Jump to content

Search the Community

Showing results for tags 'particles'.

More search options

  • Search By Tags

    Type tags separated by commas.
  • Search By Author

Content Type


  • 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 327 results

  1. what is a pscale attribute in houdini and how can we use it?
  2. How to delete dynamic points by group

    Hello, I made a rigid body simulation where I have different kind of pieces, like pavement, road etc. I grouped them in a group called "group1" How can I write this in vex in pointwrangle? Take the group1 and if the points in group1 are under -1 in @P.y then delete them. Thank you for your help
  3. Packed RBD from Pop Sim

    Happy Friday, Trying to wrap my head around constraining or copying packed rbd's to particles that are moving along a surface. Attached is my test scene please help if you have time! Thanks, particleRbdTest_01.hip
  4. Hi, I need help dealing with a personal project of mine, witch after fiddling with different techniques, approaches and reading whatever I could get my hands on, can't for the life of me figure out how to tackle! How can I attract particles to a geometry that is being revealed / generated by volume vop noises? Like those particles are flocking together to fill / reveal the geometry? I have seen tutorials of the opposite effect, where particles are being generated by such a map, like object disintegration into thin air - but how can I achieve the opposite result though? Thank you for your time and patience, O.
  5. Flip Sphere Motions

    Hey there, I'm trying to replicate this setup: Liquid Sphere Based on my scene, I have a sphere and the particles are generated from it with iso offset and particles from volume. Within FLIP, I tried to control the velocity with pop forces (POP force, pop attractor and pop axis force) and got somewhat of a swirly motion but the in the reference video, towards the end you can see the fluid is ground around a torus like motion and the shape as well Any pointers on achieving this? HIP file attached included. Thanks! SH02_Water_v02.hip
  6. Frozen Particles

    Hi! I have a rookie problem. Let's see if you can help me solve it. When smoke emission occurs, some advected particles remain frozen when they reach a certain point. Increase the size of the gas container in case they collide with it and slow down, but it does not appear to have been repaired. If anyone has any idea. Attached photo that points to some of these frozen particles. and the hip file. Greetings and thanks for your time. shockwave_CACH.hiplc
  7. Plane Smoke Trail

    Hey guys, Trying to do a smoke trail simulation similar of a jet stream. I've attached a sample hip file below of my current setup. My plane is static and the camera is animated. I've isolated the engines and use it to do a particle simulation where the particles are being blown away with some minor noise and each particle is given a lifespan so it dies and doesn't stay too long. Originally, the particles are being turned into density and be used in DOP with smoke solver for simulation (add disspate, turbulence and disturbance) to get the look of smoke trail but the results isn't really working and not what I'm looking for. I then tried to use the particles as density and just piped into cloud noise to randomize the density so it looks okay-ish but my question is it possible to get a fairly decent looking smoke trail with my setup or is my setup direction wrong? Thanks Sc01_SmokeTrail_v01.mp4 AirPlane.hip
  8. Hey, i am fairly new to houdini and especially to redshift. I have a setup with particles and want some particles to be emitted by a specific distance. I use the particle color as base color and want my attribute to drive the emission strength. If i use mantra everything works fine. Couldnt find any solution. Cheers and thanks, dom
  9. Hi!!, I'm new at Houdini and I'm trying to get this kind of effect Following this tutorial I managed to make a smoke ring https://qiita.com/r-ngtm/items/c5483f1f4700359e0540 how can I combine it with a dop network to fill it with particles? if there is any other way to do it or if you can give me some advice I thank you sorry for my ignorance Thanks! Thanks!
  10. Hello, I'm currently pulling to hair out trying to figure this issue out but what I had a problem with is assigning a Redshift material to particles in my scene... So I have set up a particle dust burst based of an Entagma tutorial and now that I have one I need to create some duplicates of that burst. I have simplified the hip file attached but my little animation has three dust bursts obj merged together so that I can then feed them into a popnet with a vortex so they all swirl up together after they have done their little burst thing. I got that all working so far but when I go to attached RS materials to each separate burst I can't do it. I can assign a material at the obj level and it works fine, the colour changes for all of them *hurray!* but I need each dust burst within the obj geo node to have a different colour. Soooo I dive inside add a material node but the particles render white and seemingly just fail to see the material node. I have tried adding group assignments to the tree above the mat node and then using them to drive the mat assignment but it doesn't work. I've tried attribute create and attribute promote and they don't seem to help. So it seems that I can only assign a material at the top obj level and not within a geo node, but that has to be a bug right ? or what am i doing wrong? I hope I am explaining that alright and I appreciate the help in advance ! Dust_Material_Problem_v001.hip
  11. Here is a small test setup I've made. It is advecting particles along a curve, driven by a velocity field. I added another velocity field pushing the particles back towards the centre of the curve and blended the two. This is done by deriving a new field, based on a volume gradient and multiplying the volume gradient by the volume sample and negating it. So far, I haven't tested it much, but it seems like it is working, but the settings will certainly need some tweaking. As in Houdini, there are very often multiple solutions to the same problem, I was wondering if there was a different way of achieving this...how would you do it or improve it? advectPush.hipnc
  12. Need some help with RBD Packed Object

