Jump to content

Search the Community

Showing results for tags 'Volume'.



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 160 results

  1. Finding the Min/Max values in a field?

    I am trying to figure out how to get the converse of a field, mathematically. I am attempting to blur a Cd field in using a Gas Blur microsolver. I have some mixed results, but I want to get some finer control over the radius, namely that I want it to blur more as it slows down. I have used the gas analysis microsolver to get the speed field by taking the length of the velocity, but I can't figure out how to get larger values to be in the lower speed areas. Obviously I would love to use a fit to invert the values, but I am struggling with an elegant way to get the minimum and maximum values for a given field. I could easily just do a loop in a wrangle and get the min/max values that way, but that is going to be extremely slow as this is a very large, dense simulation. Is there a simple way I can get the min/max values in a field so I can use fit(@speed, min, max, max, min) in a Gas Field Wrangle node to get the converse of my field?
  2. is SDF and VDB are same...? if not what is the difference between them?
  3. Hey! I don't really know how to properly describe my problem. I have created a cloud vdb from polygon geometry. Everything works and looks fine but when I imported it into c4d for rendering I noticed I only got a "real" volume export in some areas. I tried to export and re-import my vdb in houdini, it looks perfectly fine. But as soon as I create a Points from Volume sop I get the same issue again. It seems like there are only certain areas where "real" volume is created. I have no idea why this is happening and need a cloud effect for a project asap. Would really appreciate ANY help.
  4. contrail deformation by spline

    Hey guys, I'm trying to deform a volume "contrail" by a spline with direct projection without the use of converting to points and back. I've tested this method on points and it seems to work, but am unable to get it working on volumes without major stepping. It relatively follows my curve, but I can't seem to figure out where the stepping is coming from - it works perfectly with points and conserves it's thickness, so I'm pretty stumped. I attached the project file and few screen grabs. Let me know if anyone has any ideas volumedeform_v03.hipnc
  5. Hey, Houdini has a node called bake volume. It works really well, but it only lets you bake lighting from the built in point light. Is it possible to bake the lighting from my scene lights? Thanks
  6. Hi there, I have a scene that has some noisy ground fog that helps establish the atmosphere of the scene. I am working with a single frame of vdb that was created with some volume noise. It's simple but it works great for stills! I am trying to come up with a good way of advecting it, or at least applying some form of subtle animation that will make it appear more dynamic in motion. It's fog, so it doesn't need to be anything too crazy. Curious what your solutions would be to this problem! Cheers
  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. Hello guys! Can I ask U question, Im very new in houdini. Can u help me please? Im trying to render short video of volume (smoke) in matra, but I really do not know how to set the mantra settings, because one frame is mantra creating for 43 minutes, which is rediculously long time for 250 frames. can U help me, with settings? I already increased the Volume step size, but thats all what I did, (I read somewhere its helpfull) is there any other way, how to make render time (per frame) shorter? Thanks a lot for any advices! Im looking forward to your re´s! By! advice.hip
  9. 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://trello.com/b/f8Pgip7s/lynxpipeline 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
  10. Hi; How could I apply velocity force to an ocean fluid, using an animated geometry? (I think I should use volume, but I don't know how). Thanks. OceanApplyForce_01.hip
  11. Hello, I am curious if it is possible to illuminate a volume with the light emitted from the emissive channel of a redshift material. I can't seem to find anything regarding "volume contribution" within the materials and there doesn't seem to be much documentation on the subject. For example, embers emitted from a flame should illuminate the rising smoke. Thanks! ian
  12. Hello to all people :)! I’m trying to do a few days, a whitewater that surrounds my boats, creating the tip of a wave at the front of the boat, a little like this example ... https://forums.odforce.net/topic/28940-flat-tank/?tab=comments#comment-164200 or that one (Really a defined shape of the whitewater fallowing the boat from the front to the back.The problem, here ... I can not see why the whitewater does not seem to be done and do not keep the shape of the same smaller boats ...) I would also like to know ... how to bake my simulations in order to have an ocean that included my simulations of my boats, with also my whitewater :)? Thank you in advance for your help :)!! (P.S, here is my scene) Boat_Breack_waves_V010.hip
  13. Hi, A simple question but I can't seem to get the answer. I need to convert a sphere primitive to a volume, when I do this with a VDBfromPoly instead of the VDB showing up as a perfect sphere I get this low res sphere similar to what you would get with a low frequency poly sphere (see screenshot) Is there something to tweak to get a perfect sphere, or is there a better way to to convert from a primitive straight to a volume? P.S. The reason I need to do this is because Im copying a few hundred thousand spheres to points and if I try to do this with poly spheres houdini crashes always.. only way I seem to be able to do it is by keeping the original sphere a primitive. Thanks!
  14. Hello, Here is short video showing how volumes can be used to shade and texture semi-translucent organic things. Volumes For Organic Assets This approach allows to achieve close-up realistic organic look for semi-transclucent assets where SSS or colored refraction is not enough. An object with UV's is converted to signed distance volume with UVW grid. Then volume is used to set density and perform uv lookup in rendering. This way density can be adjusted by depth. I.e. not so dense near the surface and very dense at the core. Or not very dense, then dense patch like island of fat, then not dense again. UVW grid is used to texture volume. Different textures can be used at different depth. This approach allows very flexible yet powerful way to place any texture at given depth. Texture X at depth Y. I.e. big veins are 5mm under the surface. This approach is best for close up organic hero renders where SSS or refraction are not looking good enough. Attaching example file volumetric_textures_example.hip
  15. Volumetric Temporal Deflicker 2.1

