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Everything posted by timfagan

  1. Is there a way to visualize and access the local forces in a solid/FEM object? There doesn't seem to be any attributes of force / stress / strain, or even kinetic energy with the energy attributes turned on in the fem solver (the Sidefx masterclass in FEM had a bouncing ball colored by the kinetic energy). The object in the DOP network only has the visualization tab for thickness, penetration, velocity and UVW.
  2. ocean spectrum questions

    Have you tried using the 'Filter Above Resolution' on the ocean spectrum node? You can clear away those higher frequency waves by setting a lower value.
  3. Fracturing Wood Panels - work flow

    So I've been trying to figure out how to fracture panels of wood! I've got a method here but I'm hoping there's a better approach. I wanted a high strength/glue value within each panel piece and close to zero between panels. The basic idea is to pass an attribute which has a unique value for each panel and use this to create the clusters. Then delete the glue links between different clusters. It works but I'm kinda hoping someone has a better approach, as this one gets quite slow especially moving around in DOPS. See an example of the final glue network attached. Anyway I've set up the file so there's very few fractures so it loads quickly, but to really get it to work it needs at least around 3000 points. So if you check out the file have a look at it, then increase the number of of points on the scatter node. One problem is that I haven't been able to get the nice elongated 'wood' fractures via the transform before/after method - it changes the glue network taken from the voronoi fracture node.... Also, the cluster tab on the voronoi fracture node seems to have no effect? If this worked all this would probably be unnecessary. Wood_Panel_Fracture.hipnc
  4. Fracturing Wood Panels - work flow

    I can't see looking at it what's wrong, but I like how you used the foreach on the plank pieces to create the voronoi fracture. Saves the extra attribute trying to separate the wood pieces later...
  5. I can't seem to add an image with the 'upload from file' option using the photo editor. I've tried jpeg, png and gif with chrome and firefox. Any suggestions?
  6. Fracturing Wood Panels - work flow

    Thanks Johnny, yeah the only problem with using those transforms is that it effects the glue network extracted from the voronoi fracture node, it's all shrunk down. Maybe there's a way to compute this separately though. Or just scale that network back up, I'll check this when I'm in front of it later.
  7. Lava flow

    Really cool, maybe some light/shadow projected from the lava to the environment and the steam doesn't seem to follow the lava as it pours down.
  8. Can't add image with photo editor

    I ended up just loading an image on to a free image hosting service and linking with the URL.
  9. I'm wondering if anyone has figured out how to solve this problem with the extrude sop? I have a trace of the letter C, and I would like to add an inset with the extrusion. However the result has overlapping polygons. Is there a way to correct this? I thought it might be to do with the normals but they're all in the same direction... Edit: What I'm trying to get is the extrusion meeting in the middle of the letter....
  10. Inset with PolyExtrude - overlapping polygons

    Thanks guys, yeah I found the polyexpand2D to be pretty useful as it avoids the overlapping when extruding in a flat plane.
  11. Inset with PolyExtrude - overlapping polygons

    If I wanted to smooth that middle line/edge, can I resample just that line somehow? I've managed to isolate the line through either a group SOP, but can't seem to resample it. Or I can delete everything except those middle line points and resample them, but I'm not sure how to reinsert them back to the mesh... (The resample node has that option to treat polygons as Interpolating Curves, which smooths out the line as it inserts points.) I've fiddled around with the connect adjacent pieces and using that to try to form a polygon mesh. I also tried converting them to NURBS curves, and skinning them together, but they don't connect correctly. C_smooth.hipnc
  12. Inset with PolyExtrude - overlapping polygons

    Haha that's really cool, I haven't seen those sops used in that way before. thanks again.
  13. Inset with PolyExtrude - overlapping polygons

    Also with the polyextrude, what you say makes sense, but anytime an inset is applied with a high angle between adjacent edges, it seems there's going to be overlapping polygons, as in the ends of the 'c' above. Is that right? I'm sure there's a way to correct for it, I don't know what it is right now...
  14. Inset with PolyExtrude - overlapping polygons

    Yeah looks spot on, thanks for the tip Konstantin.
  15. Inset with PolyExtrude - overlapping polygons

    ...A resample node before the extrusion cleans it up a bit. I'm still not sure how to clean up the edges.
  16. Displacement in Mantra

