Jump to content

Search the Community

Showing results for tags 'density'.



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 34 results

  1. axiom with MOP_spread problem

    Im working on a pyro simulation using axiom solver. I have an animated tiger in scene, I then use MOP_Spread to animate the @mops_falloff from head to tail, then I multiply @mops_falloff with @density to have the density source animated. As you can see the density is smoothly transform from 0 to 1, but when I run the simulation with sub step by 2, there's some point the density spawn even though the density source has not yet reach to the point. Is there anyway to fix this matter? Thks in advance. pyro spread.hip 03_Anim_Xich_Ho_intro.fbx density_source.mp4 axiom_solver_problem.mp4
  2. Vary RBD object weights

    Hey Everyone! I'm doing an RBD sim of multiple objects colliding. I am merging them and plugging then into the rbdbulletsolver. Does anyone know how I can modify the weight/density of one of the objects so it reacts differently to the other objects? Thanks so much!!
  3. Few nodes won't work on OpenCL

    Hello, I am trying to work with OpenCL but as soon I enable them on few nodes, like the gas disturb, gas turbulence, it stops working. I just get a mushroom smoke effect. Does openCL not work on these fields? I have attached some screenshots. The first image is without OpenCL, the second one is with smoke disturb disabled and the third image is with openCL enabled on Smoke disturb.
  4. Hi everyone, did a pyro sim along with a collision object. When I up the density from 1 to 4 in the pyro shader, the voxels are getting visible (attached an image to the post showing the issue). Is there any way to prevent that or soften the voxels on the outside in a post process or something? Cheers, Christian
  5. Hello! So I have been Having lots of problems to setup the pyro sim on a large scale. Somehow I cant manage to understand the propper settings. I would love a result similar to this: The size of the my sim is 1:10th of the real size because as I make the sim bigger the problems also get bigger. I guess it has something to do with the source density and the smoke object Take a look on how awful it looks down below (I am quite new to this soft) I am leaving the whole proyect full of notes so you have an easy time helping me Thanks a lot and I am looking forward to learning. cya NaveVolando.rar
  6. Smoke density based on ramp

    Hi everybody, I am new to houdini and i am already scared. I know how to emit pyro from colors by using ramp than a delete node with a $CR < 0.1/.5/.8. on my emitter it work but i want to control the "density" of the emission based on the gray level of my ramp/paint node. Meaning white zone = 100% emission dark zone = 0% thanks you
  7. Hello I am trying to mix/combine the density and colour of two different VDBs into one VDB in Houdini (image 1, file attached). For the most part, this is working as desired but there are two main issues: 1. Pink fuzzy edges around the blue VDB - How do I get nice clean edges where the blue VDB smoothly fades out to transparent? (image 2) 2. Blue VDB does not go all the way to the border of the pink VDB - How do I make sure both VDBs finish on the same outside border? (image 3) I have tried adjusting the voxel size, changing the set up of the VDBs (ie. the exterior/interior band voxels, fill interior) but I can't seem to get it working the way I want. Can anyone please help me? I have only been learning Houdini for just over a month so example files would be helpful. Thank you! Mix VDBs.hip
  8. LYNX | Free VFX Tools

