know how can achieve that, I'm looking for something like have different density in the same fluid object or select some particles inside that can be affected for another force but the fluid is fluid, not particles so I'm lost in that! BTW this is the sim (the second part is the fluid). Cheers! gota v1.mov
  8. How Does Vellum Physical Parameters Works ?

    Hi everyone, I'm trying to simulate paper using vellum and I can't get the friction and drag right. I kind of got the result I wanted, though I still don't understand those values. By "those values", I mean static and dynamic friction and normal and tangent drag. I'm a really visual person and there's no example or graph that show's how this works on the Houdini documentation, so I thought that maybe one of you would be able to explain it to me ? Thank you.
  9. Hi, I'm quite new to Houdini so, I'm probably doing something really wrong. When ever I go into my Dop network for my sim everything freezes up and it takes several minutes for any change to update, it's nearly impossible to work with. I've attached my scene File Thanks a lot Josh ImageBased_Destruction_Cobble_Test_002 .hipnc
  10. RBD Objects Overlapping

    Hello every one, I am using an rbdobject node (not packed) to simulate some RBD interactions between various objects. To duplicate the various unpacked objects, I am using the "Number of Objects" parameter, and a $F expression in the creation frame to multiply them, all within the rbdobject node. Then I added some variance in the positions of the copies by using the $OBJID variable. The problem is that I have some overlapping copies... Is there any way to remove the overlapping copies ? I haven't wrapped my head around accessing rbd unpacked objects within DOPs... Thanks
  11. Hey OdForce! Lately I've been doing weekly quick-tips that I'd like to share with you all. Be sure to follow me on youtube & vimeo for new videos. Also, keep an eye out for my new course - Houdini For the Artist - Modeling I which I'll be finishing up shortly. Cheers,
  12. Character FX TDs - Trixter

    TRIXTER Munich is currently looking to hire experienced Character FX TDs. Booking time: From As soon As Possible. Duration of the contract will depend on the project. Location: Munich Description: Under the supervision of the CG Supervisor, the Creature FX TD is responsible for providing a wide variety of dynamic simulations and rigs for photo-realistic creatures; including clothing, fur, hair, muscle and skin. Responsibilities: · Creation of fur, feathers and grooming for photo-realistic creatures · Develop simulation setups for photo-realistic creatures; including clothing, fur, hair, muscle and skin. · Involvement in the development of departmental tools and techniques · Regularly communicating with Production and Leads regarding schedules and deadlines · To be able to work with the visual effects supervisor, and the lead CG artist to determine the best creative approaches and techniques for all the different steps in a 3D production pipeline. · Be able to deliver work within established project targets and the high quality standards of the company. Requirements: · Minimum 5 years of experience in a CFX/FX role in a VFX studio · Previous experience on CG creature projects · Excellent knowledge of Maya · Excellent knowledge of Houdini · Experience in the following dynamic simulation: cloth, hair/fur, feathers, skin and muscle · Programming experience with Python, PySide, PyQt, VEX · Programming experience with C++ for Maya and Houdini plug-ins, an asset · Knowledge of 3D-related mathematics, an asset · Experience in creating rig simulations · Rigging skills and experience · Self-driven, good communicator, and a great-team player · Excellent organizational and communication skills · Work ethic focused on the dynamism and collaboration · Ability to perform multiple tasks set priorities and problem solving · Good communication, organizational, time management and interpersonal skills. · English language skills If your experience matches above description we are looking forward to hearing from you! Please send your CV and demo reel by email to jobs@trixter.de.
  13. Retime Fluid Mesh

    Hey wizards, So I'm pretty stoked on the new retime sop but I'm having trouble getting it to work on meshes. In the attached image, flipSim_cache is 90frames and in the retime sop I'm trying to extend the length to 175frames. Problem is, I'm able to slow the animation down but it always end at frame 90 without finishing the original animation. If I turn the interpolation on, my mesh is all messed up. Any pointers would be very much appreciated. Thanks!
  14. Hello! So this weekend I cached a FEM simulation and it went swimmingly--sort of. Okay, I didn't do a .sim cache, but a .bgeo.sc cache. The problem is that the file node I have set up in the project to read the cache doesn't read what was written--it keeps recooking all the finite elements, even though it is not hooked up to anything except for the cache directory. (I even tried switching the file cache node I used to write it to "load from disk," and it still wants to recook everything. I pulled the cache into an empty file and it loads beautifully, so I know it actually cached fine. The next step in the project is to pull it in and use it to deform the original hi-res geo. How can I tell the project to stop cooking and just read what it wrote? Thanks for any help, as always-- **Addendum** - creating a whole fresh new file read node worked fine. I guess at some point Houdini nodes get tired and forget where they are? At any rate, I would love to know what I clicked that made it so forgetful, so I know how to fix it when I screw up again. **Addendum to the Addendum** - the new file node worked fine, until I went out of that subnet and back in, and then it started doing the cooking again. So, still not fixed, and the file nodes are still forgetting themselves.
  15. Source RBD objects

