Jump to content

Search the Community

Showing results for tags 'grains'.



More search options

  • Search By Tags

    Type tags separated by commas.
  • Search By Author

Content Type


Forums

  • General
    • Lounge/General chat
    • Education
    • Jobs
  • 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 57 results

  1. Hello, is there any analogue of grains attribute "attractionweight" when using vellum solver? Or maybe some advice to achieve the same result?
  2. Vellum Grains problem

    Hey everyone I have a little problem with vellum I could use some help with. I need have a part of the "subject" bloat up and increase in volume to the point where it pops and liquids come out. Trouble is, I cant really get this to behave properly. Most of the time it will stretch the geo too far and not actually tear, even when the break tolerance is like .01. I don't know if I'm doing something wrong with grains or what but they seem finnicky. Also, is there a way to have an active area for the sim to run, like how in an rbd sim you can isolate out an area? I'm using a really hacky way of separating the active and non-active area with which I'm not too happy with.I'm still relatively new to houdini so I feel like I'm missing something obvious. For reference of the effect I'm going for, look up Thunder from Big trouble in little china. Bloat_building_v020.hiplc
  3. Is it possible to create two way collision between rigid body and grains? I am trying to make a simple example where a sphere is dropped down in a container of grains.
  4. Ground / Terrain Collapse Effect

    Hello all, I am looking at this amazing fx made by Axis for Halo e3 2013. Studying the reference ( the terrain fx ), I thought to approach this using RBD fracture to drive a second sim layer of pop grains (sand). However, I am also thinking maybe I could use vdb+volume vops to mimic the motion. and for the second layer, perhaps using just particles emitting in focus areas. I would appreciate your thoughts on how to approach this. GroundCollapse_Reference.mp4 @MENOZ would love your input if possible.
  5. Resampling Stretched Grain Chain

    Hey Everyone, I've a got a scene where I need to stretch out and resample a cable made out of POP Grains. I've managed to get the stretching part going, but the resampling is causing issues. As you can see when the cable gets stretched the stretched parts essentially becomes really low res, so I need to resample it to keep the deformations smooth. As you may have guessed, a resample node inside a SOP Solver did not work. I tried a few different things, including transferring attributes from the old (lowres) cable to the newly resampled one based on uv's, copying some VEX code from inside the POP Grains node itself into a Point Wrangle to generate the needed attributes, and deleting all attributes/groups, recreating the targetP/weight/stiffness attributes and groups, and then letting the solver take care of the rest. None of these really worked. Does anyone have any suggestions for how to do this? I have included my scene file with and alembic file so you guys have a look if you want. Its not the most elegant or pretty thing (still very much in the early stages) but if you follow the bright red nodes you will get to the SOP Solver where I want to do the resampling. Grain_Resample_Help.hipnc shot_0120_maya_export_v004.abc
  6. POP Grains - Experiments and Issues!

    Hello, I have been experimenting with Grains node and shelf setups as as custom setups. I started with a sphere, then a sand castle and last was a statue. Some results were pleasant then I ran into some issues. Weird and strange behaviors such as floating sand clumps. Mainly it looks like too much force or friction. The problem that the solver feels like it is too sensitive (minor values can change things very quickly). Any pointers or advice is greatly appreciated. Copy_of_SandCastle.mp4 SandCastle_002.mov SandCastle_003.mp4 SandSolver_issue.mp4
  7. Agent interacting with Pop Grains

    Hello everyone, First time poster. Coming from a C4d / Realflow background. I have been able to accomplish what I am trying to do with regular objects as a sphere or a cube lets say. I downloaded a zombie crawl from https://www.mixamo.com/#/?page=1&query=zombie . I imported the fbx into an agent and added an unpack node under the agent as I read this was the only way to be able to get it to react with RBD / Fluids etc. My scene consists of a cube with a transform on it to make it a rectangle which I applied a wet sand preset. The rectangle is above the imported fbx zombie. I have a ground plane. I tried making the zombie a RBD and I also tried making it a deforming object. The goal is to sim to grains with the zombie in place (I removed the $T animation channel). Once the grains seemed to be settled and looking like a nice pile of dirt, I spit out an initial_state.sim file. I added the to my dop network. I then selected the zombie and clicked on Awaken by Geometry. I also turned on Enable auto sleep and Start asleep on the pop solver. I am having several issues. I would like once I have my initial state, for all the particles to be frozen or "asleep" unless the zombie interacts with them. Also I was to be able to control the velocity of how his movements affect the particles collisions... and those particles would in turn AWAKEN more particles etc. I can not get any of those to work. I searched every post on the forum with grains. I learned a few things from Rohan Dalvi's tuts. So I am kinda stuck and hoping someone could help me out. I have attached the latest iteration of where I am currently (stuck). Let me know if you have any questions on my end. I just recently bought indie and redshift and loving it so far. Still wrapping my head around attribute wranglers and vex, but one day at a time. Thanks guys! William grains_zombie_crawl_006.zip
  8. hey chaps i'm trying to create a sim of some chips. I want a big heap of them to fall on top of a burger sim i've done! I've tried a few routes and just wondering what is the best way to go about this. I've attached a scene - its a basic setup of some chips model. I've made them packed and they fall. however they are rock solid and just clearly dont have an air of bendyness to them. what is the best way to go about this? I tried FEM ....making one chip... solid embed... multiple copies then run that. It seems to work in a fashion but soon as i turn up the amount of chips it becomes quite sluggish and also if some interpenetrate then you get wildly exploding meshes. I tried a wire solver but found the wires just seemed to do their own thing and not hold a shape or length. I have got the rbd packed working but of course its just simple shapes and they dont bend. I wondered if it might be possible to create a chip that comprises of maybe 5 simple boxes connected together with constraints? attached a scene file below - theres a fem setup in there and rbd packed.. chips_sim_v003_rbd_for_odforce.hip
  9. Grains Workflow

