Jump to content

Search the Community

Showing results for tags 'simulation'.



More search options

  • Search By Tags

    Type tags separated by commas.
  • Search By Author

Content Type


Forums

  • General
    • Lounge/General chat
    • Education
    • Jobs
    • Marketplace
  • Houdini
    • General Houdini Questions
    • Effects
    • Modeling
    • Animation & Rigging
    • Lighting & Rendering
    • Compositing
    • Games
    • Tools (HDA's etc.)
  • Coders Corner
    • HDK : Houdini Development Kit
    • Scripting
    • Shaders
  • Art and Challenges
    • Finished Work
    • Work in Progress
    • VFX Challenge
    • Effects Challenge Archive
  • Systems and Other Applications
    • Other 3d Packages
    • Operating Systems
    • Hardware
    • Pipeline
  • od|force
    • Feedback, Suggestions, Bugs

Found 416 results

  1. Hey, First time posting on the forums looking for some help with a simulation I'm running. So I'm trying to create an effect similar to the ref video here: The effect is a macro shot of soap bubbles entering frame and sitting on top of a surface with some slight movement at rest. Again nothing has to move through the top surface. My current Idea and set up is to run a flip sim to get the motion, take points from the sim and pin some vellum sphere objects to some of those points at their center to get the soft bubbles "layer" then do some vdb combining of the vellum objects and the base fluid. Am I going down the right lines or is there a better way to mix flip and vellum together? Any input is very welcome along with any tests for similar problems people have faced. Also If this isn't in the right place let me know to move the thread! Can post my hip up if it helps. Thanks in advance! Media1_ref.mp4
  2. Hi, I would like to replace the particles in my simulation by another geometry. For my fluid simulation I use the off the shelf, Flip fluid from object. I've had a look into the Flip Object and the flipsolver but I'm stuck. Thanks
  3. i try to create this effect with flip simulation but I can't.... pls help me https://www.youtube.com/watch?v=DHRSkRLJpqU
  4. Hi everyone! I am doing a fluid simulation in houdini that I then want to export in blender. I already achieved something, but I think I am in need of a couple of advices and I hope someone can help me here. This is the result so far after I exported all the elements in blender: VA_WaveTest_Houdini_002.mp4 Question1: how do I export whitewater separating spray from the foam and the bubbles? I am exporting whitewater using alembic to blender and it works great... However at the moment it's all in the same file, foam, bubbles and spray. While the former two I think can be rendered together, I would like to have the spray on a separate alembic or even better VDB so I can render it as a volume. How can I do so? Here you can see my current setup... I see that in the whitewater_IMPORT node group houdini extract some volume info from the whitewater particles so I tried to export those as a VDB but once I imported in blender I think that ALL the whitewater has been exported in the VDB not only the spray. I guess I would have to isolate some part of the whitewater based on some attribute, but I am a bit lost here... Can anyone give me a hand please? Question2: Is there a way to automate all the steps of the simulation caching process? So far I've been doing R&D but when the time for the final simulation come I would like to automate a bit the baking process. At the moment I cache in sequence: flip sim, whitewater sim, mesh and then I export the mesh and the white water to VDB. I would like to know if I can create some kind of BATCH of those actions so that I can leave the computer to crunch overnight and it will automatically start the next step after finishing baking the previous one. Thanks everyone for any help in advance!
  5. Ok so i have this Sim i need to do. It is all working fine, excluding the Arms. These things. I tried using a collision above the pens to get the water to split evenly, not in this ripped pattern. However that didnt work as the collision left an inprint in the water. I am sure there is some parameter i can change to get the water to split evenly and not create these arms. But i am kind of hitting a deadend here. Any help would be highly appreciated !
  6. flip simulation collision