    Hey guys, I'm relying on displacement to create procedural paneling and I'm having some issues. When making panels, would it be a wiser approach to build it procedurally at object level rather than rely on the shader? In the checkerboard pattern, light gets through between the positive and negative displacements. Is there a way to fix this in mantra? Also there's no back face... In the other image, the white area should all be displaced the same amount, but some sections seem just translated out.
  17. Hey Atom, yeah it seems they need to be primitive attributes. This might help: https://www.sidefx.com/index.php?option=com_forum&Itemid=172&page=viewtopic&t=38882&highlight=stylesheets
  18. Can't add image with photo editor

    It's in my profile settings. It recognizes the file, the name is there, but it doesn't actually load as a preview or a crop'able image. The done button also doesn't make it appear as the profile image... There's no errors. I feel like I must be doing something stoopid because everyone else has one.
  19. I'm trying to use a flip sim field to effect a pyro sim field (fuel). I want to use the FLIP particles to locally remove the fuel for the pyro sim. In SOP level this would be straightforward with an attribute transfer node, but in DOPs it's not quite clear to me yet. I'm using an Apply Data and Fetch Data to get a field from the FLIP sim, which at the moment is just the viscosity (because it is a scalar = 0). And then a Gas Calculate to transfer it to the fuel field on the pyro sim. Unfortunately it seems to just replace the whole field rather than just where the particles are close to the fuel source. I guess I just need a way to make the transfer local to the particles. I tried adding "Geometry" to the Source Index on the Gas Calculate node, hoping it would be able to use the FLIP particles as reference points for transfer, but this didn't work. I have a test scene attached. Just switch the Gas Calculate on... testing_01.hipnc
  20. best way to locally transfer FLIP field to Pyro Field

    Great thanks ranxerox! I didn't realize the operation (like minimum etc) on the gas calculate was upon the whole volume, so that helps a lot. On that note, do you (or anyone) understand how the data is transferred between fields in DOPs? For example: I have a system here transferring a scalar field from a pops network to a scalar field on a pyro network. The particles slowly rise up into the pyro field. See the attached images for what happens. The particle region is much smaller than the pyro field. Where the regions overlap the transfer is fine, but outside here the values are extrapolated right across the whole pyro field. I'm using a simple vopsop to directly pass the data which could be causing a problem. One tricky thing is that the fetch data node cannot be visualized, and can't be added to another field - so I've created a field and passed the data onto it. The scene file is attached. ignite_fuel_particles_01.hipnc
  21. transform node

    I'm trying to simply move a polygon sphere around in my scene, attaching a transform node usually lets me use the move tool (T) to move the whole thing around. But for some reason when I click my sphere it is auto attaching an edit node to my node tree and making me select individual polygon faces to move. I think I must have miss clicked some setting or something, because it hasn't done this before and I can't seem to get it back.... Is there a way to stop this annoying auto-behavior? thanks in advance!
  22. Weird FLIP collisions

    I'm not sure if this is what you're after, but you can adjust the forces on the fluid to change the look: In the flip solver, there's a collisions tab, and you can adjust the force scale. This will scale up or down any forces acting on the fluid, so you can create more splash for example. I think this was a force scale of 8 or 10 (and increased resolution). You can also adjust the feedback scale on the solver tab so that forces from the fluid effect other bodies. The box I used here is a rigid body falling under gravity, so to make the box float, you can just increase the force scale as it's default to zero.
  23. jitter in solid sim

    I'm using the solid FEM solver and I'm getting a weird jittering once the object has come to rest on the ground plane. Is there any way to remove this? I've increased the substepping but it doesn't seem to help, neither deleting poor quality primitives. I've seen other videos where these seems to happen, but there must be a way to get rid of it?
  24. Cloth Pulling wires

    I've just started looking at a similar problem so I had a go at your sim. I think the green constraint spheres jumping around in the sim are a good indication that it needs some sub-stepping. Also there wasn't any damping on the wire, which helps remove excess energy and jerking around. I managed to get a working version by: - increasing the substeps on the wiresolver - adjusting the parameters for the wire object (physical and elastic properties) - moving the wind force to the cloth object only (found in the drag tab). Not a huge amount of movement on the flag but you could probably fiddle with the wind force and the properties of the cloth to get more variation. Wiresolver_2.hipnc
  25. You need to change the box object from active to static in the initial object type selector. Also helping you would be easier if you could take an extra moment to write a bit more clearly.