    Friends, I cry for help. For some completely incomprehensible reason, the RBD Packed Object node in the Dop Network cannot receive data from geometry packed with Assemble. The SOP Path is spelled correctly, but no matter what I do, the objects do not appear, and an error in RigidBodySolver writes: “bulletrbdsolver: Warning: rbdpackedobject1 - / obj / particles / debris_physix / rigidbodysolver1 / bulletrbdsolver: Geometry solver ". If in Assemble to disable the Create Name Attribute, the error changes to: "Warning: rbdpackedobject1 - / obj / particles / debris_physix / rigidbodysolver1 / bulletrbdsolver: Convex hunt does not have any points." Obviously some kind of packaging problem, but how to solve it - I can’t put my mind to it. I checked the official Houdini help, but did not find any special RBD Packed Object requirements for the objects. Someone wrote that he had the same problem solved by turning on the Assemble node, but in this case this node is already working ... idol1.hip axe.obj cross.obj
  13. I'm looking to find a way to make a FLIP fluid sim move particles, which would themselves be used to instance underwater particulate matter or bubbles. All of my Googling turns up ways to make POPs influence FLIPs, but I'm unable to find this, and I'm sure it's depressingly easy. The scene is a pre-animated character diving into water. To get the bubbles as he dives it looks like the best bet will be to emit particles with instanced geo bubbles (correct? No matter how splashy I make the sim, I'm not getting any bubbles happening from the dive itself). Thanks for any help!
  14. Fragrance FX spot

    I'd like to share a project I have been on for the last 3 weeks as the sole creator. All CG work was done in Houdini, Redshift, and Nuke. Some minor work was also done in PS and AE. Shoutout to the Gridmarkets team for the support and helping me meet this tight deadline! Feedback/criticism is welcome. https://vimeo.com/346944545
  15. Houdini pyro particles explosion

    hey all, I have two questions: 1.) How to add smoke and fire to the particles, inside in the geo node? 2.) How to put the particles together, like trails...? I am very confused.. explosion_2.hipnc
  16. Disable (some) FLIP Particles

    Hey guys, Is there a simple way to disable some particles from the simulation like i'd do with RBD? I have a set of particles inside a group and I need them to be stopped at same position but still interacting with the other particles. Does it makes sense? The group is animated I tried setting v=0 but it doesnt work as expected. I did another trick inside a sop solver to get the position from the previews frame so it stays static but then I cant use the resample. Im just wondering if theres a a simple way like like an attribute the would make them sleep. Cheers, Alvaro
  17. Falling Pixel Sort Effect

    Hello, I've been learning Houdini for a couple of weeks now and I'm trying to learn about particles more at the moment. I'm currently trying to create a grid of falling particles that look like a pixel sorting effect. (please see attached images and video link). My thought process has been that I need to create a grid to emit the particles and then attached trials that have a colour gradient to the trials with a falloff. I want the particle trails die out at different times and for the trials them selves to slowly fade away much like the trail of a shooting star or a light trail (hopefully the below examples clarify what I'm trying to say). I've been trying to figure this out and I've looked around the forum but can't find an example. So far all I can get is my particles to fall the way I want with trails that have the colour gradient connected but that's all. Can anyone suggest/show me a way to create the look i'm after? I realise this might be a really rookie thing to do but from my own research I'm currently lost and need some hel Thanks in Advance! Current Scene File: Particles_Field_04.hip Examples: https://www.shutterstock.com/video/clip-1008242815-particles-glitter-rain-awards-abstract-background-loop
  18. I am creating a carpet bombing simulation based upon the beach napalm scene in Apocalypse now. I am setting up sources for pyro and particles and using a POP network to simulate the white phosphorous fuse and white smoke as the initial layer of the effect but I have run into a hurdle with the impulse activation. I have created spheres with animated noise and copied to points along a line. What i want is to cascade the activation of each sphere along the line as though the bombs are hitting the ground at different times. I originally thought of animating a separate sphere along the line, applying a color value of 1 and using attribute transfer to the source points which have a colour value of 0 and then setting the impulseactiveate value (sic mispelt but correct as per houdini tooltip) via a POP wrangle in line after the POP source referencing the Cd.x of the source points but this did not seem to work. @impulseactivate = @Cd.x; Maybe i have made an error as my vex knowledge and POPs knowledge is as a student very new. The only other method i can think of is to create a group for each sphere and then run a separate POP network for each sphere and keyframe the activation. This is very time consuming and I was wondering if someone would be kind enough to offer some advice on how to achieve what I need.
  19. Particles will bounce off a collision object, and I can influence that using the collider's Bounce parameter. Great. However, if I change my particles to grains, they will not bounce anymore, but slide. No matter what I do and this goes for pop grains as well as for Vellum grains. Settting ispbd to 0 is not a real solution, as this means I am not using PBD/Grains, anymore. Any idea? Here's a very simple test scene, using a pighead. Just activate/deactivate the POP Grains node in DOPs. collision_grains.hipnc
  20. Smoke follow (fast) animated curve