    when I simulation fluid in Houdini, some particles just pass through the colled object. what should I do?
  7. Hello everyone! noob needing some guidance from above here haha I'm working on a flip sim, just melting a cube into a viscous liquid. The sim is good enough but I'm having a little bit of trouble with some subtle flickerings along the edge which are driving me crazy haaha was wondering if there's any technique or trick to get rid of them?, the goal is to make the fluid very smooth. Thank you very much in advance! Best! Attaching a video and some screenshot of my meshing setup. Screen Recording 2022-04-27 at 16.08.42.mov
  8. Hi, what would be the best approach to create this type of simulation (machine gun smoke simulation)? Any Ideas, scene file strategies would be very helpful! Video file: M1A1 Abrams Firing From Hull-Down Positions_1.mp4 Here 's a gif preview -
  9. Hey, I'm fighting god to get this forcefield done this weekend but my fire is just being really weird. I'm following a tutorial to a T, but the fire seems to jitter between origin and the point I want it at on random frames. It also just cuts off out of nowhere. Have I done something wrong somewhere? Is there a box not clicked? Please help! File: https://drive.google.com/file/d/1w-h3BKtCa5Qku2WBKVf3cLWXMssW_3-E/view?usp=sharing Tutorial:
  10. Hi all.. I'm trying to find the solution, how to control water (or whitewater) shape behaviour around the floating boat. I would like to obtain shape like in top picture on the left. But my results always looks something like on picture bellow, (very extensive side ripples) which I don't want to. Nobody in tutorials or PRO courses doesn't explain how to control that behaviour, if I don't want leave simulation to work 'naturally'. I think it has something to do with the custom velocity values, but I had no good result with my experiments. I saw some tutorials for Maya's or Max's PhoenixFD, where was really good looking results. So, does anybody know, which parameter, feature or node is responsibile to control that, if I want to avoid natural behaviour and obtain the shape like on top left on the picture? ps: The top picture simulation made somebody in Houdini (all boat floats is 58 km/h) with some personal 'KA_wave' tool, which doesn't exist for commercial use. ..I can pay for explanation or shared example hip file..
  11. Can you simulate Vellum Brush interactions over time? Hi guys, im trying to recreate the cloth simulation from this awesome project ive found on behance: https://www.behance.net/gallery/136351151/RGB. Im mainly focusing on 0:00-0:005s. I thought they first grabbed a single frame from a vellum solver sim and then to get that extra movement at 0:03s they used the vellum brush to "kick" down parts of the cloth. After trying out the vellum brush im now wondering if that tool can only be used to create stills. I can kind of recreate the kicking down movement in real time in the viewport with my mouse but at the end of the day thats just giving me a still. I need a simulation tho... So my question is can i keyframe or animate the interactions im doing with the vellum brush somehow? if so, please explain how i can do that. Other than that if u guys have any other suggestions as to how they achieved that simulation, please feel free to tell me! Thx
  12. I am new to Houdini (swapping from Realflow) and I have been trying to create a fluid simulation using the wave tank but have the water level move downwards over time, I tried to simply animate the "Water Level" value in the wavetank_initial but the simulation does not work as expected. What would be the correct workflow in order to do this successfully? Thanks in advance.
  13. M1 Max Performance

    Hi Everyone, First: I only need advice on M1 Max performance. I know the fact that Custom PC is a cheaper solution (I have one currently). I will travel a lot in the next few months. I want to buy a M1 Max 16'' with: - 10 Core CPU - 32 Core GPU - 32Gb Memory - 1Tb SSD My current PC Specs: - Ryzen 9 12-Core - RTX2070 Super 8Gb - 64Gb Ram - 1Tb Nvme / 1Tb SSD I wonder if 32Gb will be sufficient to run some simulations (Vellum, Fracture and Fluid)? I'm in doubt regarding the 64Gb Upgrade (or not) I know that.. there's never something like ''too much RAM'' But I wonder if someone had already did a try on Houdini simulations on a 32Gb M1 Max 16''? Is it decent? Are you able to work properly? It's already a lot of money, and even if, when you spend 5000$.... 500$ upgrade could appears ''okay'', But I don't want to spend ''too much'' at the end. (I read myself again..Yeah.. 5000$(with taxes) is already .. a sh*t load of cash) I don't work exclusively on Houdini, but also on Unreal, Unity, Substance, Blender. Ps: At the end, this need to be my main (and only) computer Thank you for your time! Take care EDIT: For the same price (~5000$) Do you have some very good (windows) laptop in mind? (at least 64gb RAM and very good GPU // Optimized for VFX)
  14. tyflow-like cloth explosion

    Does anyone have hints on how to achieve a similar effect as shown in this post by tyflow (an fx tool for 3DS max) : I'm so much in love with the effect, but I want to achieve it in Houdini! Thanks in advance for your wise advice! =)
  15. Hi there, I have been putting together a podcast with fellow artist Kofi. Last week I caught up with Arpita Venugopal who's Head of FX at One of Us. She's a great Houdini Artist and manager so I thought her interview might be of interest to people here. There are lots of different artists and filmmakers on the podcast so they might all be of some interest but this one should be really useful for FXTDs whether looking for a job or thinking if moving up to running a team Cheers, Daniel https://www.thevfxartistspodcast.com/how-vfx-changes-your-view-of-the-world-with-arpita-venugopal-head-of-fx-at-one-of-us
  16. Select top layer of simulation

    Hello, i'm currently working on a project where i did a sand simulation. That worked. But now i only want to see the top plane of the simulation, so that i can place it my video footage. The Sand is placed in a box and then a character comes through it and some of the sand goes up. Now i want that at a certain y-value the sand is not visible anymore and i can place it in my footage. I hope someone can help me;)
  17. Dear all, Plz give me some suggestions to do simulation of talcum powder as I shown in attached reference gif. Thanks in advance..
  18. Animating a Spring Constraint

