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Found 47 results

  1. Hello! I feel like this has an easy solution that I'm just totally missing, so at the risk of sounding dim: I have some scattered points over some geometry, and I want to use those scattered points to emit/create whitewater. What is the process involved in having points used in the whitewater solver? Thank you!
  2. I am not able to emit fluid from mesh that I imported as ABC from Houdini. Getting this error. I also get the same error when I apply a MEL script that applies shaders randomly. // Error: file: /Applications/Autodesk/maya2016/Maya.app/Contents/scripts/others/dynExecFluidEmitterCommands.mel line 47: Object 'file1_106' not found. Attaching the abc file as well skelly2.abc
  3. Hello all, I've hit a new problem, which is my object will not fill all the way, it stops when the emitter is under water. I've read on here that I could use the expand tool in the populate containers shelf, but when I do this it won't let me select my fluid. I tried another way of adding divergence, but I'm over my head as a new user. Here is a link to my scene file and the abc that goes wth it (attach it to the figure_geo). Dropbox - scene files If someone could please help me figure this out I'll be very grateful, I have a deadline for uni looming over me and I'm incredibly stressed out!
  4. So...I'm trying to create this effect: I've tried what I suppose would be the "standard" method. Create an emitter, add velocity from normals, add some curl noise, add white water, add mist... Unfortunately it doesn't even come close. It seems that there are multiple fluid streams occurring at the same time, with multiple high velocity injections blasting into the main spray. If I attempt anything like this with a fluid sim there is suddenly fluid everywhere, and the injections just add to the overall sim. I'd really appreciate any ideas how I could go about setting up a sim that could get me close. Pyro? Fluid? Smoke? Thanks so much in advance!!
  5. Hello everyone.I am working on a short movie using Houdini at work and the plan is to render the whole thing in a game engine, either Unreal or Unity, I know my way around Houdini Engine, but I cannot for the love of Pete find a way to export Pyro FX and Flip fluids to these engines for render, could anyone tell me if this is possible, and if yes point me to learning ressources on these subjects, many thanks for any responses.Gilles
  6. Hi all ! First Happy new year ! It's First water project I made in Houdini. Simlation and modeling and destruction was done in Houdini. Thx
  7. Hi ODForce! First sim, first post, super newbie... we just started working with houdini at work and we have a whole serie of blood splatters simulations to create. We would like to have them as much art directable as possible, so I am trying to control my flip fluids emission from standard particles. How can I emit from a standard particle system?... what operators or workflow do I need between the two solvers? Currently when I try to "emit particle fluid" from an existing particle system it says no surface detected or something like that. Thanks!
  8. Hello guys, I didn't get any answers from the sidefx forums so I'm trying my luck here. I am simulating urine from a medical cup going into a toilet bowl. Obviously, the water in the bowl is going to be clear, while the urine would be yellow in color. So I will need two separate objects to bring back into Maya for rendering (this is necessary). My current setup is successfully colliding with each other (the urine and toilet water). I am not sure what the correct way to set it up was, but this is currently how it is set up: * Urine fluid particles are sourced from a flip tank sop that's pruned– to match the shape of the cup that's holding the urine. That is then imported into the autodopnetwork through the flipobject sop and put into the first input of the flip solver. * The water in the toilet bowl is sourced slightly differently. For this one I did the same process by making a flip tank, pruned it and then made that a vdb and used the fluid source sop. This one is put into the fourth input of the flip solver. The reason I did this set up was I just could not get them to collide with my previous method. I tried making them both into flipobjects and merged them with mutual collision (i also tried left affects right) but they wouldn't interact. With the current set up, they do. Now I am wondering, how do I isolate the two different fluids so I can export them as separate objects, is it possible? Would appreciate some help, thanks!
  9. Hello, I got a closed water tank which contains the fluid inside. So the initial setup for my shot is working fine where the fluid is inside the tank. I have a RBD simulation for the water tank which starts at frame 200 and I cached out the simulation and reading that in the fluid simulation as a static object with deforming geometry. Till frame 200 the fluid contained inside the tank is working fine but after frame 200 when the tank starts to break 80% of the fluid disappear. How the fluid goes missing when the tank started to deform? Any help will be much appreciated. Thank You!!
  10. I am trying to make a scene where there is a flowing river going under a bridge. I also created a fractured house which will be driven by the flowing river and get crashed into the bridge. The only problem I am facing is that the fluid sim breaking the house even before it get hit by the bridge(which is normal interaction between rbd and fluids). Is there any other possible way in which I can interact both my rbd and fluids in a good way so that it doesn't break before hitting the bridge? Thank You Here is a reference shot what I am trying to achieve
  11. Hello. I just recently graduated from VanArts which is based here in Vancouver. I have completed my demo reel in FX which is to say primarily using Houdini 15.5. I hope you all enjoy watching it as much as I enjoyed creating it. I am attaching the link below. Please let me know of any suggestions, criticisms all is welcome. Thank you. FX DEMO REEL 2016
  12. Don't miss our latest GridMarkets Houdini Artist Feature with FX TD Javier Meroño, who has set himself a challenge: how to create fluid shots without resorting to fluid sims. Find out more about his investigations here.
