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Found 59 results

  1. two objects in a granular solid sim

    I'm trying to set up two pig heads in a grain sim that collide together. an extension of the grainular solid example in Jeff Lait's h15 grains masterclass. in stead of one pig head i want to wire in two. I've set up two pig heads (skipping the bone group part for now) see attached file. Jeff shows how to override the P and v with from an animated version of the geo with a wragle. I've set the dop net up the same way with two sources. however for some reason one of the P values apparently collapses to 0. if i switch the merge order it switches which source goes to 0. see attached file. I'm obviously missing something here. help would be appreciated. twosolidpigs.hiplc
  2. Hi I'm new to Houdini and recently I've been getting into DOPs. I have a question I've been trying different things out in dops to see how they work, been playing around with the "Gas Match Field" node and found that it works quite nicely when both fields you are supplying the node with are from the same object Like on picture 1, both the "myField" field and the "heat" field are part of the same object and the node works just fine But what I can't figure out is how to make the node work when I'm supplying it with fields from different objects. On picture 2 "myField" is part of an empty object and the "heat" field is part of the smoke object, I tried to reference them via their paths like on the picture 2 but unfortunately it doesn't seem to work. Does anyone have any insight into why this may be, I can see how referencing field from different objects can come in handy not just for this scenario.
  3. Hi, Can someone help, and explain why after translating a cube up in sops, on the geometry node to postion a box on top of another box. then making it a RBD object. then simply add a deactivate object from the shelf tools, why my pivot and object change position when I jump into dops. Perhaps Im missing something silly here, anyone help please? thanks in advance.
  4. Hi all, I'm getting strange artifacts rendering a flip simulation with the PBR shader set to glass preset. As you can see there are lots of flickering and some features of the mesh even go in and out. If refractions are turned off the problem disappears, however the desired look is no longer achieved. The problem is not present on other presets such as gold, etc. Im guessing this has something to do with how the particlefluidsurface node meshed the sim, being inconsistent with the inner features or something like that. Is this a known issue or something anyone have come across? Can you think of anything to help me resolve it? Thanks in advance, Glass_Test_s.zip
  5. Hey there, how would you go about changing the animation/simulation state of e.g. a cloth sim? I tried the pin to animation attribute to release the cloth object from the animation; but bringing it back to follow the animation is harder. it just snaps into place when I put the attribute back to 1 in the sop solver (dops). Also does anyone know a way to mix between animations and simulations? Lets say the cloth object is meant to somehow follow the movement of a master object but also should react to some forces. Or in other words: object is moving fast = animation state; object suddenly moves very slow = simulation state; objects moves out of the frame again = smoothly go back to follow an animation. The pin to animation attribute isn't allowing 0.5 values or so.
  6. Hi there, I'm trying to control flip particle count per voxel. The idea is to evaluate particle count per voxel on every step (Gas Particle Count) and then analyze the pcount field.. If pcount > n - delete some of particles (pcount - n) to make n numbers. And if pcount < n - add (n-pcount) particles. Any help is highly appreciated. Thanks,
  7. i have managed to create a network of masked gravity force to drive the RBD packed objects but I'm a little confused about how to proceed further. i need to control the moving pieces of geometry more effectively with further forces as well as create debris from the cracks or where it fractures. any direct help (i have attached an example file) or pointing me towards resources where i can learn further would be cordially appreciated. thank you and best regards fracture.avi fracturingGeoMaskingForce.hipnc

    Hey guys, working on a destruction peice and wanting to take the velocity from my charachter and put it into my bullet sim - So decided to try and use a sop geometry node to bring in the calculated velocity (from a trail and fluid source) - which is working perfect. But my sop force doesnt update each frame, its static - ive tried changing the expression from $T to $F and other things, not sure if its a limitation or if im doing something wrong? i will attatch a file but will be missing the geo but atleast you guys can see the setup Any help would be great! Thanks Destruction_v3_t2.hip
  9. I have three individual components to this briefcase, the body, the handle rings and the handle, the body is a static objects and the other two are RBD packed objects, all concave. I am trying to get the handle to hang from the suitcase naturally but they are falling through each other, there is a slight reaction but i cant get them to completely react to each other. I have attached a zip of the three .obj files and the .hip file if anybody could have a look. Any help would be really appreciated ! Thanks! Assets.zip
  10. I have a load of RBD packed objects smashing on a Ground Plane, they're all intersecting by a consistent distance through the Ground Plane, the RBD packed objects are all convex hull rather than concave although changing between the two doesn't seem to make a difference. I've tried replacing the Ground Plane with a static box and trying different geo representations on it but that doesn't seem to work either. Any suggestions on how to fix this would be really appreciated! Thanks
  11. Zero gravity FLIP Sim

    Basically I have a 'liquid metal sphere' that floats up in zero gravity and starts to peel off using a flip solver and reveals the solid metal sphere underneath as everything peels away with a paint like viscosity. I have it all working EXCEPT for when the FLIP sphere and collider move upwards (because of the animation i want it to look like zero gravity) it leaves a trail behind it kinda like where it starts the sim, ' I want to have it all move upowards and then the gravity starts to peel off the 'paint' from the collider sphere Thanks for any suggestions also attached an example file ZeroG_test.hiplc
  12. I have two separate stacks of geo made using copySOP's, i am trying to get them to interact with each other. They do interact with each other but the constrains only effect one model, i can switch them in the merge but its only ever one that holds together, the other falls apart instantly no matter what the glue strength is. Ive put photos below and attached the scene file with the model that needs referencing in. New to Houdini so any help or advise would be greatly appreciated! Thanks PlateSimulationTest001.hipnc plate.obj
  13. I Have stacks of plates and bowls that i made with a copy node on one original model of each type of plate or bowl rather than importing each model multiple times. I want each object to be able to fall and smash independently which i am struggling to work out. When i make the stack a RBD Glued Object it either all moves and smashes the exact same way like they are being read as one whole piece rather than individual plates/bowls or they move individually but the glue errors saying "making objects from different solvers mutual affectors" so they cant smash. Sorry if this is a basic question i am new to Houdini, any help would be greatly appreciated!
  14. RBS SIM

