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Farmfield last won the day on December 7

Farmfield had the most liked content!

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About Farmfield

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    Houdini Master
  • Birthday 04/14/1971

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    Johnny Farmfield
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  1. Particles along surface

    Oh, ok, I think I understand the perceived problem, and then I'm with Matt, it's really nice to be able to set that up on a static object and then apply the animation on tip - of course depends on what you want to do....
  2. Particles along surface

    LOL; what? The minpos works just fine on an animated object... animated_minpos.hiplc
  3. sticky slime

    There are several tricks you can use for the sticking, like forcing it by raying the closest particles to it, but the stringiness I suspect you are looking for might be tricky to get without diving a bit deeper into the solver crap and play with stuff like gas elasticity - though you might be able to tweak it into existence balancing surface tension and viscosity, or at least that's what my instincts are telling me, hehe...

    Ran into this thread by accident now but yeah, the grain solver works great for doing packing - random points, increase pscale per frame until it collides with something and beyond that it's just making sure it doesn't birth new seed points inside current spheres. In this case I just locked the setup to a surface and used intersection analysis and the polypath to create the circles, but if you birth the points in a volume you have sphere packing and if you want to use more complex objects, you just set this up with the bullet solver.
  5. Differential curve growth

    Hmm, there's a slight weirdness going on in those clips so when I get time I'll put on a face mask, some rubber gloves, and investigate the mysteries of this organic compound.
  6. Animating along curves with UVs are one way, and the example files on cg-wiki are amazing, but I also love the sort shift point number thingie I've used in many setups, hehe - and I know it's stupid, but I just love it.
  7. Yeah, there's no need to go for POPs - and it all depends on what type of effect, how much control you want/need, etc... Here's a non simulated setup using find shortest path SOP.
  8. There is no deception used here, it's just quite simple, hehe... It's just a habit, rather than scattering a single point on a surface, I usually just use one off the surface, so a sort randomly and then delete everything except point 0. Here I sort by Y and then delete everything but the lowest one. So the bottom most point is there and I feed that into the POP. The convert line SOP converts every primitive to lines between it's connecting points. If I didn't delete the surface, the minpos function would ray the point to the surface, but here I just want the structure of the mesh for the particles to follow. And I didn't need the restlength, but I just didn't bother about unchecking it, doesn't have any influence at any point here accept eating a small amount of memory. And yes, the minpos function moves the point to the closest surface position of the target, in this case input two where I piped in the line structure of the half sphere. And finally the wrangle where I normalize velocity and multiply it by 0.1 to force a constant velocity of the particle - else its speed would be controlled by the noise function of the POP wind, with wouldn't be very fitting for particles representing some kind of information flow or alike. If you want different speeds for each particle, you could use something like multiplying the velocity with rand(@id).
  9. You could use a substructure for the possible routes for them to take, then you can have them behave half "free" and half controlled, so to speak. pop_ray_to_line.hiplc
  10. Resample curve by width/pscale

    Funny enough, this was again asked in the Houdini Artists Facebook group and I had completely forgot about asking this back in April... Either way, here's two other SOP based solutions to this problem, the second one a bit of a joke, of course - though I have no doubt that method can be useful for some things as well... v1: https://drive.google.com/open?id=1mjJd0vd9KUSFW79ksRc5fioeMxXnu6Bu v2: https://drive.google.com/open?id=1mjJd0vd9KUSFW79ksRc5fioeMxXnu6Bu
  11. Differential curve growth

    Just wanted to post this as an example of using this technique as foundation for something else. Scene file in the Vimeo description.
  12. N-body via SOP solver with OpenCL

    Upped both scatters to 100k points and it still sim'ed 300 frames in about 2 minutes - just crazy. Very cool.
  13. Bullet: Activate on Collisions or Start Sleeping

    I have no clue what this was about, though - that was 13 months ago, I gotta download and check the file.
  14. Create multiple FEM over time?

    I was so close doing a wrangle when I remembered - there's wheels already, no need to reinvent one.
  15. Create multiple FEM over time?

    With a copy stamp, random vector per point (per frame) would solve it.