    Hello I would like to use custom geometry(like little pebble shapes) in a grains sim for visualzation rather than use popsprites or just particles dots. I also would like the grain geo to interact/collide like in a RBD sim, what is the best workflow for doing something like this?
  10. Hey everyone, Been trying to wrap my head around this one for a while but after a few days of being completely stuck it would be amazing to get some help with this point deform problem I'm having. I've got a pretty simple set-up that's using the grain solver for quick softbody deformation, I've got three primitives scattered onto some geo which is then being fed into a dop net for simulations, That part is working well, the only issue I have is when I want to re-attach the original mesh to these objects with a point deform, I've been trying to create a for-each connected primitives for my point deform so the deformed recognises each piece as its own object however i'm getting some strange deformations on my objects when I try to point deform them. Any Ideas?
  11. Hello! I'm using grains to fake cloth and I'm having this weird issue where I'm using a popwrangle to update my targetP (because the constraint points are animated), and it seems to be dragging the target points towards the origin? I've compared my set up to a couple example files and can't quite figure out what's gone wrong. Any help would be appreciated! Example file attached targetPointIssue.hiplc
  12. Hello everyone! I'm just wondering if someone knows how to create that a Particles meets and other particle stick togheter, and if is possible to made that. If there is a particle floating around and get close to an other particle floating around can they stick togheter. or any way that I can aproach that?
  13. Particles

    Hello everyone! I'm just wondering if someone knows how to create that a Particles meets and other particle stick togheter, and if is possible to made that. If there is a particle floating around and get close to an other particle floating around can they stick togheter. or any way that I can aproach that?
  14. I adjust the 'Clumping Weight' which I believe is the 'attraction weight'. However when I look into the geometry spreadsheet nothing is updated in the 'attractionweight' after I adjust it. In my still image I created an attribute called 'attractionweightB' where I added it to the 'Weight'. Yet nothing is updated. You can see a comparison where there is many different values in the attraction weightB seen in the geometry spreed sheet, yet the original attraction weight stays at 1. But even if I were to set it to '0.6' for example. I still don't see that value in the Geometry spreadsheet. Please help.
  15. bacon Grains

    would anyone happen to have the bacon scene for that is shown in the master class at time 41? I want to learn how to emit from pops some geo and still be able to use the point deform,
  16. Hey friends, I'm pretty new to Houdini but I'll try to ask you my question in a hopefully understandable way. Can anyone tell me if my workflow is right or if I go the totally wrong way with my thoughts by challenging the task of placing different objects on a surface. I want to achieve something like macro-shots of a beach/sand. Means I want to model different assets and scatter them on a surface with different rotations and scales. They also should not interact with eachother by obtaining a certain distance to each other. Things I have done so far: - procedually modelled 6 grain-assets (lowpoly, about 3k polys each) - grid displaced in Y-axis with mountain - scattered points on the surface My thought is to scatter 6 different seeds of points to the surface and give them different values of Cd and pscale. After this process I want to merge the points into one "point-container" and scatter instances of the lowpoly meshes at the diferrent color-locations. I heard something about the copy-stamp operations but I also heard that this is way more inefficent by using computer-performance than other solution. As far as I know Houdini offers pretty solid graintools. Is there any way to hook up my own grain-assets in this shelf-tools? I tried it for some while now and didn't achieved a solid workflow. Is it possible to make something like a thin layer of sand on a surface without interacting geometry, because I don't need them to be animated in the full space yet. Thanks, Sebastian
  17. POP Grains Collision Issue