    How is it possible to source in RBD objects (hero) into DOP over time?
  16. First dump from a home-brew Grammar system expressed iteratively as an evolving growth system. A decade of hunting down Blackberries to their roots - to remove them from my yard; A month of looking at and sketching Blackberry growth in the wild. A day with Houdini Apprentice, and a single point of geometry to seed the system. Then just turned it on. There's fewer than 100 lines of code, and I'd guess about a dozen substitution rules in the grammar system. Emergence is an effective approach for modelling organic processes. Blackberry_h17.13.hipnc
  17. Hi guys, I'm kinda new to this software and this is my first post, after several days of trying to solve this problem: Am trying to simulation how stellar wind affects the gas clouds in interstellar space. https://www.spacetelescope.org/images/potw1106a/ (reference picture from Hubble) When new stars are born in high density regions, the ignition and radiation of these stars create winds that pushes the dust around them, sculpting away the surrounding molecular cloud. These winds can reveal this hidden star formation process and sometimes accelerate it, when this expansion compress another high density spots, this slowly collapsing cloud will form a new star. These places are also called stellar nurseries. So, i'm trying to visualice is the first parts of this process, the way stellar wind sculpts and reveal the clouds around them. I've modeled a random cloud to represent the very uneven density distribution. Where i'm having problem is in getting this "wind" to affect more the lowest density regions. I tried with a couple of fan forces in oposite directions and kinda worked, but could not get to work a mask using the density field, maybe is posible, but i couldn't do it. Then i tried a gas field wrangle to get a another velocity field "wind", from the origin and multiply it by a factor inverse to the density squared (see screenshot) This also kinda worked, but i get a very voxely looking render (video attached), maybe with a higher resolution and some blurring node somewhere could improve this. I also would like to achieve the effect that the winds is slowly expanding trough space (since the spatial scales here are huge), maybe i could bound it to an expanding sphere? (i dont like that the wind effect is instantaneous in all the scene) maybe some kind of raycast could be an option? i'm open to ideas, coz i don't even know how to begin to google that :/ That's what i've tried so far, would be really happy if someone could share some ideas or resources! Thanks in advance. pd1: another idea i would love to implement is to fake the dust colapse by gravity with some clumping also based on density (i tried with gasshred and gas surface tension with poor results) pd2: Eventually, i would like to get this expansion and subsequent peripheral density increase around to spark the birth of new stars. I don't know if is posible to create fuel from a certain density threshold or something like that. But that's a second post i guess. StarDust_07.hip StellarWind_Advect2_1.mp4
  18. Crowd Sim Popping

    Hi, I've been playing around with the demo crowd sim setup inside Houdini and wanted to setup my own based on this. I used MakeHuman and Mixamo and setup a character with animation. I got all the parts working but for some reason the animation on my character pops like the rig or cache is breaking. I've narrowed it down to being something about the retiming being done in the crowd sim but I have no idea what the actual problem is or how to fix it or even what to search for. Any ideas? Attaching my scene just in case. sim_test_v02.zip
  19. When would you use FEM over Grain? The last couple of weeks I have been working with Grains, and got a good understanding of how it works. It seems that you can do pretty much everything with this tool in case of cloth and simulation of object that will deform. I haven't been using that much time on FEM, and from my perspective it looks like a tool that has a lot of overlaps with the grain tool. It could be nice to get an understanding of where the FEM and Grain tool differs and where to use which, from people that has good experience with both tools.
  20. Hello everybody! I am glad to present you my latest tutorial “Liquid pixels simulation. Houdini tutorial”.
  21. Hi guys! I would like to share here my latest personal project. Everything done in Houdini and Mantra Hope you like it. Youtube Version: Shark_Youtube.mp4
  22. Colored Smoke with CMYK

    Last week a guy asked in the brazilian houdini group, in facebook, how to simulate colored smoke. I believe there are lots of hip files with this kind of effect, but while thinking about it, it came to my mind the possibility of using CMYK instead of RGB, since cmyk is more suitable for mixing colored things other than light. I couldn´t spend more time testing it or improving the file, but it seems to work, so here´s the hip file. colored_smoke_V002.hip
  23. Fast smoke simulation

    Hi there, I am learning about smoke in houdini and I am desperately trying to achieve an effect like this By this I mean a fast paced smoke puff that spreads out wide, like almost in a V shape. However, no matter what I do, my smoke always ends up looking very straigt. I can achieve the fast paced but then it looks even more straight I think. I tried making it faster by chaning the time scale, giving it a high buoyancy lift, using my normals as a velocity volume (in source volume node) and setting the scale of it to very high, setting the temperature scale to a higher values, etc. All these individual things work for the speed, but I keep ending up with quite a straight line, or something that isn't making sense at all. I tried adding turbulance, but this also doesn't help me to achieve that "v shape". I hope someone can explain to me what is going wrong, because I am totally lost.
  24. smaller ripples

    Hi guys, I have a flip simulations where I am dropping a rock in a vase. I would like to keep the velocity of the splash it generates, but I would like to decrease the amplitude of the waves that the flip sim creates. I've tried to play with the velocity smoothing, but it will also decrease my splash highness. any suggestions? maybe it's worth doing it post sim? thanks a lot
  25. destroying animated geo

    hello, i am currently doing some r&d for a bigger project in which i have to destroy certain parts of a transforming building. so i started to animate a building-like shape with a growing collider inside, so I could start researching how to fracture and constraint animated geo and destroy just the parts that really get hit by a collider while the rest follows the animation. it worked out quite good, but now i got to the problem that even if the destroyed pieces are laying on the ground, they still sort of follow the overall animation. I tried to put deforming to 0 in a sop solver inside dops after reaching a certain speed but that didnt really help at all.. can some of you give me any advise? thanks in advance! animFracTest.hip