  13. I just found about this stuff, that was brought at last year´s (2015) SIGGRAPH in Asia and it might be the next "great thing" not just for fluids but for compositing, and many other stuff... I think it´s mighty interesting. http://www.physicsforests.com/
  14. We have a few projects coming in the NY branch and we are looking for freelancers. May also consider candidates outside the country. If you are looking for a permanent position you should also get in touch for a possible future opening. thank you
  15. Hello everyone, I'm attempting to recreate the shapes of large bubbles forming. My initial tests have been involving FLIP fluids, adding surface tension and removing gravity to create a jiggling ball of particles. Once it is meshed, I could then apply a refractive shader to get transparency. See the attached .mp4 for a flipbook of one of my tests for creating a small, single bubble. However, I'm curious as to how other artists might approach this problem. How would you go about creating these large, wobbly shapes so that they act naturally? How would you allow for art direction if you went with a simulation approach? Please share your ideas, I'd be very interested to hear what you think! Thank you! There is a good example of the shape I'm trying to create at 2:55 in the video below, although the whole bubble sequence is quite useful. bubbles_rnd_0708_01.single_bubble.mp4
  16. Hello, I'm new to Houdini. I am trying to get particles to follow a curve and end up filling a bottle but I cannot get the bottle to fill or the curve to work effectively. I've tried a bunch of different things but the closest I've gotten is with these two files. I used an OBJ of a bottle and turned it into a VDB. In the first file (particle_flow_v07) I used a popnet to get particles along with a popcurveforce to flow along a curve into the bottle. It looks like it worked ok but the bottle doesn't fill up all the way. I thought it was because they are particles and not flip particles but was unsure how to convert them to flip particles. In the second file (v13) I tried using a sphere as a flip fluid emitter instead. The particles follow the curve ok, some of them fly off the curve even though I increased the force of it; and the particles that end up in the bottle only fill it to a certain point then they just spill out everywhere. I tried modeling a funnel to get more particles in the bottle but it didnt seem to work. in v13 theres also a torus I was going to try to use as a sink object but I couldnt get it to work correctly. Any help or advice would be very appreciated. EDIT: So I tried a bunch of tests and I still get the strange purple collision box through my ground plane; not to sure what that is; maybe its the particles colliding with the ground plane? The particles flow along the curve beautifully so thank you for the tip about my particle separation. Particles are still leaking though my geometry and I have a bad feeling it's because of the obj I found online but I am still unsure. particle_flow_v13.hipnc Glass Bottle.obj particle_flow_v07.hipnc
  17. Hi, recently I watched this breakdown. I am not sure that I understood how author did collisions with fluids. It seems to me like he generated motion vectors in compositing application (Nuke's vector generator?) and then somehow transferred it to houdini where he generated velocity field based on those vectors? But I don't understand how one can transfer 2D motion data from one camera to 3D. It isn't possible, is it? I'd say that for such collisions proxy geometry must be animated. Like in this video (1:00) Do you have experience with integrating real footage collisions with fluid sims? Are there any workflows that can speed up this process? Thanks, Juraj
  18. So I created some simple geometry in C4D, saved out as alembic and imported into Houdini. I created a very simple viscous fluid but when the particles hit the surface of my geometry they slide all over the place. In the same scene with the same particle sim I created a box inside Houdini, made that a collider, and the particles hit the surface of the box and don't slide, they act like I want with the viscosity settings and all. I'm not sure if I'm missing something with the way I'm importing the alembic or if it's a normals issue, scaling issue, etc. I attached the scene file if anyone would be so kind to take a look. Thanks! alembic_particles.zip
  19. Hi, I have a project where I want to create a realistic ice melting effect. I am quite new to FLIP fluids, however I read a lot and watched some masterclasses about how the solver works in Houdini. But I still struggle at a lot of areas. Reference for the effect: What I have done currently is played around with the viscosity. Basically I took my geometry and created points out of it, then I an SDF volume from the same geometry and passed attributes the values onto points. So, the inner most points would have the lowest value and going to the surface it would reach 0. I fitted those values from a range like 1,000,000 to 0 and then using a geometry vop in the dop context i just subtract some viscosity from the points at each time step. Here are my low resolution tests: Particles: Meshed: https://www.youtube.com/watch?v=IokJPFoNi5w&feature=youtu.be I got a somewhat decent result, however it looks more like ice cream melting than ice. It feels like the melting is not solid enough. The particles are not holding the shape as ice would. That's how far I got for now. I have a few more ideas, though (haven't tried it yet): 1) Instead of using viscosity I was thinking to start with all the points disabled (not solving) and then gradually activate them. 2) I wanted to try out using pressure, like in this example (they are using realflow): http://https://vimeo.com/13599797 but have no idea how to manipulate the pressure field: I was hoping maybe somebody with more experience would put me on a better track and maybe have more ideas or suggestions on what would be the best way to achieve this result. Also, maybe you have some suggestions on the shading part? I have some ideas, but I always tend to take the most complicated approaches I am using H15. Thank you in advance
  20. Hi there. I've been searching for the answer for this for a while and I can't seem to find a concrete answer. Well, as the topic says I have two (or more) flipfluidobjects in a DOP network but I need to be able to: 1. Have them interact with each other 2. Be able to assign different shaders to them. When I merge everything into a single flipfluidobject and surface it, I can't figure out a way to mask one from the other. Sorry if this is a very basic question, but I'm at the end of my rope Obviously new to Houdini.