    I'm trying to get these two objects to move towards each other after they hit the ground. Blend solvers are being used to allow the objects to transition between their keyframed positions and dynamic states and I need to add an attractive force which is what the spring constraint is supposed to be for. If I plug it in and doing nothing to it outside of hooking up the constrained object and the goal object it works fine. However, I want to control the timing of it so it can work it into an animation. When I tried to keyframe the spring strength or activation parameters the constraint would stop working or not work properly. Result from keyframing the activation parameter. The objects do not pull towards each other, the constraint just keeps them in place. Node network Does anyone know why this is happening? Thanks in advance!
  19. I need to reuse the constraint polylines from an RBD sim after the simulation is done (to create visible geomerty for rendering) but the only geo I can find is the constraint's initial state and the rbd geometry itself. It doesn't look like the polylines are kept at all. How can I reconstruct the simulated constraint lines between rbd pieces to use downstream in the network?
  20. Hello guys, In a simple RBD simulation, when I replace the "Ground Plane" collision DOP with my Collision-Box, the rigid body objects never stop moving! How can I bring them to stop? (When I use the "Ground Plane" node, everything is ok!). I tried to use the " rbdautofreeze DOP", but it doesn't work. Thanks for helping. RBDs_01.hip
  21. Hello, My aim is to be able to recreate an explosion made of objects (in this case pills), which collide with each other and move away and float without gravity in the opposite direction from the central point of origin "of the explosion. Does anyone have any idea how to recreate this effect? My thought was to simulate an explosion or growth effect and then replace the latter with an instance of objects. Any help would be welcome thank you very much in advance!
  22. Hello guys, As you know, the default attribute value of "Density" in Flip-Fluid is 1000. Now, in a simulation with two amounts of "Densities" (e.g 1000 and 100), what is the best way to speed up the rising speed of low-density fluid particles? I want to force them to reach the fluid surface as fast as possible (maybe something like the buoyancy parameter, in the pyro solver). Thanks for helping.
  23. The gist of the effect I need done is this. I need this Logo to start out fractured into a ton of pieces and off screen in all directions then I need the pieces to kindof suction in towards the screen center where they come together to form the full logo My current workflow is basically run the sim backwards (the logo starts off fully formed and i explode it outwards, then reverse the RBD sim) The problem when I reverse the sim I get a very harsh stop on each piece once the piece gets to its start pose I fix this sort of by running a jiggle or lag CHOP motion effect over the points after i reverse the sim, adding some overshoot to the sim so it overshoots the rest pose and then settles back into the rest pose the issue is now i get intersections with the pieces. Was hoping someone might know how i could maybe run another simulation on top of the reversed sim? Like have it follow the same motion but adjust for self collisions?
  24. Tree Simulation

    Hi! First, I would like to say that I have a very basic knowledge of the program's tools, I have a very superficial knowledge of the whole. Maybe I don't really have the ability to do what I want yet but I decided to ask for help here! My intention is to make a tree simulation using Lsystem and 3 more leaves that I developed, I have some doubts in this whole process. I'll start with the part I got with the help of the forum, I managed to do the trunk simulation with the following formula: After that I developed 3 types of leafs with the following formula: What is my problem: within Lsystem I developed rules that have these leafs in the size, angle and places I want. But when I simulate the trunk they distort and the trunk is no longer stuck in its pin group, besides all the leaves don't turn into a mesh, even using a convert node they "break" when the simulation occurs. So my real problem would be not being able to transform them into solid material and then not being able to use them within Lsystem in the simulation, with their rules. I know that maybe it's very complex to help me with all this but if anyone can give me some light, pass a tutorial that addresses the topic in general I would be very grateful! I'll leave the file here too. planta2.hip
  25. Dop I/O vs Dop Import

    I am working on a pyro sim in which i have cached every frame as a .sim file. These are very large, so ive been researching ways to cache the frames more efficiently. This led me to using the Dop I/O to cache out much smaller .bgeo.sc files. I am aware that this enables me to select which fields i want to omit from the cache, hence the lighter files. The problem im having is that when it comes to rendering (using Redshift fyi), the loaded frame from my .sim looks very different to the loaded frame from my .bgeo.sc, even when i include all the fields from the original DOP network in the cache and it is same size as the equivalent .sim (i presume it contains the same amount of information?) From what i can tell the Dop I/O and the Dop Import are both fetching the same information from the DOP network, so why do they look so different when it comes to render time? Hope all this make sense and i appreciate any responses, cheers!
×