    Hey folks, proud to present LYNX Tools, a collection of production proven open source tools to accelerate your workflows! All mentioned tools are free to download via the links below and are licensed with a full HoudiniFX license. All Houdini Assets have complete Houdini native documentation available. Repository: https://github.com/LucaScheller/VFX-LYNX Lastest stable release: https://github.com/LucaScheller/VFX-LYNX/releases Please give them a test drive, so we can improve them further Roadmap | https://github.com/LucaScheller/VFX-LYNX/projects/1 So far there are three tools: LYNX_force_general | Tweak your sims with this all purpose & intuitive force field. Built to mimic force fields in other DCC applications, but with support for more features and a natural Houdini user experience. https://www.lucascheller.de/vfx/2019/03/24/vfx-lynx-houdini-force-general-asset/ LYNX_fabric | Create fabric/weave patterns with ease. Perfect for creating that holiday sweater you never wanted. https://www.lucascheller.de/vfx/2019/03/16/vfx-lynx-houdini-fabric-asset/ LYNX_velocity | Get control of your velocities via an intuitive UI or groom them for absolute fine tuned control. https://www.lucascheller.de/vfx/2018/11/01/vfx-lynx-houdini-velocity-asset/ More info on my website, including full release logs: https://www.lucascheller.de/blog/ Houdini User Group Munich Presentation: https://vimeo.com/334887452
  9. Hey, total noon here Just started learning houdini recently. Made a candle flame and adjusted it like I wanted it. When I am converting it to VDBs I can't get the density right and thus it looks wrong or is invisible in maya. The file is attached, any help is appreciated CandleJet.hip
  10. Hey guys, I'm making a smoke a sim of a person blowing out smoke (vape smoke) and when the smoke starts to dissipate and get's close to fully disappearing the resize fluid dynamic container just shrinks and clips that area entirely. Looks very jarring and obvious fake. I don't know why this is happening. It still happens when I increase my substeps to 3 so I don't think that's the issue. When it's at substeps 1 - the clipping still occurs but more smoothly (if that matters). I've attached my scene file and a flipbook of the crime. I'd really appreciate any help with this! Smoke_03_ForReddit.hip Pyro Clipping_For Reddit 2.mp4
  11. Pyro showing fuel in render?

    Hey, So i im having this small issue where I think the fuel? is showing in the render and it is ruining my pyro sim to look like a clean flame. I have density turned off, so there is no smoke and temp and heat are the only attributes being used in the material node. I'm assuming fuel is the source of the issue and it is being rendered through heat. Any ideas on how I can remove that small cloudy emission on top of the flame (in the picture below), in the video you can see it in the middle of the flame, you can see it on the 2nd and 3rd one but it doesn't seem to appear on the the black body one (1st one) It seems to only happen when I use the ramp to colour the flame
  12. Recreating an ultracentrifuge

    I'm trying to recreate an ultracentrifuge that seperates high density particles from low density particles. My current setup is two fluids with separate densities being emitted side by side to fill the container. Then once the container is fully filled I start up the "centrifuge", a pop axis force to spin everything at high speeds. The problem is it just acts as a blender and not a separator. I have a little divergence to pump up the fluid in the beginning but then it's removed. The densities are about 400 kg/m3 apart. I've tested fast and slower with different drags and settings but still just blends. Anyone else try something like this? Maybe I'm missing something important (more than likely, ha). Thanks! Update: kind of working now adding some mass, drag, and applying the rotation only to the low density particles. Faking it till it makes it I guess.
  13. Fluid Drop Simulation issue

    Hey guys! I'm working on a project using fluid to simulate a drop (something like oil drop) falling and colliding with an object. The thing is that the client ask me if I can separate the drop when colliding with the object in another smaller drop and I don't know how can achieve that, I'm looking for something like have different density in the same fluid object or select some particles inside that can be affected for another force but the fluid is fluid, not particles so I'm lost in that! BTW this is the sim (the second part is the fluid). Cheers! gota v1.mov
  14. Hi!! I have subdivided the primitives of an icosaedron. What I want is for each primitive, to select a random number of subdivisions (the small black triangles) , extrude them and control their density with an attribute. How can I do that?? POPULATION -HAPPINESS.hipnc
  15. Issue advecting vectorfield

    Hey guys! Trying to figure out the whole custom vectorfield aspect of the pyro solver, but running into some issues.. I created a new vectorfield (Cd) under the smoke object, importing a Cd vectorfield that i want to use in a source volume node (replaced velocity with Cd to Cd as another forum post on here suggested). Then I added a gas advect field microsolver to the advection input of the pyro solver. With the multi checked on the visualization and Cd in for diffuse, I can see that the vectorfield is properly being sourced, but it doesnt advect by the velocity field for some reason, it just sits there. The gasadvectfield node should move the Cd by Vel right? I've found some good forum posts about this here, but for the life of me can't replicate the effect. Any suggestions / advice? Thanks! Cd_advect_v01.hiplc
  16. Hi, I want to render a custom pass for clouds in mantra. The reference jpg shows a custom pass from Maya (density / ambient) and the alpha for the same clouds. In Maya a gradient ramp was used on the incandescence channel. Basically where the clouds are denser should be black and the opposite, for lower density I should have white. Can I replicate that with mantra? I'm using the sky rig tool so everything is calculated at render time. Thank you!
  17. I am doing pcopen in cvex to to render points as volume but for some reason I am not able to scale the density as much as I want. It looks like it is clamping the density values and doesn't allow me to go higher. When I use smaller IFD bounds this problem fixes itself but also it cuts my overall object. Also vex volume procedural doesn't seem to work with new mat context. Thanks for the solutions, Alican
  18. Volume mixing with VolumeVop

