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Everything posted by rbowden

  1. If this is just smoke and you are using the fluid source and source volume DOP, just name your densities something different (densityCold and densityWarm for example). Do your simulation and then use 2 DOP I/O nodes to bring in each density separate. From there you should be able to write out the VDBs separate like you want.
  2. Strange Bullet Solver Motion

    That definitely looks suspect. Can you upload the file or even a simplified version with the problem?
  3. Ocean sim help

    If using the shelf tools (which I assume you are), I would change the size value of the particle fluid tank. If you do that, you are lowering the upper bounds of your domain also which means that you will have to do more readjusting. I would instead raise the center Y value if you want to make the fluid thinner. If you do it like this, the domain size will remain the same.
  4. @art3mis If you are doing a SOP based approach, what is stopping you from using the Boolean SOP to make cuts? You can use proxy geo for your simulation and then replace the proxy geo with your high res geo post sim. Unless you are specifically tied to voronoi for some reason?
  5. Flip and Divergence.

    Using divergence in a sim is pretty straightforward. You can add a divergence attribute in a wrangle in sops or use a gas field wrangle in dops to do so. The only gotcha is that you have to enable divergence on the FLIP object (under the initial data tab). I am attaching a basic file that use a gas field wrangle dop with some notes that should help. divergence.hip
  6. Collision Geometry for Ocean Waves Simulation

    The reason why your vdb isn't looking right is because of the way your ship was modeled. It is not a water tight mesh which, is what you need to get a solid vdb. The model has a bunch of intersections and overlapping polygons in it and is probably making the PolyFill SOP confused. If you are just doing this for practice, I would find another ship to download and use that instead. You will have plenty of time to fix other dept mistakes in your career. If this is for a paid project though, you are going to have to spend the time cleaning this mesh up.
  7. sandstorm not rendering

    Its because your dop IO in your pyro_import is still pointing towards /obj/Dust_Simulation/pyro1 instead of /obj/Dust_Simulation/pyro This is why having multiple pyro setups in one dopnet can be bad idea. Things can start getting confusing pretty quick.
  8. Flip fluid stick on collision

    Do you have Stick on Collision turned on in the fluid solver? Its located under Volume Motion---Collisions Once you turn that on, it should open up some options for you to control the sticking a bit more.
  9. FLIPs Waterline Feature

    I am trying to understand what you are going for here. You are keying the waterline parameter up so the water level will raise higher and lower? Maybe posting a sample file of what you are experiencing would help more in this case.
  10. RBD's slowly sinking into yoghurt Flip Sim

    Feedback scale is a tricky parameter to get right. You change one thing with the object you are trying to float (density, scale, etc.) it is going to screw that number up. Alot of times you can get away with a value of 1-5 but, I have had to do it in a scale of 100 before. I couldn't get it working in the file you posted for some reason and if I can't get it working in the first ten minutes, I just remake the scene. That is exactly what I did and feedback scale is working like it should. I will leave it up to you to figure out the sinking part...Off the top of my head though, I would probably time a velocity field that pushes down at a certain time and randomize it per packed object you have. Attached is a working feedback scale file. Swirl_03_RB.hip
  11. Noise in Flip fluids

    I would add some jitter to your inital flip points. That should get rid of the banding. I am attaching a file with the changes. You will still need to mess with the smoothing and such in the particle fluid surface to make the surface not as flickery but, it gives you a starting place. You are also going to have a grand time dealing with UVs if you plan on transferring them to the particle fluid surface (which it looks like you want to....Take a look at the uvquickproject node to see why). I'm curious on why time stretching would get rid of banding artifacts like this? MyHead_v07_RB.hipnc
  12. Smoke Collision Voxels

    Could be a couple of things happening but, hard to pinpoint without having a hip file to debug. Can you post your file or recreate a simple example with this happening?
  13. Issues with VDB as RBD Collision Object

    If you want to use RBDs, you need to change the drop down on the rigid body solver from bullet to RBD. Since it is set to bullet, it is creating a convex hull across to connect each box.
  14. Flip Sim and Flat Tank don't collide with each other

    I am a little confused. To make sure I have this right, you already did a water explosion and now you want to take that result and have that collide with another tank? Or did you make the water explosion in just a popnet (non flip)? Basically are you creating something like this? https://vimeo.com/106930270 Or are you trying to emit flip particles from an actual mesh?
  15. Melting effect

    Don't have the bunny geo so, can't really add to your file because it is erroring out. If you want to do this as a flip sim, I would look into doing some variable viscosity. Here are some forum posts to put you in the right direction: https://www.sidefx.com/forum/topic/31114/ https://www.sidefx.com/forum/topic/31574/ http://forums.odforce.net/topic/21855-viscosity-by-attribute-how/ http://forums.odforce.net/topic/23904-melting-flip/ Also in the help, you have an example for variable viscosity. Since these are particles you are dealing with, you could try and get some tendrils using POP nodes and plug them into the particle velocity input of your flip solver (2nd input).
  16. peaks in flip tank

    That is a pretty low res fluid you are trying to mesh. If you are just doing this as just a test, run your simulation out at a particle separation of something like .05 (should give you about 680k particles) and then set your particle fluid surface separation to be the same value. That will already help out alot...If you still want more sharper peaks, put a peak SOP after your particle fluid surface and put it at a value of something like -.06.
  17. Pump not working

    So you have a file SOP in your file that is used to bring in your cannon geometry. You didn't upload the cannon geo with your file so when someone else downloads and opens your file, the whole network doesn't work because it is missing that geometry. To get around that, you need to lock your file SOP so that the geometry gets saved inside your file. To lock your file SOP, you need to click the lock flag on the node. It is right beside your bypass flag...click that and re-upload if you are still having issues with the pump.
  18. Isolating active pieces in RBD sim

    Here is a simple setup that deletes the points based on the active attribute. isolate_active_RB.hip
  19. Pump not working

    Was the pump working before the crash? Hard to debug exactly what is going on in your file since you didn't lock your cannon file node before uploading the scene.
  20. I am confused on what exactly is the problem here? From looking at your file, the vdb reshape is working correctly and it is grouping the points inside the pig. I assume that is what you want because that is what the grains masterclass is doing with this (which you are creating this from). Using Houdini 16.0.542
  21. Should just be Xform Time Samples yeah? Render Properties -- Rendering -- Xform Time Samples.
  22. Lock you ship geo and your surface geo and then upload the file. If you do that, you won't have to worry about uploading everything. The geo will get saved in your hip file on the frame you locked it on.
  23. You have multiple people in this thread trying to help you but, you keep responding with that doesn't work. Show us what your material network looks like. Post up your rendered results so far. Put up a .hip file of what you have so far. That part in your OP you have circled is just a velocity (aeration) pass.The thread that @Federico posted should help you with that and it even has hip files in there for you. Have you checked them out? Have you tried to implement what is in those threads in your own file yet? If so and it still isn't working, show us what isn't working for you.
  24. The term you are looking for is flowmap and you don't necessarily need to do a sim to create one. You can do a complete sops based approach to do it but, you can do a flip sim to create one though if you really need to: https://github.com/sideeffects/GameDevelopmentToolset Has an example of how to do that but, I have a feeling it will become alot easier with H16.