    Digital asset download at Orbolt! Enjoy https://www.orbolt.com/asset/RodTD::Rod_vdb_averaging
  16. Hello ! In order to setup my different Disturbances and Turbulences inside of a smoke simulation, I'd like to know what range of velocity I'm dealing with. How would you guys do that ? If you have the proper method to do that just ignore what's under. The sim is already cached (density, vel, rest, rest2). What I'm doing for now : When looking at the node info there is vel.x, vel.y and vel.z. I don't understand why but I've read that these are scalar values and has to do with how Houdini works so why not. I don't know how to inspect this volume further than that since it's a volume the Geometry Spreadsheet doesn't display anything. And when I apply a VolumeSlice I get 10 different vel attributes per point. vel[4] matches vel[7], vel[5] matches vel[8] and vel[6] matches vel[9]. But not the rest of the values. This is very confusing to me.
  17. advect by volumes node limitation

    Hi, I am trying to understand advectByVolumes node. Basically I create custom vel field and animate density by advection. When increasing timestep, density moves more, but there looks a certain distance limitation, and density does not move further anymore. I wonder what's a logic and a solution for that, instead of using sop-solver, in order to continue to proceed density animation. advectTest.hip
  18. post process volumes

    Hey I'm looking into some volume post processing, I need to be very art directable on a volume after the sim so basically what I need to do is define areas where I need to increase density for instance, or decrease it. which is the best way?
  19. Starcraft Growth Project

    Hey there! Trying to be more active. Here's a WIP of a project I did for Peter Claes's Houdini class. Such a cool technique to play around with. Struggled a ton, and have lot of extra RnD elements that got gutted haha. But I learned a lot. Have to Re-Render, have some slime / rivulets for the eggs in the next render, which I have been struggling with. Initially was flip but switched to something simpler and less heavy.. Had issues transferring V for motion blur due to changing pt numbers but I'm sure someone probably could figure it out! Wanted to add one of the eggs exploding. but stretched thin on time. Will do another rnd for it. Will re-render without motion blur I think. Someone had idea of adding veins, like a neural network that activate and reveal. but I failed at that for texturing lol. I think I could brute force it with geometry to replicate it but that just seems wrong. Also I keep running into Lights inside Volumes on my projects.. makes clearing up noise pretty miserable! Will return to this project after school and expand on it.
  20. Frozen Volume using Upres node

    Came across this effect by accident...just tweaking the Upres node. Am wondering how you masters would go about doing this? Cheers!
  21. Hi, I just want to do it for experimentation. What's the best way to break up the edges of a pyro sim post sim with or without rest fields, and avoid swimming noise? If I have dual rest fields, do you combine them using a Mix node where the connections are rest, rest2 fields and rest2_ratio as the bias? Because there is also rest_ratio attribute. After this, do you displace the density volume using velocity field, gradient of the density or gradient of the SDF converted from density? Also negate the direction? I read here some people advising to use gradient or velocity to the position of the noise for example. Lastly which noise is more suitable for this task? Thanks a lot
  22. Hey! I'm looking into rendering some clouds with arnold, but as far as I understood I can only render cached vdb files, problem is this workflow looks very slow as I have to go back and forth between volume shaping and rendering, and if I have to write out vdbs each time I change something I'm not sure this will be ideal for me! cheers!
  23. Hello, I have a problem with a FLIP fluid scene. I fill a sphere and move it down and upwards. After this movement, I have the same amount of particles but not the same volume… By the way, are there any good practice collections for flip fluid? I'm still struggling with it. flip.hiplc
  24. VDB RENDERING ARNOLD

    Hey ! So I made a particle simulation in houdini, from a base mesh then I convert the particles to VDB and then back to polygon with the the convertVDB node. I exported a frame in OBJ en opened in Maya, next to my original base mesh. I apply the same arnold volume texture to both, and I got 2 totally different looks. How is this possible ? They are both polygons ? (The one in T-pose is the original base mesh).
  25. Heightfield Isolines?

    I'm meddling with Heightfields and one thing that seems to be missing int the workflow and amazed me in 3DSMax Forest plugin is the convert masks to curves. Is there a way to create isolines in Houdini from either @height or @mask? I'm looking into creating road/river/track networks into terrain so if there's any good reference to follow let me know, thanks. For now I'm just generating them irrespective of the heightfield.
×