    Hi ,i use Houdini apprentice 15.5 for 3 months now and i have a problem with the RBD collision.In fact, i'm doing and exercice and the goal of the exercice is to have realistic mouvement when the tube push and object on the table. But the collision of the RBD Objects with the ground is not realistic. The thing is watch tutorials and i reproduce in an empty scene the tuto and it works fine with a simple object like a table and a cube, i mean when the cube is put onto the table the cube does not pass through the table. But in the scene you see bellow everything was working fine until I apply the glue node onto the bowl. After that the bowl the dinner plate and the waterglas pass through the table and it is the first issue i have.Secondly when the objects fall onto the ground the collision is not realistic.I need some one help to fix this problems.Thanks you
  15. Running a fluid sim over geometry

    Hello! I was wondering if anyone knows a way to run a flip simulation over specific geometry. The closest visual reference I can think of would be the workflow from Moana. Would you have to turn the geometry in to a fluid object, or is there some way to have the simulation run on top of the geometry?
  16. Cloth sim for sails

    Hey guys, I'm struggling with the fem solver. Basically I would like to create a realistic looking cloth sim for the sails of a ship. Unfortunately I just can't get it to look right. The wind force deforms the object like animated noise insteat of adding variable velocity. I fit01ed nearly every parameter on the wind force or uniform force but it keeps looking like jiggly gum, not like cloth floating in the air. Can anyone show me an easy example on how to achieve something like this? https://vimeo.com/136480165 [vimeo.com]this is how my gum looks like: https://vimeo.com/197677800 [vimeo.com]Thanks!
  17. I want to make a scene that bullet pass through glasses(with fracture), fluid sims and other objects. but, when I make sphere to bullet size, It can't pass through and just bounced off. 1. How can I fix it ? 2. and wanna make it slow which node can I use for it ?? sorry for my poor English and will be pleasure if you help me Thx for read.
  18. particles path circle

    Hi guys! I've made a sim with particles but I would like to keep them rotate in circle for some seconds and then use their inherit velocity. how i can keep them rotating? i've been trying to add angular velocity with cos ($T * 180) ty = sin ($T * 180) this expression, but doesnt seem to work. any suggestions? thanks!
  19. Guys anybody know how to use distribute shelf tool if I have custom dopnetwork inside sop ?
  20. FLIP Cache - Best Workflow

    Hey guys, I assume that the best workflow could be: 1st - Write the particles simulation to disk 2nd - Read the simulation files to generate the mesh (+ cache the geo file) Now, what is the best way to save the particles simulation? Should I do it inside the "particle_fluid" node using a "ROP Output Driver" or a "Flie" node? Should it be connected to the "import_particle" node? Something like this: and how should I read those particle files back? Please let me know if there's a better workflow on it. Thank you, Alvaro
  21. I'm posting this on behalf of Benuts, a VFX company based in La Hulpe, Belgium. We are looking for an experienced artist to help on water/ocean simulation and shading. We're looking for someone with a lot of experience on that specific topic to help finalise shots for an ad, with opening sea - Moses type effect. More information will be provided after contact. If you are interested, please e-mail Alexandra Meese : alex@benuts.be
  22. Hello, I'm trying to create a looping animation of water spiling on the ground, so that it repeats itself every 60 frames , but im stuck at the part that where I need to blendshape the last frame and the first frame since I can't find anyway for the points to be blend shaped to their nearest relative point. waterfallloop.hip
  23. Hi all, I've been using the crowd shelf tools this week, trying to get to know them. The example files are super helpful, and have taught me a lot, but I'm getting slightly stuck on one seemingly simple thing. Controlling the initial position of the agents. For example, I have around 10 agents, walking, following a circular path. However I cannot figure out how to define the starting positions of the agents to be along that circle (so that they are all walking around it from F1). I can only seem to be able to randomly populate a surface, or set the population to 'formation', which allows me to do a straight line, but not a curved one. Both of these are v useful, but is there a way to set a custom starting state for agents (i.e placed along a curve)? Basically I want to set up agents walking around a circular pool. Any tips much appreciated. Thanks.
  24. My Latest Houdini works

    Hello Guys Im Ahmed Saady - Houdini FX Artist based in Iraq now i would like to share with you my latest houdini projects i have done and i hope you like them Also i'm available for freelance remotely work or full time position ahmedstudios@gmail.com Copa America Identity 2016 - beinsports Copa America - mainstudio 2016 Building Destruction - R&D All the information regarding of the houdini work is under each video description Thank you!
  25. another pyro question

    Can someone tell me why often in time people will like to separate out density, temp, vel and merge it back in the smoke object in pyro ( under the initial data as: density SOP path, temp SOP path...ect) instead of that, we can put multiple source volume node to input different channel as well. What is the main different here? All I know is putting those SOP path makes it last longer in the sim, thinking like as if you want to have a shape of a box being evaporate then we will use that and if we are using any of the initial data we will most likely not wanting to put down the Source volume node where this is constantly pumping stuff into the sim. In addition, to do any of explosion sim, is the best not to put fuel data as any initial SOP path since those will stay quiet a while if you are sourcing the fuel on your Source Volume already. In render you will have a constant light area where is being burn even your explosion has already occured and about to finish. Please correct me if im wrong.