thanaras Posted July 25, 2009 Share Posted July 25, 2009 Hello, I was wondering if you can add viscosity and/or elasticity to POPs. Is there anyway to get this forces applied to particles without going to DOPs? Thanks a lot in advance. Quote Link to comment Share on other sites More sharing options...
nanocell Posted July 25, 2009 Share Posted July 25, 2009 The answer is both no and yes. As far as I know there is no tool included in the stock Houdini to allow you to do this. But I'm sure it's possible to develop a viscoelastic particle fluid solver as a POP node, if you've got a programmer willing to do so . So the answer is probably more no than yes. CheerZ, Van Aarde. Quote Link to comment Share on other sites More sharing options...
SpencerL Posted July 25, 2009 Share Posted July 25, 2009 The answer is both no and yes. As far as I know there is no tool included in the stock Houdini to allow you to do this. But I'm sure it's possible to develop a viscoelastic particle fluid solver as a POP node, if you've got a programmer willing to do so . So the answer is probably more no than yes. CheerZ, Van Aarde. The nice thing about Houdini, is you can actually create what you need without the use of programing/scripting. Depending on what you are trying to achieve, you can get nice results using either the attribute transfer POP > Smooth Particle Sampling or if you are familiar with point clouds, you could create a VOP POP and feed seed points with velocity and use those seed points to drive your particle systems velocity/accel. At some point, ill try to knock together a basic example. Quote Link to comment Share on other sites More sharing options...
thanaras Posted July 26, 2009 Author Share Posted July 26, 2009 Is there any other way to "fake" viscosity in POPs? Quote Link to comment Share on other sites More sharing options...
pclaes Posted July 27, 2009 Share Posted July 27, 2009 This file will simulate the viscosity through the interact pop and drag pop. I could not get a smoothing of the velocities to work because I think I read somewhere that pointclouds in pops do not work (perhaps this was one of the reasons why those flocking systems in pops don't seem to work in vops.). Also did that sdf collision vop pop so the particles slide over a collision object. The avi is an .mp4 particles_viscosity_04.hipnc viscosity_02.avi Quote Link to comment Share on other sites More sharing options...
SpencerL Posted July 27, 2009 Share Posted July 27, 2009 (edited) This file will simulate the viscosity through the interact pop and drag pop. I could not get a smoothing of the velocities to work because I think I read somewhere that pointclouds in pops do not work (perhaps this was one of the reasons why those flocking systems in pops don't seem to work in vops.). Also did that sdf collision vop pop so the particles slide over a collision object. The avi is an .mp4 Point Clouds actually do work in pops. Here is a simple example. popPointCloud_001sl.hip Edited July 27, 2009 by SpencerL 1 Quote Link to comment Share on other sites More sharing options...
pclaes Posted July 27, 2009 Share Posted July 27, 2009 hmm, yes I see what you did. So I guess as long as you are not referencing the point cloud "file" from within the same POP context it is fine? Or is it because you are really referencing the point cloud "file" from a SOP path? In the file I posted I have a little vop pop trying to reference a point cloud from the already existing particles (and average the v). Perhaps there is a possibility to cache the particles or use a timeshift in SOPS to be able to sample the pointcloud from the previous frame from SOPS inside of POPS. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.