    Hey Everyone, i'm hoping someone could help me with this problem. In a nutshell, i need to move smoke down an animated path, so that it sticks really tightly to the paths animation, but with all the dynamism a smoke sim brings to the table, i.e. nice peeling away around all the edges etc - I have a fairly fast moving alembic curve - cached out with 10 substeps. (may not be needed but there if i do) - I am using pops with curve force to fire particles down the path, so they follow the curve closely. - Then im using the particles to source density, and also adding their velocity into the sim so that it makes the smoke move along the curve. - Im using a high dissipation value so that i can tighten up the expansion so you can really get a sense of where the curve is / maintain the shape. My issues lie generally in 2 places: 1. Where the animated curve is moving the most - the smoke / velocities struggle to catch up and i end up with a hard edge. 2. Where the curve is tangentially facing inwards in relation to the curve, the velocities 'add' the other way, also creating a hard edge. To try and illustrate what im after - if i could animate a regular smoke sim down a straight path and then warp it into an animated spline shape / spline wrap effect, this would be the best way to achieve it, but im really not sure if is possible - hence this approach. I have already tried upping substeps - but it didnt make any difference. My gut feeling is that the problem lies within how i am sourcing the velocity. I will point out that i am very much in my houdini infancy, so my ability to problem solve isn't great (yet!) Has anyone worked on a similar effect before, or does anyone have any tips/tricks/tuts on how to achieve what im after? Any/All help very much appreciated! Cheers, C SmokeAlongCurve.mp4
  21. Modelling Zen Stone Garden

    Hi there, I am a new user trying to get into the modelling side of Houdini after trying some simulation, and am currently working on a japanese stone/zen garden based on this image. I've found some great examples on how to create the stones (not worried about moss yet), but I was wondering if anyone out there had any idea how to create the combed patterns around the stones. I just finished doing some work with the ripple solver, but thats too realistic in this case. Ideally it would be something more simple involving grains or particles with instanced geomettry building up more based on a simple black and white image that i'd make in illustrator. Apologies if this is too simple a question, any help is very much appreciated. Thanks, H
  22. Hi, In my popnet, I want that, a new particle is born only if there are no particles in the scene. That is, suppose a single particle is born and dies after, say some random frame, only then a new particle is born. No new particle can be born even if a single particle is alive. How can I do that? Please help Thanks @Alain2131 : Sorry to tag you here, I just wanted some more help. Please let me know if tagging is not permitted or if you are bothered by it, I wont tag you again.
  23. I'm in the middle of creating Whitewater particles for my waterfall sim and after caching out the particles and converting it into a volume it looks extremely low res considering there is over 300,000 particles and 8 million Voxels. Not sure what i'm missing but any help would be greatly appreciated. Thanks in advanced.
  24. Hello, I have an object what I broke with an rbdmaterial fracture then I feed the points into a popnet and add some stuff like wind to move the points. My question is: How can I reset or rebuild or move back the points into their original place and shape like a fast rewind or something. Thank you
  25. Hello, I'm trying to create an effect very similar to the one in the reference video, where particles move through this channel and creep over this bubble. I tried different approaches like vellum grains, regular particles and came closest with the lava shelf tool. But then the individual particles are not touching the surface of the bubble and the overall movement of the particles looks too much like a fluid. I actually want the distance between the particles to stay constant. I think some PBD approach would work best, but can't quite figure it out. Any ideas? Thanks in advance. J NanoParticleEffect.mp4 190524_NanoParticles.hiplc