  21. Hi, I'm trying to simulate 2 fluids that don't mix, but still interact with each other (similar oil and water). The meshing to some extent works by selecting the particles based on the emitter group (stream_source_surface_from_...) and then ensuring that they don't overlap after converting to a VDB with VDB combine. However, it would be nice to also be able to apply things like surface tension on both fluids separately. I tried my luck with the group field of Gas Surface Tension, but somehow I'm not able to put the two fluids in separate groups. I'm also not sure what the correct group name would be. I also tried using two separate FLIP solvers merged with a Collide relationship, but the two fluids don't actually interact. Thanks
  22. Mr. X is looking for talented FX Artists to join our award winning team! We invite you to peruse our reels at https://www.mrxfx.com/work/ We have positions in both Toronto and New York studios. Job Description Work closely with VFX Supervisors and Leads to determine best approach to solve effects challenges and develop final look in shot development Work with other TDs, art directors and designers to create photo-real effects and physically accurate simulations Accurately interpret concept art and design from the Art Department Use and understand 3D / 2D applications such as Houdini, Maya, and Nuke Provide input regarding tools and interfaces to improve throughput Producing a final overall look that far exceeds client expectations. Qualifications At least 2 years of feature film production experience working with Houdini and/or Maya Experience with RealFlow, FumeFX, and Naiad a plus Experience lighting and rendering with Mantra, Renderman, and V-Ray a plus Ability to script in Python and Hscript. C++ and HDK and plus Ability to quickly master proprietary effects tools and pipeline tools Ability to design, self-direct, and organize your work Strong communication skills and must be able to work well within a team Exercise a high level of focus and skill in a fast-paced production environment Ability to perform visual and analytical problem-solving Strong demo reel and/or portfolio in realistic effects animation, lighting, arts or engineering. To apply please visit https://www.mrxfx.com/careers/
  23. Hi, I encountered some issues concerning the otherwise great smoke-fluid-tools. Maybe somebody can help? FIrst off I'm using a "smoke container" and "source from volume" from the shelves. One thing is that in general I like using physically based lighting, so also using area lights with quadratic attenuation (physically correct). The problem is that the (otherwise incredibly good) viewport preview doesn't take the attenuation into account, so everything is completly blown out. Is there a way to fix this? (of course I can decrease the light intensity for preview and then set it up again for rendering, but that's lots of work.. ). The other more important issue happens when writing out the voxels: I'm using the "export file" and "background render" option in the Dop I/O in the smoke import node for this. What happens is that from some frame on the .bgos get saved but don't update anymore correctly. So the smoke just stops moving. Maybe this is a RAM issue, as it happens with quite hires sims? But it's kind of strange that the files get written without complaint, but don't get updated anymore. (At first I thought this was happening only with OpenCL enabled, but it also happened with pure CPU computing..) Well, that's it for now, thanks!
  24. Strongly based on (mighty) Igor Zanic old Naiad test of an helicopter, I worked on this test to get the hang of the new Ocean FX tools in Houdini, as well as testing how to use custom forces to affect FLIPs (to simulate the helicopter blades). Sorry for the somewhat grainy render and some Nuke retiming flicker around. I didn´t have the time to retime and re-render. I think I make up for this with an interesting test. My conclusion so far is that it´s very difficult to use dynamic waves and still keep your main effect strong and controllable because of the amount of interactions going on with the waves. The reason being dynamic waves require a really huge container not to come back too soon and this adds up on the usual problems on any similar scene.
  25. Has anyone else encountered artifacts with the Gas Resize Fluid Dynamic node? I've attached a simple file that shows what I'm talking about. If you dive into the dopnet, view it from the top orthographic view, and play the first 20 frames or so, it's clear that the fluid is developing grid-shaped artifacts that are *larger* than the resolution of the fluid itself. If you enable the timewarp node inside sphere_object1, you'll see that the artifacts still develop, but much more slowly. So it seems to be related to the rate of change of the size of the fluid. artifact.hip