    Hello ! I made an explosion and I try to make it loop with Timeshift and volume mix nodes, Sadly I feels its too limited as the fading between the two volumes are quite obvious. Is there a way to mix volumes with a VolumeVOP ? The idea is to add simple 3d noise as the volume fade in and out. Thanks a lots
  19. Advice needed for pyro sim

    Hi Guys, I am currently working on a shot where I need to simulate an object falling slowly through deep water whilst bleeding (The more blood the better). Initially I began with a pretty simple setup, An emissive object, a collision object and a divergence volume which is being used for expansion. The problem I am running into is that I need the smoke to continually expand, whilst becoming more diffused and transparent, but to always remain in the sim. So I have disabled dissipation as I don't want to lose density, but this leaves me with a dense volume which isn't transparent or diffused. I would like the density that is in the sim to have an aged based blurring. I did try to achieve this with a gas dissipate and heat field but this still wasn't right. I have also spent time trying to tweak the pyro shader to achieve the desired effect but I am not having much luck. Below is an example of the look I am trying to achieve. Between 0:21 and 0:34 Any advice will be greatly appreciated. Many thanks, Clive Blood_in_water_odforce.hip
  20. Hi folks, which node can set texel density to UVs? And why are all the polygons are separated in the UVs? I tried to use Fuse UV but that's not solved it. Maybe I missed something I'm newbie to Houdini :]
  21. paint density

    hi guys i use paint node to get particular scatter points for my object but when i fracture it, pieces look so long i guess it is a density problem. i just want irregular pieces but more points in some areas.how can i fix it.please help me... test.hipnc
  22. Change Density of Flames Pyro

    Hi, How can I adjust the density of the flames in a pyro render? Right now, I have smokeless flames, and the flames are not dense enough. You know how you can change the density of the smoke? Cant you do the same thing for the flames? In visualization of the smoke object, I can make the flames appear more dense in the viewport by going to pyro's visualization go to emission then scale it up. You can see the results below. How can I do that in the shader, though? The flames are just to thin and transparent. The only thing I see is the fire intensity scale, but it makes it brighter not more dense. Any suggestions? Thanks
  23. Hello,I have 2 questions about the hair:1. When I paint the density attribute the hair guides are reacting based on the vertices, i.e. when I hit only a vertex guides disappear (or appear). It means that with low polygon count I can't avoid stepped guides boundary. But with more subdivisions it is practically impossible to work due to long cooktime after each brush stroke… How can I deal with the guides between the vertices without increasing subdivision? Attachment below describes it.2. To delete hair guides (for example, for hairline or beardline on the head) I use Length Adjust shelf tool with Target Length value of 0.001 (complete 0 is impossible), but this still leaves hairs roots as dots when rendered. Is there a cleaner way to delete the hair neatly along the boundary?
  24. Volume density from texture?

    Hello magicians, I saw a great image by Lee Griggs the other day and I tried to replicate, here is the original effect He did it with Arnold (i think in maya), by projecting a texture into a volume density, here is some explanation https://support.solidangle.com/pages/viewpage.action?pageId=55710284 I didnt know how to project a texture into density, so I projected a texture, the deleted by color and converted that into vdb > fog, but that way I don't get any depth, any ideas? I've read about a rest field that does something like UV on volumes but cant figure out how Here are my attempts: Hip file attached, Cheers! volnoise3.hip
  25. Pyro Attributes

    Hello! I'm encountering a little problem with Pyro Fx. When I export a geo file from any fire, the attributes of heat, temperature and fuel look good in the viewport but when I render them, I get a particles cube. It seems that those attributes are not exported in my bgeo files (I tried with Vdb files and got the same result). Is it a bug or is there a step that I missed in the export? Thank you!
×