tagosaku

Hi, I have a question about how oceanEvaluatenode in SOP, and ocean_samplelayers node in VOP/MAT pick and match up each spectrum and mask. For instance, I start from shell, ocean flat tank. And go to obj>flattank_fluid_extended. There are node network to create a bake_spectra and bake_masks cache file. They split , cache and merged them, and feed to oceanValuate. From there, I delete hifrequency_mask node and created 1 more oceanSpectrums and 1 more custom mask. After that, I don't know how to make a coupling/group of default spectrum & default mask, and sceond spectrum & customMask, before merging all spectrums and masks to output. There are primitive names, phase, frequency, amplitude, pointmask, mask in geometry spreadsheet. I guess they check primitive number or some group attribute to make each displacement group?? Also, what pointmask does do? Thanks!!

Hi, I try to make my default set up. Then I want to make a auto-enable setting for staticObject node, instead of creating/deleting the node every time. This is because whitewater solver, for instance, makes a strange collision artifact if staticObject node does not get any collision objects from SOP. So far, I tried a enableSolver, switch node with if(nprims(surface)>0, 0, 1), etc. None of them works well. Alternatively I made to insert a dummy object in SOP, then the staticObject takes it to avoid artifact. We could unlock the staticObject node and implement nodes in there, but I want to avoid this way because it causes a file size larger. Does anyone have smart ideas to do auto-enable/bypass staticObject node?

Hi, The picture shows an object , create > test geo > add velocity > vdbFromPolygon with vel field > visualize velocity. I wonder how to split velocity to tangent velocity and normal velocity. I guess we don't have a node to do it by one click, and need to work on volume vop/wrangle. If anyone knows how to do it, I will appreciate it, thanks!

Thank you, Bunker, for your tips. 1 - It sounds that we don't have so much chance to use pump and sink node operations. 3 - I will use droplet feature to just detect it, and use wrangle to control droplet externally. And, I am still wondering theoretical aspect like a my #1 question. Houdini'd FLIP is designed to modify the both of particles and field together, or just modify one of them.

Hi, I have general questions about FLIP. For instance, there are splashes like an attached picture. If I want to change velocity or delete splash/spray, I think there are 3ways. The FLIP concept could make it tricky because FLIP contains particle and volume fields together. Thus, questions are: 1 - in general, if I want to change velocity or delete splash, do I need to modify the both of particles and field together? Or just modify one of them? 2 - It's kind of similar question as #1, but, when we use sinkFLIP and pump and sourceFLIP; 2a - pump seems to add velocity, but it's strange why source volume sets copy, and velocity sets normalized?? It should set source Volume none, and set velocity normalize OFF. Also, why don't we use pop node to change particle velocity directly?? 2b - sink seems to just kill particle, but why sourceVolume is maximum? It should be subtract although it's not exist.. And there is still surface volume exists after deleting particle... Can't we use just pop kill to remove waterVolume/splash? 3c - sourceFLIP looks just adding particle. I guess we can add velocity with particle together, then when it passes solver, it create water volume (surface field and vel field), then why don't we just use pop-source to add particle with velocity?? 3 - There is FLIP solver > particle motion > Droplets > and min/max particle Density. However, there is no density attribute. What density talks about and how they calculate density?? Thanks for reading a lot of questions!!

vtrvtr, thank you so much for your reply. I tried your instruction, and my understanding is that it's required to : 1 HDA , not subnet 2 only SOP level I could wish to use it for a SOP subnet, but not avaliable. Anyway, that's good to know where this guide-geo from!

hi, I have a question about this display function: white water source > visualization > show surface Then blue object shows up. I know this object represent VDB, but I wonder how this tool creates the visualization. I dig into >edit parameter interface, but cannot find any particular trick. At least I found a reference null node inside of the tool. Does anyone know how to create this visualization?

Hi, LaidlawFX Thanks for your reply. I will write RFE to sidefx, thanks

Hi, I was reading this thread; I checked file "vol_curv.hipnc" and that's great, and I wonder if we can always output a normalized range mostly -1 to 1, probably using voxel size info . I know it could be depends on polygon object and value could not reach max1 or min-1 all the time, but would not exceed -1 ot +1. For instance, it sets vdbfrompolygons1>voxel 0.2, and vdb analysis' curvature shows the range -1 to 10. When it sets voxel size to 0.1, curvature range become -3 to 14, etc. I know, after calculating curvature, we can normalize it by a fit node. But it would be great to output normalized curvature approximately -1 to 1 in all the time, regardless voxel size. Thanks

I recently checked file "vol_curv.hipnc" and that's great, and I wonder if we can always output a normalized value. It would be a range mostly -1 to 1, probably using voxel size info . I know it could be depends on polygon object and value could not reach max1 ot min-1 value. Right now, for instance, it sets vdbfrompolygons1>voxel 0.2, and curvature range -1 to 10. When it sets voxel size to 0.1, curvature range become -3 to 14, etc. I know, after calculating curvature, we can normalize it by fit node. But it would be great to output normalized curvature approximatly -1 to 1 in all the time, regardless voxel size. Thanks

David, thank you for the detail information and I also learned how to use principlecore node, instead of principle shader.

I guess you made those nodes and principleCORE in a material builder. In stead of your idea, I was trying to say to combine/mix existing shaders and AOVs under matnet level. Probably my logic won't work..

Yeah, I already tweaked a static threshold and scale kinetic. These parameters reduce particle's expansion and push-away. However, it causes more #3's problem, springy and rebounce motion. #2 and #3 problems conflict each other to fix the both.

hi, I try to make snow effect with grain solver, started from wet sand shell, wetness=1, and changed clump stiffness to 100. After tweaking around parameters, I got 3 main problems. 1 – how to add friction to static object? I set friction 10, bounce 0 , but particle is still sliding a lot. 2 – When dynamic object collide grain particle, it pushes away too much, but should not influence to surrounding particles. I think constrain pushes away in order to keep space between particles. 3 – particle motion is kind of springy or bouncy. Snow should damp velocity immediately. I guess I need to figure out how to control compression or density of particles by grain's internal constraint?! If anyone knows solutions, it would be great, thanks! grainSnow_v01.hip

David, >>creating your nodes inside materialbuilder VOP for convenient aov workflow. Yes, that's what I plan to do. >>second - I think you never have to unlock the shader to build aovs (at least I've never had to). No. Create, for instance, principledshader, or pyroshader. It's locked. Then I wish to create AOVs not-inside of these shaders.