    Hey there, I'm having an issue with my POP grains sim. I'm trying to simulate spaghetti or noodles on a plate which are thrown up into the air as the plate is flipped. I was able to modify a scene file to create the noodles and create collision geometry based off an alembic file I was provided. However I'm having two issues: 1. My grains don't stick to the plate the entire time, some of them go through my collision geo 2. I'm getting some very weird stretching with the grains as the sim progresses. I'm not sure if there is some other collision elements that I am missing or settings on the grain nodes that I need to tweak. I've attached a flip and hip file. Any advice would be greatly appreciated. Thanks! noodles_v01.mp4 noodles_v04.zip
  18. Hey all, I'm banging my head against my desk trying to figure this out....I'm attempting at creating a spaghetti-like simulation where noodles start out on a plate, and then the plate is flipped and throws the spaghetti off the plate. I'm generating some noodle-esque lines using pops and grains but I cannot for the life of me figure out how to get them to not intersect. Am I missing something? I was also hoping to add meatballs to this at some point as well which would be sitting on top of the noodles and then get thrown off the plate as well....would this be accomplished with adding a multi solver to my pop network that combines the popsolver with a bulletsolver? I've heard grains and RBD objects don't play super well together so I'm not sure which is the best approach for something of that nature. Thanks for your time!spaghetti_RD.hipspaghetti_RD.hip
  19. Constraint RBD to Cloth (or Grains)

    Hello guys, How can I attach a rigid body object to a piece of cloth? I'm a bit lost on this. I tried cloth and also pbd with no success, now I have no idea on what i should try. There's a file attached (using grains). It's a starting point if anyone can give it a try. Cheers - Alvaro rbd.to.grains.v1a.hiplc
  20. Granular Sheet - Moving Pin Constraints

    Hey everyone, after unsuccessfully scouring the web and the two big Houdini forums I finally brought myself to asking directly. I'm currently trying to animate a sheet of cloth using a granular sheet since the FEM approach is just excruciatingly slow. I've found three methods for pinning parts of the granular sheet in position (@stuck, @mass = 0, @targetP) but I wasn't able to find a use either of these methods for an animated pin constraint. I'm obviously still not really proficient in Houdini since this problem has me completely stumped. So if any of you lovely people would point me in the right direction, I'd be immensely grateful. Thanks in advance! *edit: After searching some more, I came across this thread: While the file attached to the thread works when I play it, when I try to copy that setup into my scene, it just refuses to work, even though the @targetP gets updated. Obviously, I'm doing something wrong but even comparing the node settings side by side I can't for the life of me figure out what that something is. *edit #2: Okay, I finally figured it out. I didn't realize that the sop solver node is empty by default and you have to create the sop structure to update every frame by yourself. Now that I've figured that out it is perfectly reasonable, I just didn't think of that for quite some time. dia3_dmo_001_010_cgfx_setup_v003_pj_stripped.hip
  21. Field-O-Spheres

    This is the first thing I've done that I'm legitimately proud of. Simple, but a lot of fun! Took inspiration from Brandon Woelfel and a lot of the scenes in Pop's Dinner in Riverdale. Any feedback would be great
  22. Freezing Attributes

    Hi Odforce! Im working on a little project using the object packing technique from Ben Watts Design's tutorial. I've got an attribute VOP using turbulent noise to drive the pscale attribute. Im then reading this into a popnet through a sop solver, but when the particles move they adopt the pscale of the underlying position of the noise. I believe this issue is related to the sop solver reading the new pscale in every frame but im unsure how to essentially freeze this attribute. I want the points to be born, adopt the pscale based on the location it spawns on, then for the pscale attribute to remain frozen for the rest of the simulation, how do i go about setting this up? I have attached the scene file here. CardGrowth.hip
  23. Grains cloth - bend resistance

    Using grains for cloth is extremely fast but since it’s not a fully fledged cloth solver it lacks control for creating realistic cloth sims. There is only really self collision and a basic stretch resistance through explicit constraints (through to avoid stretch you have to put constraint iterations very high..), but it doesn’t seem like there’s any concept of bend resistance in the explicit constraints. Does anyone know of a way of creating bend resistance or faking it somehow?
  24. Sand Simulation

    Hi! I'm a student at NAD in Montreal and I'm trying to learn Houdini. I have a project in which I need to simulate sand on top of a falling rocks RBD simulation, which is on top of a FEM sim. (The FEM is the deforming ground) So I cached every collision objects with the CollisionSource node (with 4 substeps to match de grain solver). Now, if I simulate the sand, it explode on random frames. (see flipbook here: password: sandsim This is my second attempt and it still explode (at fist I used 10 substeps) Does somebody have any ideas on what could be the issue? Thanks MountainGrowth_47.hipnc
  25. Hey magicians, Been fighting with this pile setup for a couple of days, I need to make a candy pile, I'm using grains but when I replace the geo there are some artifacts like the geo is inside the particle and leaves weird holes, anyone knows how this can be fixed? It need to be the more realistic way possible @f1480187 would love to hear your thoughts sensei Thanks pile3.hip
×